Abstract
The missing heritability problem refers to the gap between heritability estimates for complex human traits based on quantitative genetics and the small magnitude and unreliability of contemporary molecular genetics, especially genome wide association studies. The author reviews the origins of the missing heritability problem and considers research that has attempted to resolve it by quantifying the joint explanatory power of multiple genetic loci, rather than considering their effects one at a time. Although this program has made an important contribution to understanding the role of genetics in the development of complex behaviors, it does not resolve the missing heritability problem.