Isolated hypogonadotrophic hypogonadism: a family with autosomal dominant inheritance

A family is reported in which isolated hypogonadotrophic hypogonadism is inherited as an autosomal dominant condition with variable expression. In previous familial cases, inheritance was autosomal recessive. Comparison is made with the endocrine and genetic findings in Kallmann's syndrome, which should be considered a separate disorder. There is difficulty in drawing a sharp distinction between hypogonadotrophic hypogonadism and constitutional delay in puberty in this family.