[A case of male pseudohermaphroditism with structural abnormalities of Y chromosome (ring Y)].

A case of male pseudohermaphroditism with ring Y chromosome is reported. The patient was a 3-year-old boy with hypospadias and right cryptorchidism. Culture of peripheral lymphocytes demonstrated a chromosomal mosaicism of 45 X/46 X, r (Y). Moreover, the chromosomal study with high resolution Q-band method revealed the presence of double ring Y (ring Y and double ring Y with the ratio of 25: 5). A well-developed vagina was discovered by retrograde cystourethrography. Uterus and fallopian tubes were absent at exploratory laparotomy. The gonads existed in the scrotum on the left side and in the inguinal pouch on the right. Both gonads were proved to be testes histologically, but bilateral was deferens were absent and its remnant was found in the retroperitoneal cavity. Plastic surgery for the genital abnormalities was performed. Only 30 cases of ring Y chromosome have been reported in the world including our case and we briefly reviewed these cases.