Persistence of mullerian derivatives in males

The persistent mullerian duct syndrome is a rare, autosomal recessive disor der, characterized by the persistence of mullerian duct derivatives-uterus and fallopian tubes-in genetic males otherwise normally virilized. We have collected DNA from 69 families with this syndrome. In 45%, a mutation of th e antimullerian hormone (AMH) gene was detected; 52% were homozygous. The l evel of circulating AMH was extremely low in the great majority of patients , even before puberty, when AMH levels are normally high. Single-strand con formation polymorphism (SSCP)-polymerase chain reaction (PCR) was a very ef fective screening method. In 39% of families, characterized by an AMH level normal for the age of the patient, a mutation of the type II receptor of A MH was detected by automatic sequencing, because SSCP-PCR was not very effe ctive. Forty-eight percent of the mutations were homozygous. A 27-base-pair deletion in exon 10 was noted in 45% of the families. When this very commo n mutation is not taken into account, the proportion of recurrent mutations is 42% for the AMH gene and 33% for the AMH receptor type II gene. In 16% of families, no mutation of either the AMH or the AMH receptor gene was det ectable; this group may correspond to mutations of unknown genes involved i n AMH processing or in downstream AMH transduction. (C) 2000 Wiley-Liss, In c.