persistent mullerian duct syndrome
Definition A rare autosomal recessive form (OMIM:261550) of male pseudohermaphroditism of childhood onset, which is characterised by persistence of mullerian duct (“female”) structures in a phenotypically normal male.
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Clinical findings Cryptorchidism, testicular hypoplasia, normal virilisation at puberty, increased testicular tumours and transverse testicular ectopia.
• Defects of AMH, which encodes anti-mullerian hormone, a hormone that mediates male sexual differentiation. AMH causes regression of mullerian ducts which would otherwise differentiate into the uterus and fallopian tubes, and cause persistent müllerian duct syndrome type I.
• Defects of AMHR2, which encodes the receptor for the anti-mullerian hormone which, with testosterone, results in male sex differentiation, cause persistent mullerian duct syndrome type II.
Synonyms Deficient müllerian* (muellerian, mullerian) inhibitory substance secondary to Sertoli cell defect, familial disorder with presence of fallopian tube—uterus—and testis in a male, familial persistent müllerian duct syndrome, familial uterine hernia syndrome, female genital ducts in an otherwise normal male, hernia uteri inguinale, male internal pseudohermaphroditism, müllerian inhibitor factor deficiency, persistent müllerian duct syndrome types I and II, persistent oviduct syndrome, pseudohermaphroditism—male internal.