Abstract
Purpose: :
To report a case of macular corneal dystrophy associated with compound heterozygous mutations (one known and one previously unknown) in the carbohydrate sulfotransferase 6 gene (CHST6).
Methods: :
Genomic DNA was obtained from the proband with written informed consent and was subjected to polymerase chain reaction-mediated amplification of CHST6. The amplification products were directly sequenced.
Results: :
A 76-year-old man visited our corneal clinic with a main complaint of gradual impairment of vision. Slitlamp examination revealed diffuse opacity in the surface-to-deep portion of the central corneal stroma and white nodules in the deep portion of the peripheral stroma in both eyes of the patient. Histological analysis showed the accumulation of acid mucopolysaccharide in the surface-to-deep region of the stroma of both corneas. Molecular genetic analysis revealed that the patient harbored both a novel CCG → CGG (Pro → Arg) heterozygous mutation at codon 186 and a known GAG → AAG (Glu → Lys) heterozygous mutation at codon 274 of CHST6. We performed penetrating keratoplasty on the right eye of the patient.
Conclusions: :
As far as we are aware, this is the first report of a P186R mutation of CHST6 in a patient with macular corneal dystrophy. The compound heterozygous P186R and E274K mutations of CHST6 are likely responsible for the macular corneal dystrophy of the proband.
Keywords: cornea: clinical science • genetics • degenerations/dystrophies