First Report of Low-Rate Mosaicism for 20q11.21q12 Deletion and Delineation of the Associated Disorder

We describe the first case of mosaic 20q11.2 deletion in a 5-year-old girl affected by mild psychomotor delay, feeding difficulties, growth retardation, craniofacial dysmorphisms, and finger anomalies. SNP array analysis disclosed 20% of cells with a 20q11.21q12 deletion, encompassing the 20q11.2 minimal critical region and the 3 OMIM disease-causing genesGDF5,EPB41L1, andSAMHD1. We propose a pathogenic role of other genes mapping outside the small region of overlap, in particularGHRH (growth hormone releasing hormone), whose haploinsufficiency could be responsible for the prenatal onset of growth retardation which is shared by half of these patients. Our patient highlights the utility of chromosomal microarray analysis to identify low-level mosaicism.Cytogenet Genome Res
Source: Cytogenetic and Genome Research - Category: Genetics & Stem Cells Source Type: research