Different Phenotypes in a Family With Androgen Insensitivity Caused by the Same M780I Point Mutation in the Androgen Receptor Gene

This study reported that the same M780I point mutation in the androgen receptor (AR) gene led to different phenotypes within the same family, highlighting variability in androgen insensitivity (AI) syndromes. Among three patients, two exhibited a feminine phenotype indicative of complete AI, while the third was male with partial AI, perineoscrotal hypospadias, and cryptorchidism. Despite having the same mutation, differences in 5 alpha-reductase activity and AR binding capacity were observed, with higher levels in the male patient. The study concluded that the same AR gene mutation can result in varying clinical phenotypes, suggesting that molecular defects alone may not predict AI phenotypes in families.