A 10.7 Mb interstitial deletion of 13q21 without phenotypic effect defines a further non-pathogenic euchromatic variant.

Abstract

Chromosome 13 deletions are associated with widely varying phenotypes but the clinical picture nearly almost includes mental and growth retardation, craniofacial dysmorphisms, and/or malformations. Several attempts have been made to link monosomy 13q intervals with specific clinical features, but a genotype-phenotype correlation could not be delineated. We report on a woman with a normal phenotype and intelligence referred for chromosomal analysis because of recurrent abortions followed by reproductive loss. Conventional karyotyping revealed an interstitial deletion of chromosome 13q21. By SNP array analysis and FISH the deletion was shown to comprise nearly 10.7 Mb of euchromatic material. This region harbors several genes but an association with recurrent miscarriages has not yet been reported. This is the second report of a 13q21 deletion without psychomotoric retardation, dysmorphisms and malformations. Both cases indicate that this 13q21 deletion can be added to the growing list of euchromatic imbalances without obvious phenotypic abnormalities.