exclusion of identifiable errors, genotyping call rates were 96.9% for 5HTTLPR and 95.4% for rs25531, somewhat lower than normal for our laboratory, but nonetheless much improved over the original assay for 5HTTLPR. In total, 1,232 individuals had been genotyped for the study reported by Gillespie et al. [2005] using the standard protocols available at the time. Of these, 16% had changed genotypes using the new assay. Most inconsistencies (35%) were for samples typed as SS by the earlier assay but SL by the improved assay [expected to be 22% by chance alone: the frequency of SS genotypes reported in Gillespie et al., 2005], consistent with observations of L allele dropout by others [Heils et al., 1996; Kaiser et al., 2002; Yonan et al., 2006].
