Absence of the testicular determining factor gene SRY in XX true hermaphrodites and presence of this locus in most subjects with gonadal dysgenesis caused by Y aneuploidy

Abstract

OBJECTIVES: The purpose of our study was to discover whether the testicular determining factor gene SAY (sex-determining region on Y) is present or absent in XX true hermaphrodites and in subjects with gonadal dysgenesis caused by Y aneuploidy.STUDY DESIGN: We screened five XX true hermaphrodites and 24 subjects with gonadal dysgenesis caused by Y aneuploidy for the presence or absence of SAY. With the polymerase chain reaction technique, the sequence coding the 80 amino acid-conserved motif was amplified. The 0.9 kb Hincll pY53.3 subclone, which covers the open reading frame of SAY, serves as a probe for Southern blot analysis.RESULTS: Test results for all five XX true hermaphrodites were negative for SAY. Conversely, 22 of the 24 individuals with 45,X/46,XY gonadal dysgenesis were positive for SAY, including the 10 subjects with only bilateral streak gonads.CONCLUSIONS: The absence of SAY in XX true hermaphrodites and the presence of SAY in 10 subjects with 45,X/46,XY constitution who harbored only bilateral streak gonads seem to indicate that multiple genes are involved in gonadal differentiation. (AM J OBSTET GYNECOL 1992;167: 1794-802.)