Figure 1. Pedigree analysis and molecular study of Family 1. A: DNA sequencing revealed heterozygous missense mutation in the codon 244 VSX1 in which A→G (arrow indicates the position of nucleotide substitution). B: Amplification refractory mutation system (ARMS) for H244R VSX1 genotyping showing the co-segregation of the H244R VSX1 mutation among family members including two KTCN patients (III:1 and II:6) as well as in two individuals without KTCN clinical features (III:2 and II:5). PCR products of the internal control primer pair (383 bp), PCR product of the wild-type (WT) and mutant primer pairs (236 bp) are indicated. M, 50-bp ladder is present. C: The pedigree of Family 1 show four affected patients (arrow indicates the proband) and segregation of p.H244R through the family. Each individual was reported by age (in years), genotype and topography images. Filled symbols represent KTCN patient and open symbols reveal individuals without clinical KTCN.