Genetic counseling in a patient with XXY/XXXY/XY mosaic Klinefelter's syndrome: estimate of sex chromosome aberrations in sperm before intracytoplasmic sperm injection.

OBJECTIVE

To report the sex chromosome aberrations in the sperm of a patient with mosaic Klinefelter's syndrome before ICSI.

DESIGN

Case report.

SETTING

Institute of Human Genetics, University Hospital

PATIENT(S): A patient with an XXY/XXXY/XY mosaic Klinefelter's syndrome and extreme oligozoospermia.

INTERVENTION(S): Skin biopsy, buccal smear, hair root sampling, and semen sampling.

MAIN OUTCOME MEASURE(S): The karyotypes of three additional somatic cell systems and the ratio of sex chromosome aberrations in sperm.

RESULT(S): After two-color fluorescence in situ hybridization of 202 interphase sperm nuclei, both the proportion of hyperhaploid 24, XY and 25, XXY sperm (5.0% and 0.5%, respectively) and of hyperhaploid 24, XX sperm (2.0%) were elevated. In contrast with peripheral lymphocytes, 93.9% of which showed sex chromosome aberrations, in the present patient only 7.5% of sperm proved to be hyperhaploid with an extra sex chromosome.

CONCLUSION(S): The determination of sex chromosome aberrations in the sperm of a patient with mosaic Klinefelter's syndrome may provide additional information to estimate the transmission risk to his offspring.