Comparison of population- and family-based methods for genetic association analysis in the presence of interacting loci
A new paper by Howson et al. explores the power to detect two-locus interactions with different study designs.
Howson JM, Barratt BJ, Todd JA, Cordell HJ. Comparison of population- and family-based methods for genetic association analysis in the presence of interacting loci. Genet Epidemiol. 2005 May 12. [PubMed]
Abstract:
We compared different ascertainment schemes for genetic association analysis: affected sib-pairs (ASPs), case-parent trios, and unrelated cases and controls. We found, with empirical type 1 diabetes data at four known disease loci, that studies based on case-parent trios and on unmatched cases and controls often gave higher odds ratio estimates and stronger significance test values than ASP designs. We used simulations and a simplified disease model involving two interacting loci, one of large effect and one smaller, to examine interaction models that could cause such an effect. The different ascertainment schemes were compared for power to detect an effect when only the locus of smaller effect was genotyped. ASPs showed the greatest power for association testing under most models of interaction except under additive and certain epistatic crossover models, for which case/controls and case-parent trios did better. All ascertainment schemes gave an unbiased estimation of log genotype relative risks (GRRs) under a multiplicative model. Under nonmultiplicative interactions, GRRs at the minor locus as estimated from ASPs could be biased upwards or downwards, resulting in either an increase or decrease in power compared to the case/control or trio design. For the four known type 1 diabetes loci, we observed decreased risks with ASPs, which could be due to additive interactions with the remaining susceptibility loci. Thus, the optimal ascertainment strategy in genetic association studies depends on the unknown underlying multilocus genetic model, and on whether the goal of the study is to detect an effect or to accurately estimate the resulting disease risks. Genet. Epidemiol. (c) 2005 Wiley-Liss, Inc.
4 Comments:
Vous avez un blog très agréable et je l'aime, je vais placer un lien de retour à lui dans un de mon blogs qui égale votre contenu. Il peut prendre quelques jours mais je ferai besure pour poster un nouveau commentaire avec le lien arrière.
Merci pour est un bon blogger.
I look for blogs as great as your work. Fine
blog. I found your site suitable for another visit!
Go and click my home based business insurance blog.
I think this topic is very different and should be more pages like this,Your
comment says a lot of truth,and I'd like to invited you
to visit my page:10/325-
Vicoprofen - Lortab- Tylenol
#3- Ativan
All Major Medications are available right here at: http://www.crdrx.com
Hello
Join for free. Most of 2 millions members.List of most popular hot girls in your area. Find today sex partner here from list of most hot girls in your area. Adult only.
hotgirls xanax sex sexcam phentermine xanax phentermine sex hotbabe sexforadult sex sexygirlsfree sexygirls sexfree adult hotgirlsonline freeadult sexvideo
viagra valium meridia adipex ativan xanax drugs valium tramadol viagra drug store free hosting viagra levitra cialis
Have fun
Post a Comment
<< Home