Periventricular nodular heterotopia and Williams syndrome

Abstract

We report here on the first case of a child with bilateral periventricular nodular heterotopia (PNH) and Williams syndrome. Fluorescent in situ hybridization (FISH) analyses demonstrated a deletion of the elastin gene in the Williams syndrome critical region (WSCR). Further mapping by loss of heterozygosity analysis both by microsatellite marker and SNP profiling demonstrated a 1.5 Mb deletion beyond the telomeric end of the typical WSCR. No mutations were identified in the X‐linked filamin‐A gene (the most common cause of PNH). These findings suggest another dominant PNH disorder along chromosome 7q11.23.