Partial androgen insensitivity syndrome with R840H mutation in androgen receptor: report of one case.

Androgen insensitivity syndrome (AIS) is the major cause of male pseudohermaphroditism. The severity of the disorders varies widely, ranging from the phenotypic women with female external genitalia in cases of complete AIS to the phenotype of ambiguous genitalia in partial androgen insensitivity syndrome (PAIS) and a rare group of phenotypic normal males with azoospermia. Here, we report an infant of PAIS with a missense mutation at position 2881 (G-->A) in exon 7, encoding substitution of histidine for arginine at codon 840 of the androgen receptor (AR) gene. Both the biochemical and molecular studies are presented. Establishing the diagnosis of PAIS is very important for gender assignment to an infant of ambiguous genitalia. The molecular analysis will facilitate genetic counselling to the maternal side relatives for carrier detection and prenatal diagnosis.