A cluster of male pseudohermaphrodites with 5α‐reductase deficiency in Papua New Guinea

We report a cluster of male pseudohermaphrodites from the Simbari Anga linguistic group in the Eastern Highlands of Papua New Guinea. These subjects are born with a rudimentary clitoral‐like penis and pseudovaginal perineoscrotal hypospadias. At puberty, the penis enlarges with concurrent growth of pubic and axillary hair and significant muscular development. There is significant facial hair, but it is less than that of their normal male siblings or other male relatives. Plasma collected from four adult subjects revealed elevated plasma testosterone levels, low to low normal dihydrotestosterone levels, and elevated testosterone/dihydrotestosterone ratios. All subjects had high urinary aetiocholanolone/androsterone ratios, and C₁₂ and C₂₁ 5β/5α metabolite ratios. Decreased 5ot‐reductase activity was demonstrated in fibroblasts cultured from genital skin. The data indicate a phenotypic and biochemical profile similar to patients studied in the Dominican Republic, except tor a greater abundance of facial and body hair. The phenotypic variability, as pertains to facial and body hair, may be related to differences in familial expression, as well as the degree of enzyme deficiency. Infants, thought to be females at birth, were reared as girls until puberty in a society practising one of the strictest gender segregations known. At puberty, these ‘girls’ were discovered to be boys, and a switch of gender roles was instituted. Recently, however, some Muniri, Dunkwi and northern Simbari hamlets recognize these individuals as male in infancy and rear them as boys, calling them ‘kwalatmala’ to distinguish them from normal males, accepting them as an intersex destined to occupy male adult roles.