Familial case of 46,XX male and 46,XX true hermaphrodite associated with a paternal-derived SRY-bearing X chromosome

C R Acad Sci III. 1993;316(4):375-83.


The human testis-determining gene was recently isolated from a 35 kb region on the human Y chromosome which was present in four sex-reversed individuals, three XX males and one true hermaphrodite. One of the XX males and the true hermaphrodite were sibs. A more detailed molecular analysis of these two patients and their family for Y-DNA sequences including the testis-determining gene, SRY was performed. The father was found to harbor two copies of SRY, one on his Y chromosome and the other on his X chromosome located at Xp22 determined by in situ hybridization. Somatic cell hybrids were generated from peripheral blood lymphocytes. Analysis of Y chromosome-negative somatic cell hybrids from the XX male, the true hermaphrodite and their father, revealed that both the X and Y pseudo-autosomal boundaries were present. The present of both boundaries suggests than an unequal interchange of X and Y material occurred with the cross-over breakpoint located within the X pseudo-autosomal region. The paternal SRY-bearing X chromosome was transmitted to two of his children, a 46 XX true hermaphrodite and a 46,XX male. The presence of SRY on an X chromosome associated with two sex phenotypes strongly suggests that the phenotypic variability was caused by differential inactivation of the SRY-bearing X chromosome, thereby influencing SRY expression.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Blotting, Southern
  • Chromosome Inversion*
  • Crossing Over, Genetic
  • Disorders of Sex Development / genetics*
  • Female
  • Gene Expression
  • Humans
  • In Situ Hybridization
  • Male
  • Molecular Sequence Data
  • Pedigree
  • Sex Determination Analysis
  • Sex Differentiation / genetics
  • Testis / growth & development
  • X Chromosome*