Unilateral gonadal dysgenesis with both testis and fallopian tube on the same side in a 45,X/46,X inv (Y) mosaic male.

A 5-year-old male with ambiguous external genitalia, hypospadias and microphallus without an urethral orifice was referred for cytogenetic studies. Exploratory laparotomy revealed presence of an infantile uterus and unilateral gonadal dysgenesis with both testes and fallopian tube on the right side. The metaphase cells from peripheral blood culture showed both 45,X/46,X inverted Y (p11.2q11.23) cell-lines (98:2). The inverted Y was found to be of paternal origin. Maternal chromosomal pattern was normal 46,XX. The presence of a fallopian tube next to testis suggest absence of secretion of anti-Mullerian hormone by Sertoli cells. The absence of Wolffian duct derivatives suggest insufficient secretion of testosterone by Leydig cells.