The Problem(s) with GWAS

There is a problem with GWAS, says Mike the Mad Biologist. The "missing heritability" issue — in which identified genetic variation only accounts for a small portion of the estimated genetic variation for a certain trait — has always been a problem. In addition, GWAS also have problems characterizing traits accurately, Mike adds. For example, in studying heart disease, researchers doing GWAS have to be careful to accurately assess traits of interest, since not all heart diseases are alike. But, he real issue, and one that is rarely discussed, is the environmental component of heritability, Mike says, adding, "in fact, to me, the absence of accurate environmental characterization is potentially a huge problem for GWAS." Until researchers characterize the environment more rigorously, they must treat many of the heritability estimates of GWAS as "speculative," he says.