Clinical and molecular characterization of a patient with 15q21.2q22.2 deletion syndrome

We report on a 16-year-old girl with a complex phenotype, including intellectual disability, facial dysmorphisms, and obesity. During her infancy, she presented with weak sucking, global developmental delay, and later with excessive eating with central obesity. The girl was clinically diagnosed with probable Prader-Willi syndrome. Chromosomal analysis showed a de novo deletion 46,XX,del(15)(q21q22). However, the use of the Affymetrix CytoScan HD Array defined the exact breakpoints of the deleted 15q21q22 region. The imbalance, about 10.5 Mb in size, is to date the second largest deletion ever described in this chromosomal region. In addition, our patient carries a microdeletion in the 1q44 region and a gain in 9p24. The array result was arr[hg19] 9p24.1(6,619,823-6,749,335)×3, 1q44(248,688,586-248,795,277)×1, 15q21.2 q22.2(50,848,301-61,298,006)×1. Although our patient presents additional chromosomal alterations, we provide a correlation between the clinical findings and the phenotype of the 15q21 deletion syndrome.