Persistent müllerian duct syndrome in a man with transverse testicular ectopia.

A 33-year-old Pakistani man with transverse testicular ectopia underwent surgery for repair of a left inguinal hernia. At operation a uterine structure with attached vasa deferentia was found in the left inguinal area and it was removed. Transverse testicular ectopia has been reported previously in association with the persistent müllerian duct syndrome. A deficiency of activity of a müllerian inhibiting substance during gestation is believed to be responsible for this syndrome. Most patients usually are sterile. Cloning of the gene for a müllerian inhibiting substance should permit studies of the pathogenesis of the persistent müllerian duct syndrome.