Exome sequencing in a family with restless legs syndrome

Background:: Restless legs syndrome (RLS) has a high familial aggregation. To date, several loci and genetic risk factors have been identified, but no causative gene mutation has been found. Methods:: We evaluated a German family with autosomal dominantly inherited RLS in 7 definitely and 2 possibly affected members by genome-wide linkage analysis and exome sequencing. Results:: We identified three novel missense and one splice site variant in the PCDHA3, WWC2, ATRN, and FAT2 genes that segregated with RLS in the family. All four exons of the PCDHA3 gene, the most plausible candidate, were sequenced in 64 unrelated RLS cases and 250 controls. This revealed three additional rare missense variants (frequency <1%) of unknown pathogenicity in 2 patients and 1 control. Conclusions:: We present the first next-generation sequencing study on RLS and suggest PCDHA3 as a candidate gene for RLS.