More direct tests, comparing genotype frequencies between probands and controls and tracking transmission of the A versus G alleles to affected offspring, did not support the contention that allele status for the HOXA1 A218G polymorphism influences one's susceptibility to autism.
Therefore, although we cannot exclude the possibility that the samples in the two studies are intrinsically different, our data from our sample argue against a major role for HOXA1 (His)73(Arg) in liability to autism.