ALOPECIA, ANDROGENETIC Alternative titles; symbols BALDNESS, MALE-PATTERNED, INCLUDED; MPB, INCLUDED TEXT Early baldness of the ordinary type has been thought to be autosomal dominant in males and to be autosomal recessive in females who transmit the trait if heterozygous but are bald only if homozygous (Osborn, 1916; Snyder and Yingling, 1935). The transmission through many successive generations, as in the descendants of President John Adams, suggests the operation of a single major gene. It should be possible to map one or more of such genes by linkage methods such as those being used with success in plants and experimental animals androgenic alopecia progesterone topical pattern baldness and with at least promise in connection with complex traits in the human. Hamilton (1951) classified pattern baldness and gave incidence figures. Kuster and Happle (1984) reviewed the genetics of MPB and concluded that the Osborn hypothesis had not been thoroughly tested and was thus of questionable validity. In their analysis of 5 previous studies, Kuster and Happle (1984) concluded that a polygenic mode of inheritance was more likely. Carey et al. (1993) described an autosomal dominant syndrome comprising polycystic ovaries (PCO; 184700) and premature male-patterned baldness. They postulated that polycystic ovary syndrome may be the female phenotype of premature propecia facts progesterone topical pattern baldness male patterned-baldness. In studies of 14 Caucasian families with 81 affected individuals with this PCO/MPB syndrome, Carey et al. (1994) found a single base change in the 5-prime promoter region of the CYP17 gene (202110), which seemed to modify the expression of the syndrome in some families but could be excluded as the primary genetic defect. Ellis et al. (1998) found no evidence that the gene for either of the 2 isoforms of the steroid 5-alpha-reductase enzyme (SRD5A1, 184753; SRD5A2, 607306) is involved in the genetics of MPB. From a population survey of 828 healthy families, they identified 58 young side effects of propecia progesterone topical pattern baldness bald men (aged
