Familial gynecomastia without hypogonadism.

A family, six members of which had gynecomastia without hypogonadism, is presented. Endocrine studies failed to show the specific nature of breast enlargement in the patients. Chromosomal studies using peripheral leukocytes resulted in normal findings. In one of the patients, chromosomal studies were done using breast tissue and fascia, and again no abnormalities could be detected. The mode of inheritance may be autosoma dominant with sex limitations; however, X-linked inheritance cannot be ruled out.