MECP2 and Williams syndrome: The MQF-PCR method achieved 100% sensitivity and 100% specificity in the detection of patients with the Williams-Beuren syndrome, Velocardiofacial syndrome, Lubs syndrome (MECP2 duplication) and the 17q11.2 microduplication involving the gene NF1. We believe that our method can be expanded to any syndrome originating from loss or gain or genomic material.