Prevalence of granular corneal dystrophy type 2-related p.R124H variant in a South Korean population.

Purpose: Granular corneal dystrophy type 2 (GCD2) is an autosomal dominant disorder and is associated with the arginine to histidine substitution at codon 124 (p.R124H) of the gene. Although p.R124H is known to be the most common corneal dystrophy-related pathogenic variant, there are few data on the frequency of this variant in the South Korean population.

Methods: In total, 2,060 anonymous DNA samples from a public umbilical cord blood bank were tested for the p.R124H variant using real-time PCR.

Results: Six of the 2,060 samples [0.29%; 95% confidence interval (CI), 0.12-0.67%] were heterozygous for the p.R124H variant. The prevalence of the GCD2-related p.R124H variant in this population was estimated to be 291.3 per 100,000 [95% confidence interval (CI), 118.5-667.0].

Conclusions: To our knowledge, this is the largest study that has estimated the prevalence of the GCD2-related p.R124H variant in South Korea.