In a total of 40 individuals from 20 cases (25 samples from 11 cases of phenotypic females including 3 Turner's syndrome, and 15 samples from 9 cases of phenotypic males) under the informed consent, which was presumed as sex differentiation anomaly by clinical and cytogenetic findings, peripheral blood, cord blood, skin, gonad, buccal cells, born marrow, amniotic fluid and placental chorionic villi were examined by FISH, Southern blot hybridization, PCR, PCR-RFLP, PCR-SSCP, PCR-CFLP and direct DNA sequencing for X (3 loci) and Y chromosomes (27 loci), DAZ, DAZLA which we previously identified on chromosome 3p25. Marker chromosomes were demonstrated that 2 cases were derived from X and 7 were derived from Y by using G, Q banding and FISH. Among the samples analyzed, a total of 15 cases including of these 7 cases from Y, 3 cases of 45,X/46,XY, 2 cases of gonadoblastoma (XX, XY), 2 cases of ambiguous external genitalia (XX, XY) and 1 case of small Y, a case of ovotestis with 46,XX (periph
eral blood and both right and left gonads), and XX male with hypospadias and cryptorchild testis (peripheral blood) were found any Y contents. A case of monozygotic twins of discordant sex both with 47,X,idic(Yp)x2/45,X/46,X,idic(Yp) mosaicism was demonstrated to lack from Yq11.2 to Yq terminal. A case of dizygotic twins of discordant sex was revealed to be blood chimerism. In 2 cases of 46,X,+mar, the markers were demonstrated derived from a Y chromosome including p terminal to q11.23 and paracentric inversion in the remained Y long arm, and I(Y)(p10) individually. Five cases of phenotypic female with 46,X,+mar, mosaicism of 45,X cell line were found in several tissue including gonads. No deletion and mutation were demonstrated in SRY positive cases. Available evidence suggests that the DAZLA gene is a participant in human oogenesis (Mol. Hum. Reprod., 1999). Furthermore, we designated loss of sex chromosome (aneuploidy) accumulate genetic mutation,
The present report illustrates that "sex determination" and "sex differentiation" are depend upon SRY gene expression in relation to tissue limited mosaicism, and the importance of other gene, especially in X chromosome.