A large component of this study was previously genotyped at this variant as part of a previous genotyping project19. To complete the genotyping in the sample, we used Sequenom MassArray, homogenous MassEXTEND (hME) or iPLEX assays for genotyping, using Sequenom SpectroTYPER software v3.4 (see Wang et al., 2009)20.