The natural history of familial hypopituitarism.

Familial hypopituitarism in the Hutterite Brethren is an autosomal recessive disorder involving sequential loss of anterior pituitary tropic hormones. Five individuals from two closely related families have been followed for 19 years. Both families are well integrated into the Hutterite community. Three sibs elected not to be treated with growth hormone and sex steroids. These sibs developed growth hormone and gonadotropin deficiency in the first decade of life, with subsequent loss of TSH function and finally ACTH deficiency in the third decade. The pattern of hormone loss differed in the second family, in that deficiency of growth hormone, gonadotropins, and TSH was evident in the first decade. A third family has been reported to have the same disorder and is from a different endogamous subdivision from that of the two families described here. Genealogical analysis of the three families shows that there are four ancestral couples common to the six parents. Thus all affected individuals are likely to be identical by descent for the same ancestral allele. The gene for hypopituitarism is not closely linked to the gene for growth hormone nor to the HLA region.