A simple but important observation is that GWA analysis provides a highly effective approach for exploring the genetic underpinnings of common familial diseases. Our yield of novel, highly significant association findings is comparable to, or exceeds, the number of those hitherto-generated by candidate gene or positional cloning efforts. For many of the compelling signals, replication has already been obtained, including regions on chromosomes 3p21, 5q33, 10q24 and 18p11 for CD23, 12q13, 12q24, 16p13 and 18p11 in T1D10 and 6p22 and 16q12 in T2D19-22,24. For others, replication is required to establish a definitive relationship with disease. Additional findings of particular interest include the identification of several loci that seem to influence susceptibility to multiple autoimmune diseases, and the suggestion of a novel locus for RA which shows sex-specific effects.
