Characterization of a de novo unbalanced Y;autosome translocation in a 45,X mentally retarded male and literature review

Objective: To describe the molecular and cytogenetic characterization of a de novo unbalanced Y;autosome translocation in a 45,X mentally retarded male. Design: Descriptive case study and literature review. Setting: Tertiary medical center. Patient(s): A 17-year-old 45,X mentally retarded male with no stigmata of Turner syndrome. Intervention(s): Molecular and cytogenetic investigations, physical examination, and hormonal assays. Main Outcome Measure(s): Cytogenetic analysis, fluorescence in situ hybridization (FISH), array comparative genomic hybridization (CGH), and polymorphic DNA marker analysis. Result(s): The FISH showed a Y/18p translocation. Array CGH revealed a loss of distal chromosome 18p material and a loss of part of Yq material corresponding to deletions of chromosomal segments of 18pter→18p11.2 and Yq11.221→Yqter. Polymorphic DNA markers analysis showed that the X chromosome was of maternal origin and the deletion of 18p was of paternal origin. Conclusion(s): This study confirms the usefulness of array CGH in the detection of subtle chromosomal rearrangements resulting in an unbalanced Y;autosome translocation.