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.