A large family in which the Aarskog syndrome is transmitted in three generations was studied. In affected males, a large variability of expression was observed, while females show minor signs only. However it is sometimes possible to identify individual females as carriers. The observation of male to male transmission and the absence of symptoms in some daughters of affected male persons suggest a sex-influenced autosomal inheritance in this family. This may suggest heterogeneity in the Aarskog syndrome, since in most families described an X-linked recessive mode of inheritance was indicated.