An Overview of Genome-Wide Association Study for Genetics Novices: A Review

Hafsa Tahir, Aniqa Ejaz, Tania Mahmood, Sidra Riaz, Rashid Saif


SNP chip-based genome-wide association studies (GWAS) is an inspiring and fast scanning method for mapping variations within the genome and associating them with specific diseases/trait. This association information has enhanced the chances of improvement in disease diagnosis, understanding the causative variants locations and associated gene hunting strategies. GWAS have laid foundation of an era in which both personalized medicine and pharmacogenomics would be reinforced along with better understanding of functional genomics aspects of modern molecular genetics. Since the advent of first GWAS in 2002, thousands of genome wide association studies have been published which have proven GWAS a successful methodology in identifying significant variants in disease/trait association but application of GWAS outcomes to clinical settings demands more evaluation for validity. Here, we have divided the GWAS approach into various aspects including history, development, analysis strategies, approaches, current scenario and different applications with brief description of major methodologies being used in scientific community to get associated SNP hits and narrowing down the search by functional variant filtration involved in subject disease, traits or physiological condition.

Keywords: GWAS, Genetic Association, Linkage Disequilibrium, HapMap, PLINK

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