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1.
Nature ; 575(7784): 652-657, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31748747

RESUMO

Mosaic loss of chromosome Y (LOY) in circulating white blood cells is the most common form of clonal mosaicism1-5, yet our knowledge of the causes and consequences of this is limited. Here, using a computational approach, we estimate that 20% of the male population represented in the UK Biobank study (n = 205,011) has detectable LOY. We identify 156 autosomal genetic determinants of LOY, which we replicate in 757,114 men of European and Japanese ancestry. These loci highlight genes that are involved in cell-cycle regulation and cancer susceptibility, as well as somatic drivers of tumour growth and targets of cancer therapy. We demonstrate that genetic susceptibility to LOY is associated with non-haematological effects on health in both men and women, which supports the hypothesis that clonal haematopoiesis is a biomarker of genomic instability in other tissues. Single-cell RNA sequencing identifies dysregulated expression of autosomal genes in leukocytes with LOY and provides insights into why clonal expansion of these cells may occur. Collectively, these data highlight the value of studying clonal mosaicism to uncover fundamental mechanisms that underlie cancer and other ageing-related diseases.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Y/genética , Predisposição Genética para Doença/genética , Instabilidade Genômica/genética , Leucócitos/patologia , Mosaicismo , Adulto , Idoso , Biologia Computacional , Bases de Dados Genéticas , Feminino , Marcadores Genéticos/genética , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/genética , Reino Unido
2.
PLoS Genet ; 18(1): e1009887, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35061662

RESUMO

Morning-preference chronotype has been found to be protective against breast and prostate cancer. Sex hormones have been implicated in relation to chronotype and the development of both cancers. This study aimed to assess whether sex hormones confound or mediate the effect of chronotype on breast and prostate cancer using a Mendelian Randomization (MR) framework. Genetic variants associated with chronotype and sex hormones (total testosterone, bioavailable testosterone, sex hormone binding globulin, and oestradiol) (p<5×10-8) were obtained from published genome-wide association studies (n≤244,207 females and n≤205,527 males). These variants were used to investigate causal relationships with breast (nCases/nControls = 133,384/113,789) and prostate (nCases/nControls = 79,148/61,106) cancer using univariable, bidirectional and multivariable MR. In females, we found evidence for: I) Reduced risk of breast cancer per category increase in morning-preference (OR = 0.93, 95% CI:0. 88, 1.00); II) Increased risk of breast cancer per SD increase in bioavailable testosterone (OR = 1.10, 95% CI: 1.01, 1.19) and total testosterone (OR = 1.15, 95% CI:1.07, 1.23); III) Bidirectional effects between morning-preference and both bioavailable and total testosterone (e.g. mean SD difference in bioavailable testosterone = -0.08, 95% CI:-0.12, -0.05 per category increase in morning-preference vs difference in morning-preference category = -0.04, 95% CI: -0.08, 0.00 per SD increase in bioavailable testosterone). In males, we found evidence for: I) Reduced risk of prostate cancer per category increase in morning-preference (OR = 0.90, 95% CI: 0.83, 0.97) and II) Increased risk of prostate cancer per SD increase in bioavailable testosterone (OR = 1.22, 95% CI: 1.08, 1.37). No bidirectional effects were found between morning-preference and testosterone in males. While testosterone levels were causally implicated with both chronotype and cancer, there was inconsistent evidence for testosterone as a mediator of the relationship. The protective effect of morning-preference on both breast and prostate cancer is clinically interesting, although it may be difficult to effectively modify chronotype. Further studies are needed to investigate other potentially modifiable intermediates.


Assuntos
Neoplasias da Mama/genética , Hormônios Esteroides Gonadais/metabolismo , Análise da Randomização Mendeliana/métodos , Polimorfismo de Nucleotídeo Único , Neoplasias da Próstata/genética , Fenômenos Cronobiológicos , Bases de Dados Genéticas , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Masculino , Fatores de Risco
3.
Am J Hum Genet ; 107(2): 325-329, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32574563

RESUMO

Large copy-number variants (CNVs) are strongly associated with both developmental delay and cancer, but the type of disease depends strongly on when and where the mutation occurred, i.e., germline versus somatic. We used microarray data from UK Biobank to investigate the prevalence and penetrance of large autosomal CNVs and chromosomal aneuploidies using a standard CNV detection algorithm not designed for detecting mosaic variants. We found 160 individuals that carry >10 Mb copy number changes, including 56 with whole chromosome aneuploidies. Nineteen (12%) individuals had a diagnosis of Down syndrome or other developmental disorder, while 84 (52.5%) individuals had a diagnosis of hematological malignancies or chronic myeloproliferative disorders. Notably, there was no evidence of mosaicism in the blood for many of these large CNVs, so they could easily be mistaken for germline alleles even when caused by somatic mutations. We therefore suggest that somatic mutations associated with blood cancers may result in false estimates of rare variant penetrance from population biobanks.


Assuntos
Variações do Número de Cópias de DNA/genética , Hematopoese/genética , Adulto , Idoso , Alelos , Aneuploidia , Bancos de Espécimes Biológicos , Cromossomos/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mosaicismo , Mutação/genética , Penetrância , Reino Unido
4.
Am J Hum Genet ; 104(1): 157-163, 2019 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-30583798

RESUMO

Erectile dysfunction (ED) is a common condition affecting more than 20% of men over 60 years, yet little is known about its genetic architecture. We performed a genome-wide association study of ED in 6,175 case subjects among 223,805 European men and identified one locus at 6q16.3 (lead variant rs57989773, OR 1.20 per C-allele; p = 5.71 × 10-14), located between MCHR2 and SIM1. In silico analysis suggests SIM1 to confer ED risk through hypothalamic dysregulation. Mendelian randomization provides evidence that genetic risk of type 2 diabetes mellitus is a cause of ED (OR 1.11 per 1-log unit higher risk of type 2 diabetes). These findings provide insights into the biological underpinnings and the causes of ED and may help prioritize the development of future therapies for this common disorder.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Disfunção Erétil/etiologia , Disfunção Erétil/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Hipotálamo/patologia , Alelos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Cromossomos Humanos Par 6/genética , Simulação por Computador , Europa (Continente) , Humanos , Masculino , Proteínas Repressoras/genética
5.
Genet Med ; 24(9): 1909-1919, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35687092

RESUMO

PURPOSE: The study aimed to systematically ascertain male sex chromosome abnormalities, 47,XXY (Klinefelter syndrome [KS]) and 47,XYY, and characterize their risks of adverse health outcomes. METHODS: We analyzed genotyping array or exome sequence data in 207,067 men of European ancestry aged 40 to 70 years from the UK Biobank and related these to extensive routine health record data. RESULTS: Only 49 of 213 (23%) of men whom we identified with KS and only 1 of 143 (0.7%) with 47,XYY had a diagnosis of abnormal karyotype on their medical records or self-report. We observed expected associations for KS with reproductive dysfunction (late puberty: risk ratio [RR] = 2.7; childlessness: RR = 4.2; testosterone concentration: RR = -3.8 nmol/L, all P < 2 × 10-8), whereas XYY men appeared to have normal reproductive function. Despite this difference, we identified several higher disease risks shared across both KS and 47,XYY, including type 2 diabetes (RR = 3.0 and 2.6, respectively), venous thrombosis (RR = 6.4 and 7.4, respectively), pulmonary embolism (RR = 3.3 and 3.7, respectively), and chronic obstructive pulmonary disease (RR = 4.4 and 4.6, respectively) (all P < 7 × 10-6). CONCLUSION: KS and 47,XYY were mostly unrecognized but conferred substantially higher risks for metabolic, vascular, and respiratory diseases, which were only partially explained by higher levels of body mass index, deprivation, and smoking.


Assuntos
Diabetes Mellitus Tipo 2 , Síndrome de Klinefelter , Bancos de Espécimes Biológicos , Humanos , Síndrome de Klinefelter/diagnóstico , Síndrome de Klinefelter/epidemiologia , Síndrome de Klinefelter/genética , Masculino , Aberrações dos Cromossomos Sexuais , Reino Unido/epidemiologia , Cariótipo XYY
6.
Hum Reprod ; 37(5): 1069-1082, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35274129

RESUMO

STUDY QUESTION: Can additional genetic variants for circulating anti-Müllerian hormone (AMH) levels be identified through a genome-wide association study (GWAS) meta-analysis including a large sample of premenopausal women? SUMMARY ANSWER: We identified four loci associated with AMH levels at P < 5 × 10-8: the previously reported MCM8 locus and three novel signals in or near AMH, TEX41 and CDCA7. WHAT IS KNOWN ALREADY: AMH is expressed by antral stage ovarian follicles in women, and variation in age-specific circulating AMH levels has been associated with disease outcomes. However, the physiological mechanisms underlying these AMH-disease associations are largely unknown. STUDY DESIGN, SIZE, DURATION: We performed a GWAS meta-analysis in which we combined summary statistics of a previous AMH GWAS with GWAS data from 3705 additional women from three different cohorts. PARTICIPANTS/MATERIALS, SETTING, METHODS: In total, we included data from 7049 premenopausal female participants of European ancestry. The median age of study participants ranged from 15.3 to 48 years across cohorts. Circulating AMH levels were measured in either serum or plasma samples using different ELISA assays. Study-specific analyses were adjusted for age at blood collection and population stratification, and summary statistics were meta-analysed using a standard error-weighted approach. Subsequently, we functionally annotated GWAS variants that reached genome-wide significance (P < 5 × 10-8). We also performed a gene-based GWAS, pathway analysis and linkage disequilibrium score regression and Mendelian randomization (MR) analyses. MAIN RESULTS AND THE ROLE OF CHANCE: We identified four loci associated with AMH levels at P < 5 × 10-8: the previously reported MCM8 locus and three novel signals in or near AMH, TEX41 and CDCA7. The strongest signal was a missense variant in the AMH gene (rs10417628). Most prioritized genes at the other three identified loci were involved in cell cycle regulation. Genetic correlation analyses indicated a strong positive correlation among single nucleotide polymorphisms for AMH levels and for age at menopause (rg = 0.82, FDR = 0.003). Exploratory two-sample MR analyses did not support causal effects of AMH on breast cancer or polycystic ovary syndrome risk, but should be interpreted with caution as they may be underpowered and the validity of genetic instruments could not be extensively explored. LARGE SCALE DATA: The full AMH GWAS summary statistics will made available after publication through the GWAS catalog (https://www.ebi.ac.uk/gwas/). LIMITATIONS, REASONS FOR CAUTION: Whilst this study doubled the sample size of the most recent GWAS, the statistical power is still relatively low. As a result, we may still lack power to identify more genetic variants for AMH and to determine causal effects of AMH on, for example, breast cancer. Also, follow-up studies are needed to investigate whether the signal for the AMH gene is caused by reduced AMH detection by certain assays instead of actual lower circulating AMH levels. WIDER IMPLICATIONS OF THE FINDINGS: Genes mapped to the MCM8, TEX41 and CDCA7 loci are involved in the cell cycle and processes such as DNA replication and apoptosis. The mechanism underlying their associations with AMH may affect the size of the ovarian follicle pool. Altogether, our results provide more insight into the biology of AMH and, accordingly, the biological processes involved in ovarian ageing. STUDY FUNDING/COMPETING INTEREST(S): Nurses' Health Study and Nurses' Health Study II were supported by research grants from the National Institutes of Health (CA172726, CA186107, CA50385, CA87969, CA49449, CA67262, CA178949). The UK Medical Research Council and Wellcome (217065/Z/19/Z) and the University of Bristol provide core support for ALSPAC. This publication is the work of the listed authors, who will serve as guarantors for the contents of this article. A comprehensive list of grants funding is available on the ALSPAC website (http://www.bristol.ac.uk/alspac/external/documents/grant-acknowledgements.pdf). Funding for the collection of genotype and phenotype data used here was provided by the British Heart Foundation (SP/07/008/24066), Wellcome (WT092830M and WT08806) and UK Medical Research Council (G1001357). M.C.B., A.L.G.S. and D.A.L. work in a unit that is funded by the University of Bristol and UK Medical Research Council (MC_UU_00011/6). M.C.B.'s contribution to this work was funded by a UK Medical Research Council Skills Development Fellowship (MR/P014054/1) and D.A.L. is a National Institute of Health Research Senior Investigator (NF-0616-10102). A.L.G.S. was supported by the study of Dynamic longitudinal exposome trajectories in cardiovascular and metabolic non-communicable diseases (H2020-SC1-2019-Single-Stage-RTD, project ID 874739). The Doetinchem Cohort Study was financially supported by the Ministry of Health, Welfare and Sports of the Netherlands. The funder had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript. Ansh Labs performed the AMH measurements for the Doetinchem Cohort Study free of charge. Ansh Labs was not involved in the data analysis, interpretation or reporting, nor was it financially involved in any aspect of the study. R.M.G.V. was funded by the Honours Track of MSc Epidemiology, University Medical Center Utrecht with a grant from the Netherlands Organization for Scientific Research (NWO) (022.005.021). The Study of Women's Health Across the Nation (SWAN) has grant support from the National Institutes of Health (NIH), DHHS, through the National Institute on Aging (NIA), the National Institute of Nursing Research (NINR) and the NIH Office of Research on Women's Health (ORWH) (U01NR004061; U01AG012505, U01AG012535, U01AG012531, U01AG012539, U01AG012546, U01AG012553, U01AG012554, U01AG012495). The SWAN Genomic Analyses and SWAN Legacy have grant support from the NIA (U01AG017719). The Generations Study was funded by Breast Cancer Now and the Institute of Cancer Research (ICR). The ICR acknowledges NHS funding to the NIHR Biomedical Research Centre. The content of this manuscript is solely the responsibility of the authors and does not necessarily represent official views of the funders. The Sister Study was funded by the Intramural Research Program of the National Institutes of Health (NIH), National Institute of Environmental Health Sciences (Z01-ES044005 to D.P.S.); the AMH assays were supported by the Avon Foundation (02-2012-065 to H.B. Nichols and D.P.S.). The breast cancer genome-wide association analyses were supported by the Government of Canada through Genome Canada and the Canadian Institutes of Health Research, the 'Ministère de l'Économie, de la Science et de l'Innovation du Québec' through Genome Québec and grant PSR-SIIRI-701, The National Institutes of Health (U19 CA148065, X01HG007492), Cancer Research UK (C1287/A10118, C1287/A16563, C1287/A10710) and The European Union (HEALTH-F2-2009-223175 and H2020 633784 and 634935). All studies and funders are listed in Michailidou et al. (Nature, 2017). F.J.M.B. has received fees and grant support from Merck Serono and Ferring BV. D.A.L. has received financial support from several national and international government and charitable funders as well as from Medtronic Ltd and Roche Diagnostics for research that is unrelated to this study. N.S. is scientific consultant for Ansh Laboratories. The other authors declare no competing interests.


Assuntos
Hormônio Antimülleriano , Neoplasias da Mama , Estudo de Associação Genômica Ampla , Hormônio Antimülleriano/sangue , Hormônio Antimülleriano/genética , Canadá , Estudos de Coortes , Feminino , Humanos , Proteínas Nucleares
7.
Hum Mol Genet ; 28(24): 4197-4207, 2019 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-31630189

RESUMO

Raised albumin-creatinine ratio (ACR) is an indicator of microvascular damage and renal disease. We aimed to identify genetic variants associated with raised ACR and study the implications of carrying multiple ACR-raising alleles with metabolic and vascular-related disease. We performed a genome-wide association study of ACR using 437 027 individuals from the UK Biobank in the discovery phase, 54 527 more than previous studies, and followed up our findings in independent studies. We identified 62 independent associations with ACR across 56 loci (P < 5 × 10-8), of which 20 were not previously reported. Pathway analyses and the identification of 20 of the 62 variants (at r2 > 0.8) coinciding with signals for at least 16 related metabolic and vascular traits, suggested multiple pathways leading to raised ACR levels. After excluding variants at the CUBN locus, known to alter ACR via effects on renal absorption, an ACR genetic risk score was associated with a higher risk of hypertension, and less strongly, type 2 diabetes and stroke. For some rare genotype combinations at the CUBN locus, most individuals had ACR levels above the microalbuminuria clinical threshold. Contrary to our hypothesis, individuals carrying more CUBN ACR-raising alleles, and above the clinical threshold, had a higher frequency of vascular disease. The CUBN allele effects on ACR were twice as strong in people with diabetes-a result robust to an optimization-algorithm approach to simulating interactions, validating previously reported gene-diabetes interactions (P ≤ 4 × 10-5). In conclusion, a variety of genetic mechanisms and traits contribute to variation in ACR.


Assuntos
Albuminúria/genética , Creatinina/metabolismo , Nefropatias/genética , Albuminas/metabolismo , Alelos , Creatinina/análise , Diabetes Mellitus Tipo 2/genética , Feminino , Frequência do Gene/genética , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Hipertensão/genética , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Reino Unido , Doenças Vasculares/genética , Doenças Vasculares/metabolismo
8.
Hum Mol Genet ; 28(8): 1392-1401, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30649302

RESUMO

Anti-Müllerian hormone (AMH) is required for sexual differentiation in the fetus, and in adult females AMH is produced by growing ovarian follicles. Consequently, AMH levels are correlated with ovarian reserve, declining towards menopause when the oocyte pool is exhausted. A previous genome-wide association study identified three genetic variants in and around the AMH gene that explained 25% of variation in AMH levels in adolescent males but did not identify any genetic associations reaching genome-wide significance in adolescent females. To explore the role of genetic variation in determining AMH levels in women of late reproductive age, we carried out a genome-wide meta-analysis in 3344 pre-menopausal women from five cohorts (median age 44-48 years at blood draw). A single genetic variant, rs16991615, previously associated with age at menopause, reached genome-wide significance at P = 3.48 × 10-10, with a per allele difference in age-adjusted inverse normal AMH of 0.26 standard deviations (SD) (95% confidence interval (CI) [0.18,0.34]). We investigated whether genetic determinants of female reproductive lifespan were more generally associated with pre-menopausal AMH levels. Genetically-predicted age at menarche had no robust association but genetically-predicted age at menopause was associated with lower AMH levels by 0.18 SD (95% CI [0.14,0.21]) in age-adjusted inverse normal AMH per one-year earlier age at menopause. Our findings provide genetic support for the well-established use of AMH as a marker of ovarian reserve.


Assuntos
Hormônio Antimülleriano/genética , Pré-Menopausa/fisiologia , Adulto , Fatores Etários , Hormônio Antimülleriano/sangue , Hormônio Antimülleriano/fisiologia , Sequência de Bases , Feminino , Expressão Gênica , Regulação da Expressão Gênica/genética , Estudos de Associação Genética/métodos , Variação Genética/genética , Estudo de Associação Genômica Ampla/métodos , Haplótipos , Humanos , Longevidade , Menarca/genética , Pessoa de Meia-Idade , Mitocôndrias/genética , Folículo Ovariano , Ovário , Polimorfismo de Nucleotídeo Único/genética , Pré-Menopausa/genética , Reprodução/genética , Análise de Sequência de DNA , Transcriptoma/genética
9.
Hum Mol Genet ; 27(4): 742-756, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29309628

RESUMO

Genome-wide association studies of birth weight have focused on fetal genetics, whereas relatively little is known about the role of maternal genetic variation. We aimed to identify maternal genetic variants associated with birth weight that could highlight potentially relevant maternal determinants of fetal growth. We meta-analysed data on up to 8.7 million SNPs in up to 86 577 women of European descent from the Early Growth Genetics (EGG) Consortium and the UK Biobank. We used structural equation modelling (SEM) and analyses of mother-child pairs to quantify the separate maternal and fetal genetic effects. Maternal SNPs at 10 loci (MTNR1B, HMGA2, SH2B3, KCNAB1, L3MBTL3, GCK, EBF1, TCF7L2, ACTL9, CYP3A7) were associated with offspring birth weight at P < 5 × 10-8. In SEM analyses, at least 7 of the 10 associations were consistent with effects of the maternal genotype acting via the intrauterine environment, rather than via effects of shared alleles with the fetus. Variants, or correlated proxies, at many of the loci had been previously associated with adult traits, including fasting glucose (MTNR1B, GCK and TCF7L2) and sex hormone levels (CYP3A7), and one (EBF1) with gestational duration. The identified associations indicate that genetic effects on maternal glucose, cytochrome P450 activity and gestational duration, and potentially on maternal blood pressure and immune function, are relevant for fetal growth. Further characterization of these associations in mechanistic and causal analyses will enhance understanding of the potentially modifiable maternal determinants of fetal growth, with the goal of reducing the morbidity and mortality associated with low and high birth weights.


Assuntos
Peso ao Nascer/genética , Estudo de Associação Genômica Ampla/métodos , Polimorfismo de Nucleotídeo Único/genética , Actinas/genética , Proteínas Adaptadoras de Transdução de Sinal , Alelos , Peso ao Nascer/fisiologia , Citocromo P-450 CYP3A/genética , Proteínas de Ligação a DNA/genética , Feminino , Variação Genética/genética , Genótipo , Quinases do Centro Germinativo , Idade Gestacional , Proteína HMGA2/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Canal de Potássio Kv1.3/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas/genética , Receptor MT2 de Melatonina/genética , Transativadores/genética , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética
10.
J Am Chem Soc ; 141(1): 298-308, 2019 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-30525570

RESUMO

Molecular inks based on dimethyl sulfoxide, thiourea (TU), and metal salts have been used to form high optoelectronic quality semiconductors and have led to high power conversion efficiencies for solution-processed photovoltaic devices for Cu2ZnSn(S,Se)4 (CZTS), Cu2Zn(Ge,Sn)(S,Se)4 (CZGTS), CuIn(S,Se)2 (CIS), and Cu(In,Ga)(S,Se)2 (CIGS). However, several metal species of interest, including Ag(I), In(III), Ge(II), and Ge(IV), either have low solubility (requiring dilute inks) or lead to precipitation or gelation. Here, we demonstrate that the combination of N,N-dimethylformamide (DMF) and TU has the remarkable ability to form intermediate-stability acid-base complexes with a wide number of metal chloride Lewis acids (CuCl, AgCl, ZnCl2, InCl3, GaCl3, SnCl4, GeCl4, and SeCl4), to give high-concentration stable molecular inks. Using calorimetry, Raman spectroscopy, and solubility experiments, we reveal the important role of chloride transfer and TU to stabilize metal cations in DMF. Methylation of TU is used to vary the strength of the Lewis basicity and demonstrate that the strength of the TU-metal chloride complex formed after DMF evaporation is critical to prevent volatilization of metal containing species. Further, we formulated a sulfur-free molecular ink which was used to deposit crystalline CuInSe2 without selenization that sustains high quasi-Fermi level splitting under constant illumination. Finally, we demonstrate the ability of the DMF-TU molecular ink chemistry to lead to high-photovoltaic power conversion efficiencies and high-open-circuit voltages for solution-processed CIS and CZGTS with power conversion efficiencies of 13.4% and 11.0% and Voc/ Voc,SQ of 67% and 63%, respectively.

12.
Hum Mol Genet ; 26(5): 1018-1030, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28040731

RESUMO

As genetic association studies increase in size to 100 000s of individuals, subtle biases may influence conclusions. One possible bias is 'index event bias' (IEB) that appears due to the stratification by, or enrichment for, disease status when testing associations between genetic variants and a disease-associated trait. We aimed to test the extent to which IEB influences some known trait associations in a range of study designs and provide a statistical framework for assessing future associations. Analyzing data from 113 203 non-diabetic UK Biobank participants, we observed three (near TCF7L2, CDKN2AB and CDKAL1) overestimated (body mass index (BMI) decreasing) and one (near MTNR1B) underestimated (BMI increasing) associations among 11 type 2 diabetes risk alleles (at P < 0.05). IEB became even stronger when we tested a type 2 diabetes genetic risk score composed of these 11 variants (-0.010 standard deviations BMI per allele, P = 5 × 10- 4), which was confirmed in four additional independent studies. Similar results emerged when examining the effect of blood pressure increasing alleles on BMI in normotensive UK Biobank samples. Furthermore, we demonstrated that, under realistic scenarios, common disease alleles would become associated at P < 5 × 10- 8 with disease-related traits through IEB alone, if disease prevalence in the sample differs appreciably from the background population prevalence. For example, some hypertension and type 2 diabetes alleles will be associated with BMI in sample sizes of >500 000 if the prevalence of those diseases differs by >10% from the background population. In conclusion, IEB may result in false positive or negative genetic associations in very large studies stratified or strongly enriched for/against disease cases.


Assuntos
Diabetes Mellitus Tipo 2/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Hipertensão/genética , Alelos , Glicemia/genética , Índice de Massa Corporal , Genótipo , Humanos , Hipertensão/patologia , Obesidade/genética , Polimorfismo de Nucleotídeo Único
13.
Genet Med ; 21(4): 877-886, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30181606

RESUMO

PURPOSE: Many women with X chromosome aneuploidy undergo lifetime clinical monitoring for possible complications. However, ascertainment of cases in the clinic may mean that the penetrance has been overestimated. METHODS: We characterized the prevalence and phenotypic consequences of X chromosome aneuploidy in a population of 244,848 women over 40 years of age from UK Biobank, using single-nucleotide polymorphism (SNP) array data. RESULTS: We detected 30 women with 45,X; 186 with mosaic 45,X/46,XX; and 110 with 47,XXX. The prevalence of nonmosaic 45,X (12/100,000) and 47,XXX (45/100,000) was lower than expected, but was higher for mosaic 45,X/46,XX (76/100,000). The characteristics of women with 45,X were consistent with the characteristics of a clinically recognized Turner syndrome phenotype, including short stature and primary amenorrhea. In contrast, women with mosaic 45,X/46,XX were less short, had a normal reproductive lifespan and birth rate, and no reported cardiovascular complications. The phenotype of women with 47,XXX included taller stature (5.3 cm; SD = 5.52 cm; P = 5.8 × 10-20) and earlier menopause age (5.12 years; SD = 5.1 years; P = 1.2 × 10-14). CONCLUSION: Our results suggest that the clinical management of women with 45,X/46,XX mosaicism should be minimal, particularly those identified incidentally.


Assuntos
Cromossomos Humanos X/genética , Genética Populacional , Mosaicismo , Síndrome de Turner/genética , Adulto , Idoso , Aneuploidia , Feminino , Humanos , Cariótipo , Pessoa de Meia-Idade , Penetrância , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Trissomia , Síndrome de Turner/patologia , Reino Unido
14.
Eur J Vasc Endovasc Surg ; 57(5): 639-648, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31005508

RESUMO

OBJECTIVE: To report the outcome of elective fenestrated and branch (FEVAR-BEVAR) endovascular aortic repair with supracoeliac (SC) sealing zones and the impact of staged repair without prophylactic cerebrospinal fluid (CSF) drainage on the incidence of spinal cord ischaemia (SCI). METHODS: Two hundred and seventy consecutive patients (217 men; mean [SD] age, 72.8 ± 6.3 years; median (IQR) diameter 65 mm [62-75 mm]) with juxtarenal (JRAAA) (n = 69) or thoraco-abdominal aortic aneurysms (TAAAs) (n = 201) underwent elective FEVAR (n = 192) or BEVAR (n = 78) with renovisceral stent grafting, proximal SC (Zones 1-5; <40 mm [n = 83]; ≥40 mm [n = 187]) and distal infrarenal aorto-iliac sealing zone (Zones 9-11) between December 2008 and September 2017. A spinal cord protection protocol (SCPP) including staging without prophylactic CSF drainage was introduced in September 2012. RESULTS: A total of 1026 renovisceral vessels (mean 3.8 ± 0.5 per patient) were targeted for preservation. One patient (0.4%) died in the institution within 30 days and 31 (11.4%) developed 36 major non-fatal complications including unplanned permanent dialysis (n = 1, 0.4%) and non-ambulatory SCI (n = 6, 2.2%). In patients with <40 mm SC coverage, none were staged or had prophylactic CSF drains and none developed SCI. In patients with ≥40 mm SC coverage, SCI occurred in 3.3% (pre-SCPP: 4/20 [20%; none staged, 13 prophylactic CSF drains] vs. post-SCPP: 2/167 [1.2%; 89 staged, no prophylactic CSF drains]; p = .001 [OR = 19.9]). Estimated survival (±SE) at one, two and three years was 92.6% ± 1.6%, 86.5% ± 2.4%, and 73.8% ± 3.5%, respectively, with no significant difference comparing extent of aneurysm or SC coverage. Forty-three (15.9%) patients required late re-intervention. Estimated freedom from re-intervention at one, two and three years was 91.9% ± 1.8%, 85.1% ± 2.5%, and 79.5% ± 3.2%, respectively. CONCLUSION: Elective endovascular thoraco-abdominal aortic repair with SC sealing zones can be performed with low peri-operative risk and good medium-term outcomes. Selective staging without prophylactic CSF drainage contributed to a significant reduction in the incidence of SCI.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Procedimentos Cirúrgicos Eletivos/métodos , Procedimentos Endovasculares/métodos , Idoso , Vazamento de Líquido Cefalorraquidiano , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Feminino , Seguimentos , Mortalidade Hospitalar , Humanos , Estimativa de Kaplan-Meier , Masculino , Complicações Pós-Operatórias , Reoperação , Estudos Retrospectivos , Isquemia do Cordão Espinal/etiologia , Isquemia do Cordão Espinal/prevenção & controle , Resultado do Tratamento
15.
PLoS Genet ; 12(8): e1006125, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27494321

RESUMO

Disrupted circadian rhythms and reduced sleep duration are associated with several human diseases, particularly obesity and type 2 diabetes, but until recently, little was known about the genetic factors influencing these heritable traits. We performed genome-wide association studies of self-reported chronotype (morning/evening person) and self-reported sleep duration in 128,266 white British individuals from the UK Biobank study. Sixteen variants were associated with chronotype (P<5x10-8), including variants near the known circadian rhythm genes RGS16 (1.21 odds of morningness, 95% CI [1.15, 1.27], P = 3x10-12) and PER2 (1.09 odds of morningness, 95% CI [1.06, 1.12], P = 4x10-10). The PER2 signal has previously been associated with iris function. We sought replication using self-reported data from 89,283 23andMe participants; thirteen of the chronotype signals remained associated at P<5x10-8 on meta-analysis and eleven of these reached P<0.05 in the same direction in the 23andMe study. We also replicated 9 additional variants identified when the 23andMe study was used as a discovery GWAS of chronotype (all P<0.05 and meta-analysis P<5x10-8). For sleep duration, we replicated one known signal in PAX8 (2.6 minutes per allele, 95% CI [1.9, 3.2], P = 5.7x10-16) and identified and replicated two novel associations at VRK2 (2.0 minutes per allele, 95% CI [1.3, 2.7], P = 1.2x10-9; and 1.6 minutes per allele, 95% CI [1.1, 2.2], P = 7.6x10-9). Although we found genetic correlation between chronotype and BMI (rG = 0.056, P = 0.05); undersleeping and BMI (rG = 0.147, P = 1x10-5) and oversleeping and BMI (rG = 0.097, P = 0.04), Mendelian Randomisation analyses, with limited power, provided no consistent evidence of causal associations between BMI or type 2 diabetes and chronotype or sleep duration. Our study brings the total number of loci associated with chronotype to 22 and with sleep duration to three, and provides new insights into the biology of sleep and circadian rhythms in humans.


Assuntos
Ritmo Circadiano/genética , Diabetes Mellitus Tipo 2/genética , Fator de Transcrição PAX8/genética , Proteínas Serina-Treonina Quinases/genética , Sono/genética , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/patologia , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Análise da Randomização Mendeliana , Obesidade/genética , Obesidade/patologia , Sono/fisiologia , População Branca
16.
J Water Health ; 16(1): 70-77, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29424720

RESUMO

In microbiological water quality testing, sample dechlorination with sodium thiosulfate is recommended to ensure that results accurately reflect the water quality at sample collection. Nevertheless, monitoring institutions in low-resource settings do not always dechlorinate samples, and there is limited research describing how this practice impacts drinking water quality results. The effect of dechlorination on indicator bacteria counts was evaluated by spiking laboratory water with five Escherichia coli (E. coli) concentrations (104-108 CFU/100 mL), chlorinating at six doses (0-0.6 mg/L), holding samples with and without sodium thiosulfate for 5-7 hours, and enumerating E. coli by membrane filtration with m-lauryl sulfate media. Additionally, sub-Saharan African water suppliers enumerated thermotolerant coliform by membrane filtration in paired chlorinated water samples collected with and without sodium thiosulfate. Across all E. coli and chlorine doses in the laboratory, and all field tests, samples held without sodium thiosulfate had lower bacteria counts (p < 0.001). Additionally, chlorinated water supply samples held without sodium thiosulfate had an 87.5% false negative rate. Results indicate the importance of dechlorinating microbiological water quality samples, discarding data from chlorinated samples collected without dechlorination, and reinforcing dechlorination recommendations in resource-limited environments to improve water safety management.


Assuntos
Cloro/química , Água Potável/química , Escherichia coli/isolamento & purificação , Fezes/microbiologia , Tiossulfatos/química , Microbiologia da Água , Purificação da Água/métodos , Qualidade da Água , África Subsaariana , Halogenação
17.
Zoo Biol ; 37(1): 23-34, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29210099

RESUMO

We investigated how forage material affects indicators of welfare in three male Western lowland gorillas (Gorilla gorilla gorilla) at the Detroit Zoo. In addition to their maintenance diet and enrichment foods, the gorillas generally received forage material four times a week. From this baseline, we systematically manipulated how much forage material the group received on a weekly basis, with either daily or bi (twice)-weekly presentation of browse (mulberry, Morus sp.) or alfalfa hay. We collected behavioral data (60 hr per gorilla) and measured fecal glucocorticoid metabolites (FGM). Mixed models indicated that the presence of forage material significantly increased time feeding (F2,351 = 9.58, p < 0.001), and decreased rates of noncontact aggression (F2,351 = 3.69, p = 0.03), and regurgitation and reingestion (F2,353 = 4.70, p = 0.01). Regurgitation and reingestion were never observed during the condition when forage material was provided daily. When forage material was provided, time spent feeding was similar across gorillas, compared to a disproportionately greater amount of time spent feeding by the dominant individual when forage material was absent. Providing forage material in addition to the regular diet likely created more opportunities for equitable feeding for the subordinate gorillas. FGM concentrations did not vary based on the presence or type of forage material available and, instead, likely reflected group social dynamics. In general, alfalfa and mulberry had similar impacts on behavior, indicating that alfalfa can be an adequate behavioral substitute during times when browse is less readily available for gorillas housed in seasonally variable climates.


Assuntos
Ração Animal/análise , Comportamento Animal , Glucocorticoides/metabolismo , Gorilla gorilla , Medicago sativa , Morus , Criação de Animais Domésticos , Animais , Animais de Zoológico , Fezes/química , Glucocorticoides/química , Masculino , Atividade Motora
18.
Hum Mol Genet ; 24(5): 1504-12, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25378555

RESUMO

Initial results from sequencing studies suggest that there are relatively few low-frequency (<5%) variants associated with large effects on common phenotypes. We performed low-pass whole-genome sequencing in 680 individuals from the InCHIANTI study to test two primary hypotheses: (i) that sequencing would detect single low-frequency-large effect variants that explained similar amounts of phenotypic variance as single common variants, and (ii) that some common variant associations could be explained by low-frequency variants. We tested two sets of disease-related common phenotypes for which we had statistical power to detect large numbers of common variant-common phenotype associations-11 132 cis-gene expression traits in 450 individuals and 93 circulating biomarkers in all 680 individuals. From a total of 11 657 229 high-quality variants of which 6 129 221 and 5 528 008 were common and low frequency (<5%), respectively, low frequency-large effect associations comprised 7% of detectable cis-gene expression traits [89 of 1314 cis-eQTLs at P < 1 × 10(-06) (false discovery rate ∼5%)] and one of eight biomarker associations at P < 8 × 10(-10). Very few (30 of 1232; 2%) common variant associations were fully explained by low-frequency variants. Our data show that whole-genome sequencing can identify low-frequency variants undetected by genotyping based approaches when sample sizes are sufficiently large to detect substantial numbers of common variant associations, and that common variant associations are rarely explained by single low-frequency variants of large effect.


Assuntos
Estudos de Associação Genética/métodos , Marcadores Genéticos , Fenótipo , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Frequência do Gene , Variação Genética , Genoma Humano , Técnicas de Genotipagem , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Adulto Jovem
19.
J Water Health ; 15(1): 72-82, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28151441

RESUMO

Locally manufactured ceramic water filters are one effective household drinking water treatment technology. During manufacturing, silver nanoparticles or silver nitrate are applied to prevent microbiological growth within the filter and increase bacterial removal efficacy. Currently, there is no recommendation for manufacturers to test silver concentrations of application solutions or filtered water. We identified six commercially available silver test strips, kits, and meters, and evaluated them by: (1) measuring in quintuplicate six samples from 100 to 1,000 mg/L (application range) and six samples from 0.0 to 1.0 mg/L (effluent range) of silver nanoparticles and silver nitrate to determine accuracy and precision; (2) conducting volunteer testing to assess ease-of-use; and (3) comparing costs. We found no method accurately detected silver nanoparticles, and accuracy ranged from 4 to 91% measurement error for silver nitrate samples. Most methods were precise, but only one method could test both application and effluent concentration ranges of silver nitrate. Volunteers considered test strip methods easiest. The cost for 100 tests ranged from 36 to 1,600 USD. We found no currently available method accurately and precisely measured both silver types at reasonable cost and ease-of-use, thus these methods are not recommended to manufacturers. We recommend development of field-appropriate methods that accurately and precisely measure silver nanoparticle and silver nitrate concentrations.


Assuntos
Cerâmica/análise , Filtração/métodos , Prata/química , Purificação da Água/métodos , Cerâmica/economia , Custos e Análise de Custo , Filtração/economia , Filtração/instrumentação , Prata/economia , Purificação da Água/economia , Purificação da Água/instrumentação
20.
Diabetologia ; 59(6): 1214-21, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26961502

RESUMO

AIMS/HYPOTHESIS: Genome-wide association (GWA) studies have identified hundreds of common genetic variants associated with obesity and type 2 diabetes. These studies have usually focused on additive association tests. Identifying deviations from additivity may provide new biological insights and explain some of the missing heritability for these diseases. METHODS: We performed a GWA study using a dominance deviation model for BMI, obesity (29,925 cases) and type 2 diabetes (4,040 cases) in 120,286 individuals of British ancestry from the UK Biobank study. We also investigated whether single nucleotide polymorphisms previously shown to be associated with these traits showed any enrichment for departures from additivity. RESULTS: Known obesity-associated variants in FTO showed strong evidence of deviation from additivity (p DOMDEV = 3 × 10(-5)) through a recessive effect of the allele associated with higher BMI. The average BMI of individuals carrying zero, one or two BMI-raising alleles was 27.27 (95% CI 27.22, 27.31) kg/m(2), 27.54 (95% CI 27.50, 27.58) kg/m(2) and 28.07 (95% CI 28.00, 28.14) kg/m(2), respectively. A similar effect was observed in 105,643 individuals from the GIANT Consortium (p DOMDEV = 0.003; meta-analysis p DOMDEV = 1 × 10(-7)). For type 2 diabetes, we detected a recessive effect (p DOMDEV = 5 × 10(-4)) at CDKAL1. Relative to homozygous non-risk allele carriers, homozygous risk allele carriers had an OR of 1.48 (95% CI 1.32, 1.65), while the heterozygous group had an OR of 1.06 (95% CI 0.99, 1.14), a result consistent with that of a previous study. We did not identify any novel associations at genome-wide significance. CONCLUSIONS/INTERPRETATION: Although we found no evidence of widespread non-additive genetic effects contributing to obesity and type 2 diabetes risk, we did find robust examples of recessive effects at the FTO and CDKAL1 loci. ACCESS TO RESEARCH MATERIALS: Summary statistics are available at www.t2diabetesgenes.org and by request (a.r.wood@exeter.ac.uk). All underlying data are available on application from the UK Biobank.


Assuntos
Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Diabetes Mellitus Tipo 2/genética , tRNA Metiltransferases/genética , Alelos , Índice de Massa Corporal , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Modelos Estatísticos , Obesidade/genética , Polimorfismo de Nucleotídeo Único/genética , Análise de Componente Principal
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