Figure 3. Sequence chromatograms and segregation analysis of the p.S205X GRK1 variant. A: Sequence chromatogram of part of exon 1. Sequence of normal control sample (left panel) and an affected individual IV-1 (right panel) with the homozygous mutant sequence c.614C>A. B: StuI restriction analysis of the 552 bp PCR products of exon 1 in all family members. Fragments were resolved on an 1.5% agarose gel. Individuals with a single fragment of 552 bp were identified as homozygous normal since they did not contain the restriction site for StuI. Those with three fragments (552 bp, 366 bp, and 186 bp) were heterozygous carriers of the mutation, and those with two fragments (366 bp and 186 bp) carried the mutation homozygously.