All eight DNA samples revealed the 3‐kb deletion in STX16, located centromeric of GNAS, which is now known to be the most frequent cause of AD‐PHP1B, if located on the maternal allele.(12, 30) Furthermore, analysis of several microsatellite markers across the STX16/GNAS region showed that the investigated affected individuals all share the same haplotype for the chromosome 20q13 region (data not shown). The gene discussed is GNAS; the disease is Alzheimer disease.