Assessment of sex chromosome composition using fluorescent in situ hybridization as an adjunct to GTG-banding.

Fluorescent in situ hybridization (FISH) using dual color X chromosome- and Y chromosome-specific probes was employed to assess further the sex chromosome copy number in cells of a phenotypic female patient with hypergonadotropic hypogonadism, primary amenorrhea and growth retardation. The GTG-banding analysis of peripheral blood lymphocytes had revealed the presence of predominantly 46,XY cells. A FISH analysis, undertaken to assess further the contribution of a minor cell line, yielded frequencies of 87% cells with the 46,XY constitution and 9% with the 45,X constitution.