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1.
Nature ; 607(7920): 732-740, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35859178

RESUMO

Detailed knowledge of how diversity in the sequence of the human genome affects phenotypic diversity depends on a comprehensive and reliable characterization of both sequences and phenotypic variation. Over the past decade, insights into this relationship have been obtained from whole-exome sequencing or whole-genome sequencing of large cohorts with rich phenotypic data1,2. Here we describe the analysis of whole-genome sequencing of 150,119 individuals from the UK Biobank3. This constitutes a set of high-quality variants, including 585,040,410 single-nucleotide polymorphisms, representing 7.0% of all possible human single-nucleotide polymorphisms, and 58,707,036 indels. This large set of variants allows us to characterize selection based on sequence variation within a population through a depletion rank score of windows along the genome. Depletion rank analysis shows that coding exons represent a small fraction of regions in the genome subject to strong sequence conservation. We define three cohorts within the UK Biobank: a large British Irish cohort, a smaller African cohort and a South Asian cohort. A haplotype reference panel is provided that allows reliable imputation of most variants carried by three or more sequenced individuals. We identified 895,055 structural variants and 2,536,688 microsatellites, groups of variants typically excluded from large-scale whole-genome sequencing studies. Using this formidable new resource, we provide several examples of trait associations for rare variants with large effects not found previously through studies based on whole-exome sequencing and/or imputation.


Assuntos
Bancos de Espécimes Biológicos , Bases de Dados Genéticas , Variação Genética , Genoma Humano , Genômica , Sequenciamento Completo do Genoma , África/etnologia , Ásia/etnologia , Estudos de Coortes , Sequência Conservada , Éxons/genética , Genoma Humano/genética , Haplótipos/genética , Humanos , Mutação INDEL , Irlanda/etnologia , Repetições de Microssatélites , Polimorfismo de Nucleotídeo Único/genética , Reino Unido
2.
Eur Heart J ; 44(12): 1070-1080, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36747475

RESUMO

AIMS: Syncope is a common and clinically challenging condition. In this study, the genetics of syncope were investigated to seek knowledge about its pathophysiology and prognostic implications. METHODS AND RESULTS: This genome-wide association meta-analysis included 56 071 syncope cases and 890 790 controls from deCODE genetics (Iceland), UK Biobank (United Kingdom), and Copenhagen Hospital Biobank Cardiovascular Study/Danish Blood Donor Study (Denmark), with a follow-up assessment of variants in 22 412 cases and 286 003 controls from Intermountain (Utah, USA) and FinnGen (Finland). The study yielded 18 independent syncope variants, 17 of which were novel. One of the variants, p.Ser140Thr in PTPRN2, affected syncope only when maternally inherited. Another variant associated with a vasovagal reaction during blood donation and five others with heart rate and/or blood pressure regulation, with variable directions of effects. None of the 18 associations could be attributed to cardiovascular or other disorders. Annotation with regard to regulatory elements indicated that the syncope variants were preferentially located in neural-specific regulatory regions. Mendelian randomization analysis supported a causal effect of coronary artery disease on syncope. A polygenic score (PGS) for syncope captured genetic correlation with cardiovascular disorders, diabetes, depression, and shortened lifespan. However, a score based solely on the 18 syncope variants performed similarly to the PGS in detecting syncope risk but did not associate with other disorders. CONCLUSION: The results demonstrate that syncope has a distinct genetic architecture that implicates neural regulatory processes and a complex relationship with heart rate and blood pressure regulation. A shared genetic background with poor cardiovascular health was observed, supporting the importance of a thorough assessment of individuals presenting with syncope.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus , Humanos , Estudo de Associação Genômica Ampla/métodos , Síncope/genética , Doenças Cardiovasculares/genética , Sistema Nervoso Autônomo , Análise da Randomização Mendeliana
3.
Ann Rheum Dis ; 82(6): 873-880, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36931692

RESUMO

OBJECTIVES: Erosive hand osteoarthritis (EHOA) is a severe subset of hand osteoarthritis (OA). It is unclear if EHOA is genetically different from other forms of OA. Sequence variants at ten loci have been associated with hand OA but none with EHOA. METHODS: We performed meta-analysis of EHOA in 1484 cases and 550 680 controls, from 5 populations. To identify causal genes, we performed eQTL and plasma pQTL analyses, and developed one zebrafish mutant. We analysed associations of variants with other traits and estimated shared genetics between EHOA and other traits. RESULTS: Four common sequence variants associated with EHOA, all with relatively high effect. Rs17013495 (SPP1/MEPE, OR=1.40, p=8.4×10-14) and rs11243284 (6p24.3, OR=1.35, p=4.2×10-11) have not been associated with OA, whereas rs11631127 (ALDH1A2, OR=1.46, p=7.1×10-18), and rs1800801 (MGP, OR=1.37, p=3.6×10-13) have previously been associated with hand OA. The association of rs1800801 (MGP) was consistent with a recessive mode of inheritance in contrast to its additive association with hand OA (OR homozygotes vs non-carriers=2.01, 95% CI 1.71 to 2.37). All four variants associated nominally with finger OA, although with substantially lower effect. We found shared genetic components between EHOA and other OA measures, grip strength, urate levels and gout, but not rheumatoid arthritis. We identified ALDH1A2, MGP and BMP6 as causal genes for EHOA, with loss-of-function Bmp6 zebrafish mutants displaying EHOA-like phenotypes. CONCLUSIONS: We report on significant genetic associations with EHOA. The results support the view of EHOA as a form of severe hand OA and partly separate it from OA in larger joints.


Assuntos
Artrite Reumatoide , Articulação da Mão , Osteoartrite , Animais , Articulação da Mão/diagnóstico por imagem , Peixe-Zebra/genética , Mãos , Osteoartrite/complicações , Artrite Reumatoide/complicações
4.
Br J Cancer ; 115(7): 776-83, 2016 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-27537391

RESUMO

BACKGROUND: The impact of an inherited BRCA2 mutation on the prognosis of women with breast cancer has not been well documented. We studied the effects of oestrogen receptor (ER) status, other prognostic factors and treatments on survival in a large cohort of BRCA2 mutation carriers. METHODS: We identified 285 breast cancer patients with a 999del5 BRCA2 mutation and matched them with 570 non-carrier patients. Clinical information was abstracted from patient charts and pathology records and supplemented by evaluation of tumour grade and ER status using archived tissue specimens. Univariate and multivariate hazard ratios (HR) were estimated for breast cancer-specific survival using Cox regression. The effects of various therapies were studied in patients treated from 1980 to 2012. RESULTS: Among mutation carriers, positive ER status was associated with higher risk of death than negative ER status (HR=1.94; 95% CI=1.22-3.07, P=0.005). The reverse association was seen for non-carriers (HR=0.71; 95% CI: 0.51-0.97; P=0.03). CONCLUSIONS: Among BRCA2 carriers, ER-positive status is an adverse prognostic factor. BRCA2 carrier status should be known at the time when treatment decisions are made.


Assuntos
Neoplasias da Mama/genética , Estrogênios , Genes BRCA2 , Mutação , Neoplasias Hormônio-Dependentes/genética , Síndromes Neoplásicas Hereditárias/genética , Receptores de Estrogênio/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/química , Neoplasias da Mama/mortalidade , Neoplasias da Mama/terapia , Feminino , Humanos , Islândia/epidemiologia , Masculino , Pessoa de Meia-Idade , Neoplasias Hormônio-Dependentes/química , Neoplasias Hormônio-Dependentes/mortalidade , Neoplasias Hormônio-Dependentes/terapia , Segunda Neoplasia Primária/epidemiologia , Segunda Neoplasia Primária/genética , Síndromes Neoplásicas Hereditárias/mortalidade , Síndromes Neoplásicas Hereditárias/terapia , Prognóstico , Modelos de Riscos Proporcionais , Resultado do Tratamento , Adulto Jovem
5.
Breast Cancer Res ; 16(3): 307, 2014 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-25927994

RESUMO

In a recent article, Wang and colleagues reported the discovery of a mechanism by which CARM1 regulates the genomic localization of BAF155 (a SWI/SNF subunit involved in chromatin remodeling) through post-translational methylation at R1064 arginine residues. This modification leads to the relocalization of BAF155-containing SWI/SNF complexes to regions containing genes involved in the Myc oncogenic pathway. The results presented are evidence that these interactions constitute a mechanism by which the BAF155 chromatin remodeling factor contributes to cancer.


Assuntos
Neoplasias da Mama/metabolismo , Regulação Neoplásica da Expressão Gênica/fisiologia , Proteína-Arginina N-Metiltransferases/metabolismo , Fatores de Transcrição/metabolismo , Animais , Feminino , Humanos
6.
Am J Pathol ; 183(4): 1052-1063, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23899662

RESUMO

In cancer, the overall patterns of epigenetic marks are severely distorted from the corresponding normal cell type. It is now well established that these changes can contribute to cancer development through inactivation of tumor suppressor genes and, conversely, through activation of oncogenes. Recent technological advances have enabled epigenome-wide analyses of cancers that are yielding unexpected findings. The study of cancer epigenetics holds great promise for expanding the range of therapeutic opportunities for personalized medicine. Here, we focus on DNA methylation in breast cancer and the potential implications for clinical management of patients.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/terapia , Epigênese Genética , Medicina de Precisão , Proteína BRCA1/genética , Metilação de DNA/genética , Feminino , Humanos , Mutação/genética
7.
Genome Biol ; 25(1): 69, 2024 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-38468278

RESUMO

BACKGROUND: Long-read sequencing can enable the detection of base modifications, such as CpG methylation, in single molecules of DNA. The most commonly used methods for long-read sequencing are nanopore developed by Oxford Nanopore Technologies (ONT) and single molecule real-time (SMRT) sequencing developed by Pacific Bioscience (PacBio). In this study, we systematically compare the performance of CpG methylation detection from long-read sequencing. RESULTS: We demonstrate that CpG methylation detection from 7179 nanopore-sequenced DNA samples is highly accurate and consistent with 132 oxidative bisulfite-sequenced (oxBS) samples, isolated from the same blood draws. We introduce quality filters for CpGs that further enhance the accuracy of CpG methylation detection from nanopore-sequenced DNA, while removing at most 30% of CpGs. We evaluate the per-site performance of CpG methylation detection across different genomic features and CpG methylation rates and demonstrate how the latest R10.4 flowcell chemistry and base-calling algorithms improve methylation detection from nanopore sequencing. Additionally, we show how the methylation detection of 50 SMRT-sequenced genomes compares to nanopore sequencing and oxBS. CONCLUSIONS: This study provides the first systematic comparison of CpG methylation detection tools for long-read sequencing methods. We compare two commonly used computational methods for the detection of CpG methylation in a large number of nanopore genomes, including samples sequenced using the latest R10.4 nanopore flowcell chemistry and 50 SMRT sequenced samples. We provide insights into the strengths and limitations of each sequencing method as well as recommendations for standardization and evaluation of tools designed for genome-scale modified base detection using long-read sequencing.


Assuntos
Metilação de DNA , Genoma Humano , Humanos , Análise de Sequência de DNA/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , DNA
8.
Commun Biol ; 7(1): 504, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671141

RESUMO

Essential tremor (ET) is a prevalent neurological disorder with a largely unknown underlying biology. In this genome-wide association study meta-analysis, comprising 16,480 ET cases and 1,936,173 controls from seven datasets, we identify 12 sequence variants at 11 loci. Evaluating mRNA expression, splicing, plasma protein levels, and coding effects, we highlight seven putative causal genes at these loci, including CA3 and CPLX1. CA3 encodes Carbonic Anhydrase III and carbonic anhydrase inhibitors have been shown to decrease tremors. CPLX1, encoding Complexin-1, regulates neurotransmitter release. Through gene-set enrichment analysis, we identify a significant association with specific cell types, including dopaminergic and GABAergic neurons, as well as biological processes like Rho GTPase signaling. Genetic correlation analyses reveals a positive association between ET and Parkinson's disease, depression, and anxiety-related phenotypes. This research uncovers risk loci, enhancing our knowledge of the complex genetics of this common but poorly understood disorder, and highlights CA3 and CPLX1 as potential therapeutic targets.


Assuntos
Tremor Essencial , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Tremor Essencial/genética , Humanos , Polimorfismo de Nucleotídeo Único , Loci Gênicos
9.
JAMA Cardiol ; 9(2): 165-172, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38150231

RESUMO

Importance: Recurrent pericarditis is a treatment challenge and often a debilitating condition. Drugs inhibiting interleukin 1 cytokines are a promising new treatment option, but their use is based on scarce biological evidence and clinical trials of modest sizes, and the contributions of innate and adaptive immune processes to the pathophysiology are incompletely understood. Objective: To use human genomics, transcriptomics, and proteomics to shed light on the pathogenesis of pericarditis. Design, Setting, and Participants: This was a meta-analysis of genome-wide association studies of pericarditis from 5 countries. Associations were examined between the pericarditis-associated variants and pericarditis subtypes (including recurrent pericarditis) and secondary phenotypes. To explore mechanisms, associations with messenger RNA expression (cis-eQTL), plasma protein levels (pQTL), and CpG methylation of DNA (ASM-QTL) were assessed. Data from Iceland (deCODE genetics, 1983-2020), Denmark (Copenhagen Hospital Biobank/Danish Blood Donor Study, 1977-2022), the UK (UK Biobank, 1953-2021), the US (Intermountain, 1996-2022), and Finland (FinnGen, 1970-2022) were included. Data were analyzed from September 2022 to August 2023. Exposure: Genotype. Main Outcomes and Measures: Pericarditis. Results: In this genome-wide association study of 4894 individuals with pericarditis (mean [SD] age at diagnosis, 51.4 [17.9] years, 2734 [67.6%] male, excluding the FinnGen cohort), associations were identified with 2 independent common intergenic variants at the interleukin 1 locus on chromosome 2q14. The lead variant was rs12992780 (T) (effect allele frequency [EAF], 31%-40%; odds ratio [OR], 0.83; 95% CI, 0.79-0.87; P = 6.67 × 10-16), downstream of IL1B and the secondary variant rs7575402 (A or T) (EAF, 45%-55%; adjusted OR, 0.89; 95% CI, 0.85-0.93; adjusted P = 9.6 × 10-8). The lead variant rs12992780 had a smaller odds ratio for recurrent pericarditis (0.76) than the acute form (0.86) (P for heterogeneity = .03) and rs7575402 was associated with CpG methylation overlapping binding sites of 4 transcription factors known to regulate interleukin 1 production: PU.1 (encoded by SPI1), STAT1, STAT3, and CCAAT/enhancer-binding protein ß (encoded by CEBPB). Conclusions and Relevance: This study found an association between pericarditis and 2 independent sequence variants at the interleukin 1 gene locus. This finding has the potential to contribute to development of more targeted and personalized therapy of pericarditis with interleukin 1-blocking drugs.


Assuntos
Estudo de Associação Genômica Ampla , Humanos , Masculino , Adolescente , Feminino , Genótipo , Fenótipo , Frequência do Gene , Finlândia
10.
Carcinogenesis ; 34(1): 102-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23054610

RESUMO

Using whole blood from 15 twin pairs discordant for breast cancer and high-resolution (450K) DNA methylation analysis, we identified 403 differentially methylated CpG sites including known and novel potential breast cancer genes. Confirming the results in an independent validation cohort of 21 twin pairs determined the docking protein DOK7 as a candidate for blood-based cancer diagnosis. DNA hypermethylation of the promoter region was also seen in primary breast cancer tissues and cancer cell lines. Hypermethylation of DOK7 occurs years before tumor diagnosis, suggesting a role as a powerful epigenetic blood-based biomarker as well as providing insights into breast cancer pathogenesis.


Assuntos
Biomarcadores/metabolismo , Neoplasias da Mama/genética , Metilação de DNA , Epigênese Genética , Proteínas Musculares/genética , Estudos em Gêmeos como Assunto , Feminino , Humanos
11.
Breast Cancer Res Treat ; 140(2): 375-84, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23857704

RESUMO

It is not well known to what extent carrying a BRCA2 mutation affects the survival of women with breast cancer and prognostic factors among BRCA2-positive women warrant investigation. Using a record linkage approach we compared the long-term survival in carriers and noncarriers of an inherited BRCA2 founder mutation (999del5), and sought to identify prognostic factors among the BRCA2 mutation-positive subset, including markers of genetic instability (aneuploidy) and mitotic activity (S-phase fraction). We established the genetic status of 2,967 Icelandic breast cancer patients (215 mutation carriers and 2,752 noncarriers) diagnosed from 1955 to 2004, representing 72 % of all cases diagnosed in the country during this period. Tumour ploidy and S-phase fraction were assessed on tumour cells by DNA flow cytometry. Prognostic factors were assessed blindly with respect to mutation status. Univariate and multivariate hazard ratios (HR) were estimated for breast cancer-specific survival by BRCA2 status, using Cox regression. After a median follow-up of 9.5 years, BRCA2 mutation carriers had a higher risk of death from breast cancer than noncarriers (HR 1.64, 95 % CI 1.24-2.16, p < 0.001). The risk increase was restricted to women with diploid tumours (HR 3.03, 95 % CI 1.91-4.79, p < 0.001). Among breast cancer patients with aneuploid tumours, survival of carriers was similar to that of noncarriers (HR 0.76, 95 % CI 0.41-1.41, p = 0.38). Increased tumour size and a positive nodal status predicted worse prognosis in all patients, whereas the highly correlated prognostic factors diploidy, low proliferative activity and a positive estrogen receptor status had reverse effects in mutation carriers and noncarriers. Breast cancer patients who carry the Icelandic founder BRCA2 mutation have inferior long-term survival than noncarriers, but the adverse prognosis is restricted to mutation carriers with diploid, slowly proliferating tumours.


Assuntos
Proteína BRCA2/genética , Neoplasias da Mama/genética , Diploide , Análise de Sobrevida , Adulto , Idoso , Neoplasias da Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Mutação , Prognóstico
12.
Nat Commun ; 14(1): 3855, 2023 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-37386006

RESUMO

Microsatellites are polymorphic tracts of short tandem repeats with one to six base-pair (bp) motifs and are some of the most polymorphic variants in the genome. Using 6084 Icelandic parent-offspring trios we estimate 63.7 (95% CI: 61.9-65.4) microsatellite de novo mutations (mDNMs) per offspring per generation, excluding one bp repeats motifs (homopolymers) the estimate is 48.2 mDNMs (95% CI: 46.7-49.6). Paternal mDNMs occur at longer repeats than maternal ones, which are in turn larger with a mean size of 3.4 bp vs 3.1 bp for paternal ones. mDNMs increase by 0.97 (95% CI: 0.90-1.04) and 0.31 (95% CI: 0.25-0.37) per year of father's and mother's age at conception, respectively. Here, we find two independent coding variants that associate with the number of mDNMs transmitted to offspring; The minor allele of a missense variant (allele frequency (AF) = 1.9%) in MSH2, a mismatch repair gene, increases transmitted mDNMs from both parents (effect: 13.1 paternal and 7.8 maternal mDNMs). A synonymous variant (AF = 20.3%) in NEIL2, a DNA damage repair gene, increases paternally transmitted mDNMs (effect: 4.4 mDNMs). Thus, the microsatellite mutation rate in humans is in part under genetic control.


Assuntos
Reparo de Erro de Pareamento de DNA , Mutação em Linhagem Germinativa , Humanos , Alelos , Mutação em Linhagem Germinativa/genética , Repetições de Microssatélites/genética , Células Germinativas
13.
medRxiv ; 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37645979

RESUMO

Bleeding in early pregnancy and postpartum hemorrhage (PPH) bear substantial risks, with the former closely associated with pregnancy loss and the latter being the foremost cause of maternal death, underscoring the severity of these complications in maternal-fetal health. Here, we investigated the genetic variation underlying aspects of pregnancy-associated bleeding and identified five loci associated with PPH through a meta-analysis of 21,512 cases and 259,500 controls. Functional annotation analysis indicated candidate genes, HAND2, TBX3, and RAP2C/FRMD7, at three loci and showed that at each locus, associated variants were located within binding sites for progesterone receptors (PGR). Furthermore, there were strong genetic correlations with birth weight, gestational duration, and uterine fibroids. Early bleeding during pregnancy (28,898 cases and 302,894 controls) yielded no genome-wide association signals, but showed strong genetic correlation with a variety of human traits, indicative of polygenic and pleiotropic effects. Our results suggest that postpartum bleeding is related to myometrium dysregulation, whereas early bleeding is a complex trait related to underlying health and possibly socioeconomic status.

14.
Nat Commun ; 14(1): 3453, 2023 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-37301908

RESUMO

Genotypes causing pregnancy loss and perinatal mortality are depleted among living individuals and are therefore difficult to find. To explore genetic causes of recessive lethality, we searched for sequence variants with deficit of homozygosity among 1.52 million individuals from six European populations. In this study, we identified 25 genes harboring protein-altering sequence variants with a strong deficit of homozygosity (10% or less of predicted homozygotes). Sequence variants in 12 of the genes cause Mendelian disease under a recessive mode of inheritance, two under a dominant mode, but variants in the remaining 11 have not been reported to cause disease. Sequence variants with a strong deficit of homozygosity are over-represented among genes essential for growth of human cell lines and genes orthologous to mouse genes known to affect viability. The function of these genes gives insight into the genetics of intrauterine lethality. We also identified 1077 genes with homozygous predicted loss-of-function genotypes not previously described, bringing the total set of genes completely knocked out in humans to 4785.


Assuntos
Proteínas , Humanos , Animais , Camundongos , Homozigoto , Genótipo , Proteínas/genética , Genes Recessivos
15.
Nat Genet ; 55(11): 1843-1853, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37884687

RESUMO

Migraine is a complex neurovascular disease with a range of severity and symptoms, yet mostly studied as one phenotype in genome-wide association studies (GWAS). Here we combine large GWAS datasets from six European populations to study the main migraine subtypes, migraine with aura (MA) and migraine without aura (MO). We identified four new MA-associated variants (in PRRT2, PALMD, ABO and LRRK2) and classified 13 MO-associated variants. Rare variants with large effects highlight three genes. A rare frameshift variant in brain-expressed PRRT2 confers large risk of MA and epilepsy, but not MO. A burden test of rare loss-of-function variants in SCN11A, encoding a neuron-expressed sodium channel with a key role in pain sensation, shows strong protection against migraine. Finally, a rare variant with cis-regulatory effects on KCNK5 confers large protection against migraine and brain aneurysms. Our findings offer new insights with therapeutic potential into the complex biology of migraine and its subtypes.


Assuntos
Epilepsia , Transtornos de Enxaqueca , Enxaqueca com Aura , Humanos , Estudo de Associação Genômica Ampla , Transtornos de Enxaqueca/genética , Enxaqueca com Aura/genética , Fenótipo
16.
Breast Cancer Res ; 13(5): R95, 2011 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-21958427

RESUMO

BACKGROUND: Inherited mutations in the BRCA2 gene greatly increase the risk of developing breast cancer. Consistent with an important role for BRCA2 in error-free DNA repair, complex genomic changes are frequently observed in tumors derived from BRCA2 mutation carriers. Here, we explore the impact of DNA copy-number changes in BRCA2 tumors with respect to phenotype and clinical staging of the disease. METHODS: Breast tumors (n = 33) derived from BRCA2 999del5 mutation carriers were examined in terms of copy-number changes with high-resolution aCGH (array comparative genomic hybridization) containing 385 thousand probes (about one for each 7 kbp) and expression of phenotypic markers on TMAs (tissue microarrays). The data were examined with respect to clinical parameters including TNM staging, histologic grade, S phase, and ploidy. RESULTS: Tumors from BRCA2 carriers of luminal and basal/triple-negative phenotypes (TNPs) differ with respect to patterns of DNA copy-number changes. The basal/TNP subtype was characterized by lack of pRb (RB1) coupled with high/intense expression of p16 (CDKN2A) gene products. We found increased proportions of Ki-67-positive cells to be significantly associated with loss of the wild-type (wt) BRCA2 allele in luminal types, whereas BRCA2wt loss was less frequent in BRCA2 tumors displaying basal/TNP phenotypes. Furthermore, we show that deletions at 13q13.1, involving the BRCA2wt allele, represents a part of a larger network of co-occurring genetic changes, including deletions at 6q22.32-q22.33, 11q14.2-q24.1, and gains at 17q24.1. Importantly, copy-number changes at these BRCA2-linked networking regions coincide with those associated with advanced progression, involving the capacity to metastasize to the nodes or more-distant sites at diagnosis. CONCLUSIONS: The results presented here demonstrate divergent paths of tumor evolution in BRCA2 carriers and that deletion of the wild-type BRCA2 allele, together with co-occurring changes at 6 q, 11 q, and 17 q, are important events in progression toward advanced disease.


Assuntos
Proteína BRCA2/genética , Neoplasias da Mama/genética , Neoplasias da Mama/etiologia , Neoplasias da Mama/patologia , Deleção Cromossômica , Cromossomos Humanos Par 11 , Cromossomos Humanos Par 13 , Cromossomos Humanos Par 17 , Cromossomos Humanos Par 6 , Hibridização Genômica Comparativa , Progressão da Doença , Feminino , Dosagem de Genes , Genes p16 , Humanos , Antígeno Ki-67/metabolismo , Mutação , Fenótipo , Ploidias
17.
Nat Genet ; 53(1): 27-34, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33414551

RESUMO

Despite the important role that monozygotic twins have played in genetics research, little is known about their genomic differences. Here we show that monozygotic twins differ on average by 5.2 early developmental mutations and that approximately 15% of monozygotic twins have a substantial number of these early developmental mutations specific to one of them. Using the parents and offspring of twins, we identified pre-twinning mutations. We observed instances where a twin was formed from a single cell lineage in the pre-twinning cell mass and instances where a twin was formed from several cell lineages. CpG>TpG mutations increased in frequency with embryonic development, coinciding with an increase in DNA methylation. Our results indicate that allocations of cells during development shapes genomic differences between monozygotic twins.


Assuntos
Genoma Humano , Células Germinativas/metabolismo , Gêmeos Monozigóticos/genética , Desenvolvimento Embrionário/genética , Feminino , Frequência do Gene/genética , Humanos , Masculino , Mosaicismo , Mutação/genética , Zigoto/metabolismo
18.
Nat Genet ; 53(6): 779-786, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33972781

RESUMO

Long-read sequencing (LRS) promises to improve the characterization of structural variants (SVs). We generated LRS data from 3,622 Icelanders and identified a median of 22,636 SVs per individual (a median of 13,353 insertions and 9,474 deletions). We discovered a set of 133,886 reliably genotyped SV alleles and imputed them into 166,281 individuals to explore their effects on diseases and other traits. We discovered an association of a rare deletion in PCSK9 with lower low-density lipoprotein (LDL) cholesterol levels, compared to the population average. We also discovered an association of a multiallelic SV in ACAN with height; we found 11 alleles that differed in the number of a 57-bp-motif repeat and observed a linear relationship between the number of repeats carried and height. These results show that SVs can be accurately characterized at the population scale using LRS data in a genome-wide non-targeted approach and demonstrate how SVs impact phenotypes.


Assuntos
Doença/genética , Variação Estrutural do Genoma , Sequenciamento de Nucleotídeos em Larga Escala , Característica Quantitativa Herdável , Alelos , LDL-Colesterol/metabolismo , Cromossomos Humanos/genética , Feminino , Frequência do Gene/genética , Humanos , Islândia , Modelos Lineares , Masculino , Pró-Proteína Convertase 9/genética , Recombinação Genética/genética , Deleção de Sequência/genética
19.
JNCI Cancer Spectr ; 4(2): pkz100, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32175521

RESUMO

BACKGROUND: Breast Cancer 1 gene (BRCA1) is known to be inactivated in breast tumors by promoter methylation. Tumor cells in patients carrying a germline mutation in BRCA1 are sensitive to cytotoxic drugs that cause DNA double strand breaks. However, very little is known on whether patients with BRCA1 promoter methylated tumors are similarly sensitive to cytotoxic drugs. In this study, we address this by making use of extensive follow-up data on patients treated with cyclophosphamide, methotrexate, and fluorouracil in Iceland between 1976 and 2007. METHODS: We analyzed BRCA1 promoter methylation by pyrosequencing DNA from tumor samples from 1031 patients with primary breast cancer. Of those, 965 were sporadic cases, 61 were BRCA2, and five were BRCA1 germline mutation carriers. All cases were examined with respect to clinicopathological parameters and breast cancer-specific survival in patients treated with cytotoxic drugs. Information on chemotherapy treatment in noncarriers was available for 26 BRCA1 methylated tumors and 857 unmethylated tumors. RESULTS: BRCA1 was promoter methylated in 29 sporadic tumors or in 3.0% of cases (29 of 965), whereas none of the tumors derived from BRCA germline mutation carriers were promoter methylated. Important to note, patients with BRCA1 promoter methylation receiving chemotherapeutic drug treatment show highly improved breast cancer-specific survival compared with unmethylated controls (hazard ratio = 0.10, 95% confidence interval = 0.01 to 0.75, two-sided P = .02). CONCLUSIONS: BRCA1 promoter methylation is predictive of improved disease outcome in patients receiving cyclophosphamide, methotrexate, and fluorouracil drug treatment. Our results support the use of markers indicative of "BRCAness" in sporadic breast cancers to identify patients that are likely to benefit from the use of DNA-damaging agents.

20.
Commun Biol ; 3(1): 129, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32184442

RESUMO

Pelvic organ prolapse (POP) is a downward descent of one or more of the pelvic organs, resulting in a protrusion of the vaginal wall and/or uterus. We performed a genome-wide association study of POP using data from Iceland and the UK Biobank, a total of 15,010 cases with hospital-based diagnosis code and 340,734 female controls, and found eight sequence variants at seven loci associating with POP (P < 5 × 10-8); seven common (minor allele frequency >5%) and one with minor allele frequency of 4.87%. Some of the variants associating with POP also associated with traits of similar pathophysiology. Of these, rs3820282, which may alter the estrogen-based regulation of WNT4, also associates with leiomyoma of uterus, gestational duration and endometriosis. Rs3791675 at EFEMP1, a gene involved in connective tissue homeostasis, also associates with hernias and carpal tunnel syndrome. Our results highlight the role of connective tissue metabolism and estrogen exposure in the etiology of POP.


Assuntos
Proteínas da Matriz Extracelular/genética , Loci Gênicos , Polimorfismo de Nucleotídeo Único , Prolapso Uterino/genética , Proteína Wnt4/genética , Índice de Massa Corporal , Estudos de Casos e Controles , Comorbidade , Feminino , Frequência do Gene , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Islândia/epidemiologia , Fenótipo , Medição de Risco , Fatores de Risco , Reino Unido/epidemiologia , Prolapso Uterino/diagnóstico , Prolapso Uterino/epidemiologia
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