scholarly journals Missingness in the T1DGC MHC fine-mapping SNP data: association with HLA genotype and potential influence on genetic association studies

2009 ◽  
Vol 11 ◽  
pp. 101-107 ◽  
Author(s):  
I. James ◽  
E. McKinnon ◽  
S. Gaudieri ◽  
G. Morahan ◽  
2016 ◽  
Author(s):  
Benjamin W. Domingue ◽  
Daniel W. Belsky ◽  
Amal Harrati ◽  
Dalton Conley ◽  
David Weir ◽  
...  

AbstractMortality selection is a general concern in the social and health sciences. Recently, existing health and social science cohorts have begun to collect genomic data. Causes of selection into a genomic dataset can influence results from genomic analyses. Selective non-participation, which is specific to a particular study and its participants, has received attention in the literature. But mortality selection—the very general phenomenon that genomic data collected at a particular age represents selective participation by only the subset of birth cohort members who have survived to the time of data collection—has been largely ignored. Here we test the hypothesis that such mortality selection may significantly alter estimates in polygenetic association studies of both health and non-health traits. We demonstrate mortality selection into genome-wide SNP data collection at older ages using the U.S.-based Health and Retirement Study (HRS). We then model the selection process. Finally, we test whether mortality selection alters estimates from genetic association studies. We find evidence for mortality selection. Healthier and more socioeconomically advantaged individuals are more likely to survive to be eligible to participate in the genetic sample of the HRS. Mortality selection leads to modest drift in estimating time-varying genetic effects, a drift that is enhanced when estimates are produced from data that has additional mortality selection. There is no general solution for correcting for mortality selection in a birth cohort prior to entry into a longitudinal study. We illustrate how genetic association studies using HRS data can adjust for mortality selection from study entry to time of genetic data collection by including probability weights that account for mortality selection. Mortality selection should be investigated more broadly in genetically-informed samples from other cohort studies.


2017 ◽  
Vol 30 (12) ◽  
pp. 1684-1688 ◽  
Author(s):  
José Luis Zepeda-Batista ◽  
Luis Antonio Saavedra-Jiménez ◽  
Agustín Ruíz-Flores ◽  
Rafael Núñez-Domínguez ◽  
Rodolfo Ramírez-Valverde

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kevin K. Esoh ◽  
Tobias O. Apinjoh ◽  
Steven G. Nyanjom ◽  
Ambroise Wonkam ◽  
Emile R. Chimusa ◽  
...  

AbstractInferences from genetic association studies rely largely on the definition and description of the underlying populations that highlight their genetic similarities and differences. The clustering of human populations into subgroups (population structure) can significantly confound disease associations. This study investigated the fine-scale genetic structure within Cameroon that may underlie disparities observed with Cameroonian ethnicities in malaria genome-wide association studies in sub-Saharan Africa. Genotype data of 1073 individuals from three regions and three ethnic groups in Cameroon were analyzed using measures of genetic proximity to ascertain fine-scale genetic structure. Model-based clustering revealed distinct ancestral proportions among the Bantu, Semi-Bantu and Foulbe ethnic groups, while haplotype-based coancestry estimation revealed possible longstanding and ongoing sympatric differentiation among individuals of the Foulbe ethnic group, and their Bantu and Semi-Bantu counterparts. A genome scan found strong selection signatures in the HLA gene region, confirming longstanding knowledge of natural selection on this genomic region in African populations following immense disease pressure. Signatures of selection were also observed in the HBB gene cluster, a genomic region known to be under strong balancing selection in sub-Saharan Africa due to its co-evolution with malaria. This study further supports the role of evolution in shaping genomes of Cameroonian populations and reveals fine-scale hierarchical structure among and within Cameroonian ethnicities that may impact genetic association studies in the country.


2007 ◽  
Vol 16 (20) ◽  
pp. 2494-2505 ◽  
Author(s):  
Yasuhito Nannya ◽  
Kenjiro Taura ◽  
Mineo Kurokawa ◽  
Shigeru Chiba ◽  
Seishi Ogawa

2018 ◽  
Vol 65 (2) ◽  
pp. 241-250 ◽  
Author(s):  
Maciej Michał Kowalik ◽  
Romuald Lango ◽  
Piotr Siondalski ◽  
Magdalena Chmara ◽  
Maciej Brzeziński ◽  
...  

There is increasing evidence that genetic variability influence patients’ early morbidity after cardiac surgery performed using cardiopulmonary bypass (CPB). The use of mortality as an outcome measure in cardiac surgical genetic association studies is rare. We publish the 30-day and 5-year survival analyses with focus on pre-, intra-, postoperative variables, biochemical parameters, and genetic variants in the INFLACOR (INFlAmmation in Cardiac OpeRations) cohort.In a series of prospectively recruited 518 adult Polish Caucasians who underwent cardiac surgery in which CPB was used, the clinical data, biochemical parameters, IL-6, soluble ICAM-1, TNFa, soluble E-selectin, and 10 single nucleotide polymorphisms were evaluated for their associations with 30-day and 5-year mortality.The 30-day mortality was associated with: pre-operative prothrombin international normalized ratio, intra-operative blood lactate, postoperative serum creatine phosphokinase, and acute kidney injury requiring renal replacement therapy (AKI-RRT) in logistic regression. Factors that determined the 5-year survival included: pre-operative NYHA class, history of peripheral artery disease and severe chronic obstructive pulmonary disease, intra-operative blood transfusion; and postoperative peripheral hypothermia, myocardial infarction, infection, and AKI-RRT in Cox regression. The serum levels of IL-6 and ICAM-1 measured three hours after operation were associated with 30-day and 5-year mortality, respectively. The ICAM1 rs5498 was associated with 30-day and 5-year survival with borderline significance.Different risk factors determined the early (30-day) and late (5-year) survival after adult cardiac surgery in which cardiopulmonary bypass was used. Future genetic association studies in cardiac surgical patients should adjust for the identified chronic and acute postoperative risk factors.


2000 ◽  
Vol 107 (2) ◽  
pp. 197-197 ◽  
Author(s):  
Michael Krawczak ◽  
Stefan Boehringer ◽  
Jörg T. Epplen

2008 ◽  
Vol 9 (1) ◽  
Author(s):  
Veronica Latini ◽  
Gabriella Sole ◽  
Laurent Varesi ◽  
Giuseppe Vona ◽  
Maria Serafina Ristaldi

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