Crypt Y chromosome fragment resulting from an X;Y translocation in a patient with premature ovarian failure.

Objective: To identify a cryptic Y chromosome fragment that resulted from a X;Y translocation in a patient with premature ovarian failure (POF) and analyze the karyotype-phenotype correlation.

Design: Case report.

Setting: A university-based reproductive medicine center.

Patient(s): A 33-year-old woman with POF.

Intervention(s): Karyotyping analysis, comparative genomic hybridization, fluorescence in situ hybridization, and polymerase chain reaction (PCR) analysis for the patient.

Main Outcome Measure(s): Karyotype determination of the patient.

Result(s): The patient was suspected to carry an abnormal X chromosome by traditional cytogenetic analysis. A Y chromosome hybridization signal was found in the patient's genome by comparative genomic hybridization analysis. The fluorescence in situ hybridization result showed that the Y chromosome material resulted from a translocation between Xq and Yq. Using the specific sequence-tagged sites, the breakpoints on the X and Y chromosomes were located at Xq26.3 and Yq11.223, respectively. Combined with chromosome G banding and C banding, the karyotype of the patient was determined as 46,X,der(X)t(X;Y) (q26.3;q11.223).

Conclusion(s): The advanced molecular cytogenetic techniques are helpful to detect cryptic chromosome aberrancies in patients with POF. This rare case supports that Xq26-q28 is the critical region of POF, and is helpful to analyze the risk of gonadoblastoma in patients with POF with Y chromosomal material.