0467.cC
海量文库 文档专家
当前位置:首页 >> >>

复旦大学医学遗传学课件casecontrolTDT分析_图文

Fudan Genetic Workshop 2005 Genetic Epidemiology in Populations Genetic Association Studies: Studies with Unrelated Individuals Yin Yao yyao@jhsph.edu Fudan Genetic Workshop, Jan 04 2005 ? Assessing risk for disease due to specific alleles/genotypes – Contrast direct / indirect genetic association studies – Discuss genetic models – Tests and estimates of association between alleles/genotypes and disease – Designs to be used Learning Objectives for This Lecture ? Applications for genetic association analyses ? Direct versus indirect association ? Indirect association: marker-based disease association – Exploits LD between markers and unobserved disease variants ? Examples of direct and indirect association studies ? Study designs for direct and marker-based (LD) association Genetic Association Studies in Epidemiology Applications: ? Fine mapping ? Candidate gene effects ? Whole genome scan ? Gene – environment effects ? Drug response modification Genetic Association Studies in Epidemiology Common Designs: ? Cross-sectional ? Case-control ? Cohort ? Clinical Trial (drug response hypothesis is really a case-control) ? Case-family (trios, sibs, extended families) ? Case-only Learning Objectives for This Lecture ? Applications for association analyses ? Direct versus indirect association ? Indirect association: marker-based association – Exploits LD ? Examples of direct and indirect association studies ? Study designs for direct and marker-based (LD) association Genetic epidemiology studies – two different concepts 1. Direct method – Testing whether a particular allele is a disease predisposing (causative) allele – ‘exposure status’ directly measured Eg: A particular APOE allele (e4) changes protein isoform APOE gene on c19 ..GACTAAGGCCC CCGTTCAAGGAA.. C/T ? Genotype that particular site for association study Genetic epidemiology studies – two different concepts 2. ‘LD Mapping’ (indirect method) – ‘exposure status’ not directly measured – Rely on markers correlated with true exposure status ? This correlation is due to linkage disequilibrium Eg: Genotype a nearby genetic marker among study participants APOE gene on c19 ..GACTAAGGCCC CCGTTCAAG…GA CCTG.. C/T A/G Rely on correlation (LD) between these alleles to detect association! Direct Tests ? Test for association between observed genotypes and disease outcome …CCCCCG … …CCCCCG … …CCCCCG … …CCTCCG … …CCTCCG … …CCTCCG … CC CT TT Total Case a c e nd Control b d f nh Total m1 m2 m3 N ? D

网站首页 | 网站地图
All rights reserved Powered by 0467资源网 0467.cc
copyright ©right 2014-2019。
文档资料库内容来自网络,如有侵犯请联系客服。liunxqq@126.com