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1.
Disasters ; 43(4): 771-798, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31475408

RESUMO

This paper outlines why a move towards a complex adaptive systems model of behaviour is required if the goal is to generate better understanding of how individuals and groups interact with their environment in a disaster setting. To accomplish this objective, a bridge must be built between the broader social sciences and behavioural economics to incorporate discipline-specific insights that are needed to move towards complexity. This is only possible through a deeper understanding of behaviour and how the environment in which they occur can influence actions. It is then that one can counteract the poor behavioural predictions, flawed policies based on myth, inefficient design, and suboptimal outcomes that have flourished in the absence of a complex adaptive systems model. This paper provides a conceptual framework that draws on concepts from across the natural and social sciences, such as behavioural economics, endocrinology, psychology, sociobiology, and sociology in order to build an interactive theory of disaster behaviour.


Assuntos
Comportamento , Desastres , Modelos Psicológicos , Humanos
2.
Reprod Biomed Online ; 35(6): 723-732, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28951001

RESUMO

As informal sperm donation becomes more prevalent worldwide, understanding donor psychology and interactions is critical in providing effective policy, equitable legislative frameworks and frontline health support to an ever-growing number of global participants. We analyse data of informal sperm donors who were members of the connection website PrideAngel to identify the role and effect of several factors, e.g. kinship, social networks, personality, and risk perception, on behaviour. A key strength of the study is the ability to analyse various factors, such as the level and history of informal donation, risk concerns, number of women to whom donations are informally made and the number of offspring. Our results indicate donors who have also been active in formal clinical settings (compared with those who exclusively donate informally), donate to more women in the informal market and realise more offspring. Donor's sexual orientation also affects activity. From a personality perspective, conscientiousness provides comparative advantage. It is possible this characteristic provides positive externalities, as more conscientious men may be more efficient or organised in a market that requires increased cooperation and communication. The importance of kin and social networks seems to affect frequency of donation only, possibly representing a time constraint (or opportunity cost).


Assuntos
Setor Informal , Espermatozoides , Doadores de Tecidos/psicologia , Adulto , Idoso , Família , Amigos , Humanos , Inseminação Artificial Heteróloga , Internet , Masculino , Pessoa de Meia-Idade , Personalidade , Adulto Jovem
3.
Nat Genet ; 38(6): 617-9, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16699517

RESUMO

In this study we report convincing statistical support for a sixth type 1 diabetes (T1D) locus in the innate immunity viral RNA receptor gene region IFIH1 (also known as mda-5 or Helicard) on chromosome 2q24.3. We found the association in an interim analysis of a genome-wide nonsynonymous SNP (nsSNP) scan, and we validated it in a case-control collection and replicated it in an independent family collection. In 4,253 cases, 5,842 controls and 2,134 parent-child trio genotypes, the risk ratio for the minor allele of the nsSNP rs1990760 A --> G (A946T) was 0.86 (95% confidence interval = 0.82-0.90) at P = 1.42 x 10(-10).


Assuntos
Diabetes Mellitus Tipo 1/genética , Genoma Humano , Polimorfismo de Nucleotídeo Único , RNA Helicases/genética , Cromossomos Humanos Par 2 , RNA Helicases DEAD-box , Genótipo , Humanos , Helicase IFIH1 Induzida por Interferon
4.
J Am Soc Nephrol ; 24(4): 627-37, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23520204

RESUMO

Lipoxins, which are endogenously produced lipid mediators, promote the resolution of inflammation, and may inhibit fibrosis, suggesting a possible role in modulating renal disease. Here, lipoxin A4 (LXA4) attenuated TGF-ß1-induced expression of fibronectin, N-cadherin, thrombospondin, and the notch ligand jagged-1 in cultured human proximal tubular epithelial (HK-2) cells through a mechanism involving upregulation of the microRNA let-7c. Conversely, TGF-ß1 suppressed expression of let-7c. In cells pretreated with LXA4, upregulation of let-7c persisted despite subsequent stimulation with TGF-ß1. In the unilateral ureteral obstruction model of renal fibrosis, let-7c upregulation was induced by administering an LXA4 analog. Bioinformatic analysis suggested that targets of let-7c include several members of the TGF-ß1 signaling pathway, including the TGF-ß receptor type 1. Consistent with this, LXA4-induced upregulation of let-7c inhibited both the expression of TGF-ß receptor type 1 and the response to TGF-ß1. Overexpression of let-7c mimicked the antifibrotic effects of LXA4 in renal epithelia; conversely, anti-miR directed against let-7c attenuated the effects of LXA4. Finally, we observed that several let-7c target genes were upregulated in fibrotic human renal biopsies compared with controls. In conclusion, these results suggest that LXA4-mediated upregulation of let-7c suppresses TGF-ß1-induced fibrosis and that expression of let-7c targets is dysregulated in human renal fibrosis.


Assuntos
Rim/efeitos dos fármacos , Rim/patologia , Lipoxinas/farmacologia , MicroRNAs/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Caderinas/efeitos dos fármacos , Caderinas/metabolismo , Células Cultivadas , Fibronectinas/efeitos dos fármacos , Fibronectinas/metabolismo , Fibrose , Humanos , Rim/metabolismo , Túbulos Renais Proximais/efeitos dos fármacos , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/patologia , MicroRNAs/efeitos dos fármacos , Receptor Notch1/efeitos dos fármacos , Receptor Notch1/metabolismo , Transdução de Sinais , Trombospondinas/efeitos dos fármacos , Trombospondinas/metabolismo , Fator de Crescimento Transformador beta1/efeitos dos fármacos
5.
Sci Rep ; 14(1): 1790, 2024 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245576

RESUMO

During the COVID-19 pandemic, several governments tried to contain the spread of SARS-CoV-2, the virus that causes COVID-19, with lockdowns that prohibited leaving one's residence unless carrying out a few essential services. We investigate the relationship between limitations to mobility and mental health in the UK during the first year and a half of the pandemic using a unique combination of high-frequency mobility data from Google and monthly longitudinal data collected through the Understanding Society survey. We find a strong and statistically robust correlation between mobility data and mental health survey data and show that increased residential stationarity is associated with the deterioration of mental wellbeing even when regional COVID-19 prevalence and lockdown stringency are controlled for. The relationship is heterogeneous, as higher levels of distress are seen in young, healthy people living alone; and in women, especially if they have young children.


Assuntos
COVID-19 , Criança , Humanos , Feminino , Pré-Escolar , COVID-19/epidemiologia , SARS-CoV-2 , Pandemias , Controle de Doenças Transmissíveis , Avaliação de Resultados em Cuidados de Saúde , Reino Unido/epidemiologia
6.
Genome Res ; 20(4): 440-6, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20219944

RESUMO

Polycomb group proteins (PCGs) are involved in repression of genes that are required for stem cell differentiation. Recently, it was shown that promoters of PCG target genes (PCGTs) are 12-fold more likely to be methylated in cancer than non-PCGTs. Age is the most important demographic risk factor for cancer, and we hypothesized that its carcinogenic potential may be referred by irreversibly stabilizing stem cell features. To test this, we analyzed the methylation status of over 27,000 CpGs mapping to promoters of approximately 14,000 genes in whole blood samples from 261 postmenopausal women. We demonstrate that stem cell PCGTs are far more likely to become methylated with age than non-targets (odds ratio = 5.3 [3.8-7.4], P < 10(-10)), independently of sex, tissue type, disease state, and methylation platform. We identified a specific subset of 69 PCGT CpGs that undergo hypermethylation with age and validated this methylation signature in seven independent data sets encompassing over 900 samples, including normal and cancer solid tissues and a population of bone marrow mesenchymal stem/stromal cells (P < 10(-5)). We find that the age-PCGT methylation signature is present in preneoplastic conditions and may drive gene expression changes associated with carcinogenesis. These findings shed substantial novel insights into the epigenetic effects of aging and support the view that age may predispose to malignant transformation by irreversibly stabilizing stem cell features.


Assuntos
Envelhecimento/genética , Metilação de DNA , Inativação Gênica/fisiologia , Genes , Neoplasias/genética , Células-Tronco/metabolismo , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Metilação de DNA/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Regulação Neoplásica da Expressão Gênica , Genes/fisiologia , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/metabolismo , Regiões Promotoras Genéticas , Estudos de Validação como Assunto , Adulto Jovem
7.
BMC Nephrol ; 14: 126, 2013 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-23777469

RESUMO

BACKGROUND: Renal interstitial fibrosis and glomerular sclerosis are hallmarks of diabetic nephropathy (DN) and several studies have implicated members of the WNT pathways in these pathological processes. This study comprehensively examined common genetic variation within the WNT pathway for association with DN. METHODS: Genes within the WNT pathways were selected on the basis of nominal significance and consistent direction of effect in the GENIE meta-analysis dataset. Common SNPs and common haplotypes were examined within the selected WNT pathway genes in a white population with type 1 diabetes, discordant for DN (cases: n = 718; controls: n = 749). SNPs were genotyped using Sequenom or Taqman assays. Association analyses were performed using PLINK, to compare allele and haplotype frequencies in cases and controls. Correction for multiple testing was performed by either permutation testing or using false discovery rate. RESULTS: A logistic regression model including collection centre, duration of diabetes, and average HbA1c as covariates highlighted three SNPs in GSK3B (rs17810235, rs17471, rs334543), two in DAAM1 (rs1253192, rs1252906) and one in NFAT5 (rs17297207) as being significantly (P < 0.05) associated with DN, however these SNPs did not remain significant after correction for multiple testing. Logistic regression of haplotypes, with ESRD as the outcome, and pairwise interaction analyses did not yield any significant results after correction for multiple testing. CONCLUSIONS: These results indicate that both common SNPs and common haplotypes of WNT pathway genes are not strongly associated with DN. However, this does not completely exclude these or the WNT pathways from association with DN, as unidentified rare genetic or copy number variants could still contribute towards the genetic architecture of DN.


Assuntos
Nefropatias Diabéticas/diagnóstico , Nefropatias Diabéticas/genética , Estudos de Associação Genética/métodos , Haplótipos/genética , Via de Sinalização Wnt/genética , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética
8.
Proc Natl Acad Sci U S A ; 107(11): 4862-5, 2010 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-20194743

RESUMO

To understand human behavior, it is important to know under what conditions people deviate from selfish rationality. This study explores the interaction of natural survival instincts and internalized social norms using data on the sinking of the Titanic and the Lusitania. We show that time pressure appears to be crucial when explaining behavior under extreme conditions of life and death. Even though the two vessels and the composition of their passengers were quite similar, the behavior of the individuals on board was dramatically different. On the Lusitania, selfish behavior dominated (which corresponds to the classical homo economicus); on the Titanic, social norms and social status (class) dominated, which contradicts standard economics. This difference could be attributed to the fact that the Lusitania sank in 18 min, creating a situation in which the short-run flight impulse dominated behavior. On the slowly sinking Titanic (2 h, 40 min), there was time for socially determined behavioral patterns to reemerge. Maritime disasters are traditionally not analyzed in a comparative manner with advanced statistical (econometric) techniques using individual data of the passengers and crew. Knowing human behavior under extreme conditions provides insight into how widely human behavior can vary, depending on differing external conditions.


Assuntos
Desastres , Instinto , Navios , Comportamento Social , Sobrevida , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Adulto Jovem
9.
J Am Soc Nephrol ; 21(5): 773-81, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20150533

RESUMO

Gremlin, a cell growth and differentiation factor, promotes the development of diabetic nephropathy in animal models, but whether GREM1 gene variants associate with diabetic nephropathy is unknown. We comprehensively screened the 5' upstream region (including the predicted promoter), all exons, intron-exon boundaries, complete untranslated regions, and the 3' region downstream of the GREM1 gene. We identified 31 unique variants, including 24 with a minor allele frequency exceeding 5%, and 9 haplotype-tagging single nucleotide polymorphisms (htSNPs). We selected one additional variant that we predicted to alter transcription factor binding. We genotyped 709 individuals with type 1 diabetes of whom 267 had nephropathy (cases) and 442 had no evidence of kidney disease (controls). Three individual SNPs significantly associated with nephropathy at the 5% level, and two remained significant after adjustment for multiple testing. Subsequently, we genotyped a replicate population comprising 597 cases and 502 controls: this population supported an association with one of the SNPs (rs1129456; P = 0.0003). Combined analysis, adjusted for recruitment center (n = 8), suggested that the T allele conferred greater odds of nephropathy (OR 1.69; 95% CI 1.36 to 2.11). In summary, the GREM1 variant rs1129456 associates with diabetic nephropathy, perhaps explaining some of the genetic susceptibility to this condition.


Assuntos
Nefropatias Diabéticas/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Polimorfismo de Nucleotídeo Único , Adulto , Sequência de Aminoácidos , Sequência de Bases , Estudos de Casos e Controles , Frequência do Gene , Genótipo , Humanos , Desequilíbrio de Ligação , Pessoa de Meia-Idade , Dados de Sequência Molecular , Alinhamento de Sequência
10.
Rev Econ Househ ; 19(1): 123-144, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33456425

RESUMO

The COVID-19 pandemic and the policy measures to control its spread-lockdowns, physical distancing, and social isolation-have coincided with the deterioration of people's mental well-being. We use data from the UK Household Longitudinal Study (UKHLS) to document how this phenomenon is related to the situation of working parents who now have to manage competing time demands across the two life domains of work and home. We show that the deterioration of mental health is worse for working parents, and that it is strongly related to increased financial insecurity and time spent on childcare and home schooling. This burden is not shared equally between men and women, and between richer and poorer households. These inequalities ought to be taken into account when crafting policy responses.

11.
Sci Rep ; 10(1): 19931, 2020 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-33199737

RESUMO

Behavioural responses to pandemics are less shaped by actual mortality or hospitalisation risks than they are by risk attitudes. We explore human mobility patterns as a measure of behavioural responses during the COVID-19 pandemic. Our results indicate that risk-taking attitudes are a critical factor in predicting reductions in human mobility and social confinement around the globe. We find that the sharp decline in mobility after the WHO (World Health Organization) declared COVID-19 to be a pandemic can be attributed to risk attitudes. Our results suggest that regions with risk-averse attitudes are more likely to adjust their behavioural activity in response to the declaration of a pandemic even before official government lockdowns. Further understanding of the basis of responses to epidemics, e.g., precautionary behaviour, will help improve the containment of the spread of the virus.


Assuntos
COVID-19/psicologia , Locomoção , Pandemias/estatística & dados numéricos , Assunção de Riscos , Atitude Frente a Saúde , COVID-19/epidemiologia , Comércio/estatística & dados numéricos , Aglomeração , Humanos , Atividades de Lazer , Meios de Transporte/estatística & dados numéricos , Viagem/estatística & dados numéricos
12.
PLoS One ; 15(10): e0240644, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33057450

RESUMO

Confidence in the health care system implies an expectation that sufficient and appropriate treatments will be provided if needed. The COVID-19 public health crisis is a significant, global, and (mostly) simultaneous test of the behavioral implications arising from this confidence. We explore whether populations reporting low levels of confidence in the health care system exhibit a stronger behavioral reaction to the COVID-19 pandemic. We track the dynamic responses to the COVID-19 pandemic across 38 European countries and 621 regions by employing a large dataset on human mobility generated between February 15 and June 5, 2020 and a broad range of contextual factors (e.g., deaths or policy implementations). Using a time-dynamic framework we find that societies with low levels of health care confidence initially exhibit a faster response with respect to staying home. However, this reaction plateaus sooner, and after the plateau it declines with greater magnitude than does the response from societies with high health care confidence. On the other hand, regions with higher confidence in the health care system are more likely to reduce mobility once the government mandates that its citizens are not to leave home except for essential trips, compared to those with lower health care system confidence. Regions with high trust in the government but low confidence in the health care system dramatically reduce their mobility, suggesting a correlation for trust in the state with respect to behavioral responses during a crisis.


Assuntos
Atitude Frente a Saúde , Infecções por Coronavirus/psicologia , Movimento , Pneumonia Viral/psicologia , Quarentena/psicologia , Confiança , COVID-19 , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Europa (Continente) , Humanos , Pandemias/prevenção & controle , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Viagem/estatística & dados numéricos
13.
Nephrol Dial Transplant ; 24(8): 2473-6, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19336575

RESUMO

BACKGROUND: Diabetic nephropathy is a leading cause of end-stage renal disease. Premature mortality is common in patients with nephropathy, largely due to cardiovascular disease. Genetic variants implicated in macrovascular disease are therefore excellent candidates to assess for association with diabetic nephropathy. Recent genome-wide association studies have identified a total of 15 single-nucleotide polymorphisms (SNPs) that are reproducibly associated with cardiovascular disease. METHODS: We initially assessed these SNPs for association in UK type 1 diabetic patients with (cases; n = 597) and without (controls; n = 502) nephropathy using iPLEX(TM) and TaqMan(R) assays. Replication studies were performed with DNA genotyped in a total of 2668 individuals from the British Isles. RESULTS: One SNP (rs4420638) on chromosome 19q13 was found to be significantly associated with diabetic nephropathy before (P = 0.0002) and after correction for multiple testing (P(corrected) = 0.002). We replicated this finding in a phenotypically similar case-control collection comprising 709 individuals with type 1 diabetes (P = 0.002; combined P < 0.00001; OR = 1.54, 95% CI: 1.29-1.84). CONCLUSIONS: Our case-control data suggest that rs4420638, or a functional SNP in linkage disequilibrium with this SNP, may be associated with diabetic nephropathy.


Assuntos
Doença da Artéria Coronariana/genética , Diabetes Mellitus Tipo 1/genética , Nefropatias Diabéticas/genética , Repetições de Microssatélites/genética , Polimorfismo de Nucleotídeo Único/genética , Adolescente , Adulto , Idade de Início , Estudos de Casos e Controles , Feminino , Genoma Humano , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Reino Unido , Adulto Jovem
14.
BMC Med Genet ; 8: 5, 2007 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-17319955

RESUMO

BACKGROUND: Diabetic nephropathy is the leading cause of end stage renal failure in the western world. There is substantial epidemiological evidence supporting a genetic predisposition to diabetic nephropathy, however the exact molecular mechanisms remain unknown. Transforming growth factor (TGFbeta1) is a crucial mediator in the pathogenesis of diabetic nephropathy. METHODS: We investigated the role of five known single nucleotide polymorphisms (SNPs) in the TGFB1 gene for their association with diabetic nephropathy in an Irish, type 1 diabetic case (n = 272) control (n = 367) collection. The activity of TGFbeta1 is facilitated by the action of type 1 and type 2 receptors, with both receptor genes (TGFBR1 and TGFBR2) shown to be upregulated in diabetic kidney disease. We therefore screened TGFBR1 and TGFBR2 genes for genomic variants using WAVEtrade mark (dHPLC) technology and confirmed variants by direct capillary sequencing. Allele frequencies were determined in forty-eight healthy individuals. Data for all SNPs was assessed for Hardy Weinberg equilibrium, with genotypes and allele frequencies compared using the chi2 test for contingency tables. Patterns of linkage disequilibrium were established and common haplotypes estimated. RESULTS: Fifteen variants were identified in these genes, seven of which are novel, and putatively functional SNPs were subsequently genotyped using TaqMantrade mark, Invadertrade mark or Pyrosequencing(R) technology. No significant differences (p > 0.1) were found in genotype or allele distributions between cases and controls for any of the SNPs assessed. CONCLUSION: Our results suggest common variants in TGFB1, TGFBR1 and TGFBR2 genes do not strongly influence genetic susceptibility to diabetic nephropathy in an Irish Caucasian population.


Assuntos
Receptores de Ativinas Tipo I/genética , Diabetes Mellitus Tipo 1/genética , Nefropatias Diabéticas/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Fator de Crescimento Transformador beta1/genética , Adolescente , Adulto , Estudos de Casos e Controles , Análise Mutacional de DNA , Feminino , Genótipo , Humanos , Masculino , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Proteínas Serina-Treonina Quinases , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptor do Fator de Crescimento Transformador beta Tipo II
15.
J Diabetes Complications ; 21(4): 242-5, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17616354

RESUMO

Vascular endothelial growth factor (VEGF) is reported to be implicated in the development of diabetic nephropathy. We performed a case-control study to determine if VEGF-2578C-->A, VEGF-1499C-->T, and VEGF-635G-->C single-nucleotide polymorphisms (SNPs) in the VEGF gene are associated with predisposition to diabetic nephropathy in type 1 diabetes. Genomic DNA was obtained from Irish type 1 diabetic individuals with nephropathy (cases, n=242) and those without nephropathy (controls, n=301), in addition to 400 healthy control samples. These samples were genotyped for the three SNPs using TaqMan or Pyrosequencing technology. Chi-squared analyses revealed no significant differences in genotype or allele frequencies in cases versus controls for VEGF-2578C-->A (genotype, P=.58; allele, P=.52) and VEGF-635G-->C (genotype, P=.58; allele, P=.33). However, a positive association with diabetic nephropathy was observed for the VEGF-1499T allele in the Northern Ireland population (P <.001) and subsequently replicated in a separate population from the Republic of Ireland (P <.001; combined, P <.001). Carriage of the VEGF-1499T allele was associated with a twofold excess risk of developing diabetic nephropathy (OR=2.24, 95% CI=1.50-3.36, P <.0001). No significant differences were found between the healthy control population and the type 1 diabetic population. Our results suggest that the VEGF-1499T allele, or an allele in linkage disequilibrium with this allele, is associated with susceptibility to diabetic nephropathy in the Irish population.


Assuntos
Citidina/genética , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/genética , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/genética , Polimorfismo de Nucleotídeo Único/genética , Fator A de Crescimento do Endotélio Vascular/genética , Adolescente , Alelos , Estudos de Casos e Controles , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 1/patologia , Nefropatias Diabéticas/epidemiologia , Nefropatias Diabéticas/patologia , Genótipo , Humanos , Timidina/genética
16.
Nephron Exp Nephrol ; 105(3): e75-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17220636

RESUMO

BACKGROUND/AIMS: The Hp(1)/Hp(2) DNA polymorphism has previously been implicated in susceptibility to diabetic nephropathy in some but not all studies. In an attempt to clarify these conflicting findings, we conducted a case-control association study in a Caucasian population. METHODS: We recruited 224 and 285 type 1 diabetic patients with (cases) and without (controls) nephropathy, respectively, from 2 centres based in Northern Ireland and the Republic of Ireland. Hp(1)/Hp(2) genotyping was performed using a combination of long-range and multiplex PCR. Allele and genotype frequencies in cases and controls were compared using the chi(2) test. RESULTS: There was a statistically significant increase in the frequency of the Hp(2) allele in cases compared to controls (65.6 vs. 58.6%, OR = 1.35, 95% CI: 1.04-1.76, p = 0.03). The distributions of genotypes were in Hardy-Weinberg equilibrium for both cases and controls, and the overall frequency of the Hp(1) allele was 38.3%, which is similar to that found in other Western European populations. CONCLUSIONS: The results suggest that the Hp(2) allele may confer susceptibility to nephropathy in patients with type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 1/genética , Nefropatias Diabéticas/epidemiologia , Nefropatias Diabéticas/genética , Haptoglobinas/genética , Polimorfismo de Nucleotídeo Único/genética , Medição de Risco/métodos , Adolescente , Comorbidade , Análise Mutacional de DNA , Feminino , Predisposição Genética para Doença/epidemiologia , Predisposição Genética para Doença/genética , Variação Genética/genética , Humanos , Irlanda/epidemiologia , Masculino , Prevalência , Fatores de Risco
17.
Diabetes ; 53(4): 1162-5, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15047636

RESUMO

Dysfunction of the actin cytoskeleton is a key event in the pathogenesis of diabetic nephropathy. We previously reported that certain cytoskeletal genes are upregulated in mesangial cells exposed to a high extracellular glucose concentration. One such gene, caldesmon, lies on chromosome 7q35, a region linked to nephropathy in family studies, making it a candidate susceptibility gene for diabetic nephropathy. We screened all exons, untranslated regions, and a 5-kb region upstream of the gene for variation using denaturing high-performance liquid chromatography technology. An A>G single nucleotide polymorphism (SNP) at position -579 in the promoter region was associated with nephropathy in a case-control study using 393 type 1 diabetic patients from Northern Ireland (odds ratio [OR] 1.38, 95% CI 1.02-1.86, P = 0.03). A similar trend was found in an independent sample from a second center. When the sample groups were combined (n = 606), the association between the -579G allele and nephropathy remained significant (OR 1.35, 1.07-1.70, P = 0.01). The haplotype structure in the surrounding 7-kb region was determined. No single haplotype was more strongly associated with nephropathy than the -579A>G SNP. These results suggest a role for the caldesmon gene in susceptibility to diabetic nephropathy in type 1 diabetes.


Assuntos
Proteínas de Ligação a Calmodulina/genética , Diabetes Mellitus Tipo 1/genética , Nefropatias Diabéticas/genética , Variação Genética , Polimorfismo de Nucleotídeo Único/genética , Sequência de Bases , Predisposição Genética para Doença/genética , Genótipo , Humanos , Irlanda , Irlanda do Norte , Razão de Chances , Regiões Promotoras Genéticas/genética
18.
Diabetes ; 53(4): 1158-61, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15047635

RESUMO

Variation in genes necessary for normal functioning and development of beta-cells, e.g., NEUROD1, which encodes a transcription factor for the insulin gene and is important in beta-cell development, causes maturity-onset diabetes of the young. Some studies have reported an association between a nonsynonymous Ala(45)Thr (+182G-->A) single nucleotide polymorphism (SNP) in NEUROD1 and type 1 diabetes, but this result has not been consistently found. To clarify this, we genotyped Ala(45)Thr in 2,434 type 1 diabetic families of European descent and Caucasian ethnicity from five different countries. Taking the allele frequency of 36% for Thr(45) and an odds ratio (OR) of 1.2, this sample provided >99% power to detect an association (P < 0.05). We could not confirm the association (P = 0.77). No evidence of population heterogeneity in the lack of association of Thr(45) with type 1 diabetes was observed. To evaluate the possibility that another NEUROD1 variant was associated with type 1 diabetes, we resequenced the gene in 32 U.K. affected individuals and identified and genotyped all common SNPs (minor allele frequency >10%; n = 5) in 786 families. We report no evidence of association of these common variants in NEUROD1 and type 1 diabetes in these samples.


Assuntos
Diabetes Mellitus Tipo 1/genética , Proteínas do Tecido Nervoso/genética , Polimorfismo de Nucleotídeo Único/genética , Substituição de Aminoácidos , Sequência de Bases , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Primers do DNA , Variação Genética , Genótipo , Proteínas de Homeodomínio/genética , Humanos , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Fatores de Transcrição/genética
19.
Diabetes ; 53(3): 870-3, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14988278

RESUMO

It has been proposed that type 1 and 2 diabetes might share common pathophysiological pathways and, to some extent, genetic background. However, to date there has been no convincing data to establish a molecular genetic link between them. We have genotyped three single nucleotide polymorphisms associated with type 2 diabetes in a large type 1 diabetic family collection of European descent: Gly972Arg in the insulin receptor substrate 1 (IRS1) gene, Glu23Lys in the potassium inwardly-rectifying channel gene (KCNJ11), and Pro12Ala in the peroxisome proliferative-activated receptor gamma2 gene (PPARG2). We were unable to confirm a recently published association of the IRS1 Gly972Arg variant with type 1 diabetes. Moreover, KCNJ11 Glu23Lys showed no association with type 1 diabetes (P > 0.05). However, the PPARG2 Pro12Ala variant showed evidence of association (RR 1.15, 95% CI 1.04-1.28, P = 0.008). Additional studies need to be conducted to confirm this result.


Assuntos
Diabetes Mellitus Tipo 1/genética , Fosfoproteínas/genética , Polimorfismo de Nucleotídeo Único/genética , Canais de Potássio Corretores do Fluxo de Internalização/genética , Receptores Citoplasmáticos e Nucleares/genética , Fatores de Transcrição/genética , Adulto , Substituição de Aminoácidos , Canadá , Criança , Diabetes Mellitus Tipo 2/genética , Europa (Continente) , Feminino , Humanos , Proteínas Substratos do Receptor de Insulina , Masculino
20.
Diabetes ; 53(9): 2479-82, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15331563

RESUMO

Prior data associating the expression of lymphocyte-specific protein tyrosine kinase (LCK) with type 1 diabetes, its critical function in lymphocytes, and the linkage of the region to diabetes in the nonobese diabetic (NOD) mouse model make LCK a premier candidate for a susceptibility gene. Resequencing of LCK in 32 individuals detected seven single nucleotide polymorphisms (SNPs) with allele frequencies >3%, including four common SNPs previously reported. These and six other SNPs from dbSNP were genotyped in a two-stage strategy using 2,430 families and were all shown not to be significantly associated with type 1 diabetes. We conclude that a major role for the common LCK polymorphisms in type 1 diabetes is unlikely. However, we cannot rule out the possibility of there being a causal variant outside the exonic, intronic, and untranslated regions studied.


Assuntos
Diabetes Mellitus Tipo 1/genética , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/genética , Adulto , Criança , Predisposição Genética para Doença , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único
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