Single nucleotide polymorphisms in PIK3CG, TSC1/2, which is mutated in the autism spectrum disorder tuberous sclerosis (TS), and INPP1, inositol polyphosphate-1-phosphatase, were shown to be in linkage disequilibrium in patients with autism (Serajee et al., 2003). This evidence concerns the gene INPP1 and tuberous sclerosis.