GWAS results available today allow prediction for a large number of common diseases, with accuracies ranging from slight to moderately high, similar to the range of predictive accuracies found in classical prediction (although the specific diseases that can be predicted well differ by method). Indeed, genetic prediction has already been incorporated into clinical practice in situations where relatively rare, but powerful predictors have been discovered, such as HLA-B*701 mediated hypersensitivity reaction to the antiretroviral abacavir (34). In addition, larger meta-analyses and future sequencing studies will identify further risk variants, possibly including lower frequency variants of large effect size. Such studies could bring risk prediction ever closer to the high-accuracy theoretical predictions described above.
