macular corneal dystrophy

Classification

• type 1:
  • virtual absence of sulfated keratan sulfate in the serum & cornea, as determined by keratan sulfate- specific antibodies
  • homozygous missense mutation in the CHST6 gene
• type 2
  • sulfated keratin sulfate-antibodies in cornea & serum
  • large deletion & replacement in the upstream region of the CHST6 gene

Pathology

• acid mucopolysaccharides are demonstrable in corneal fibroblasts
• synthesis of corneal keratan sulfate and other glycosaminoglycans may be abnormal

Genetics

• autosomal recessive
• associated with mutations in CHST6 Clinical maniifestations:
• onset occurs in the first decade, usually age 5-9
• disorder is progressive
• corneal opacities
• minute, gray, punctate opacities develop
• corneal sensitivity is usually reduced
• painful attacks with photophobia, foreign body sensations, & recurrent erosions occur in most patients

More general terms

• genetic disease of the eye

Additional terms

• carbohydrate sulfotransferase 6
• cornea (C, K)

Database

• OMIM: https://mirror.omim.org/entry/217800