As prerequisite for exploring the contribution of normal variation in genes of the broader fragile X gene family (FMR1, FXR1, FXR2, FMR2) to the overall continuum of autism‐related phenotypes, we had to determine the polymorphic repeat lengths in FMR1 and FMR2 in the schizophrenic discovery and the healthy control sample to exclude mutations. Here, FMR1 is linked to autism.