DNA was extracted from whole-blood samples obtained from all three affected siblings and both parents. DNA from one affected sibling was used for performing whole-exome sequencing with Illumina’s TruSeq (62 Mb) DNA sample preparation and exome enrichment kits. With the TruSeq exome definition as a reference, coverage was 96% at a read depth of 2×, 87% at a read depth of 10×, and 74% at a read depth of 20×. The mean read depth across the exome was 58×. In total, 22,097 variants were detected.