De novo subtelomeric deletion additional to an inherited apparently balanced reciprocal translocation.

OBJECTIVE

We describe the analysis of an apparently balanced inherited reciprocal translocation in a fetus presenting with multiple congenital abnormalities, characterize the structural chromosome rearrangement, and report an unexpected additional imbalance to the inherited rearrangement.

METHODS

DNA microarray was used to screen for genomic imbalance in subtelomeric and interstitial critical regions. High-resolution comparative genomic hybridization was used to screen for genomic imbalance at a genome-wide level. Fluorescence in situ hybridization using whole-chromosome painting and specific probes was used to characterize the inherited translocation, and the size of the de novoadditional deletion.

RESULTS

An unexpected additional deletion was found in 7qter on derivative 10 of the inherited maternal reciprocal translocation t(7;10)(q11.23; p14).

CONCLUSIONS

We show the usefulness of genome-wide and specific molecular cytogenetic techniques to explore apparently balanced rearrangements.