COMMENTARY Genetic Scoring Analysis: a way forward in Genome Wide Association Studies?

For the past 5 years genome-wide association studies (GWAS) have dominated the search for new genes for complex diseases overtaking other approaches of gene finding such as candidate gene and linkage analyses. Facilitated by technological developments in molecular biology, genetic epidemiologists have so far discovered many variants associated with several common diseases and traits such as Type 2 Diabetes, age-related macular degeneration and Crohn’s disease [1]. There currently are 26 established susceptibility genes published for type 2 diabetes [2], 54 for human height and 22 for lipid levels [3, 4]. These variants still explain only a small part of the genetic variance or heritability, for human height and lipids up to 4–6 % [5, 6], and subsequently the search for novel variants continues to unravel ‘missing heritability’