Novel mutations of the carbohydrate sulfotransferase-6 (CHST6) gene causing macular corneal dystrophy in India.
OBJECTIVE
Macular corneal dystrophy (MCD) is an autosomal recessive disorder characterized by progressive central haze, confluent punctate opacities and abnormal deposits in the cornea. It is caused by mutations in the carbohydrate sulfotransferase-6 (CHST6) gene, encoding corneal N-acetyl glucosamine-6-O-sulfotransferase (C-GlcNAc-6-ST). We screened the CHST6 gene for mutations in Indian families with MCD, in order to determine the range of pathogenic mutations.


METHODS
Genomic DNA was isolated from peripheral blood leukocytes of patients with MCD and normal controls. The coding regions of the CHST6 gene were amplified using three pairs of primers and amplified products were directly sequenced.


RESULTS
We identified 22 (5 nonsense, 5 frameshift, 2 insertion, and 10 missense) mutations in 36 patients from 31 families with MCD, supporting the conclusion that loss of function of this gene is responsible for this corneal disease. Seventeen of these mutations are novel.


CONCLUSIONS
These data highlight the allelic heterogeneity of macular corneal dystrophy in Indian patients.
Sultana
Afia
A
Kallam Anji Reddy Molecular Genetics Laboratory, Professor Brien Holden Eye Research Centre, Hyderabad 500 034, India.
Sridhar
Mittanamalli S
MS
Jagannathan
Aparna
A
Balasubramanian
Dorairajan
D
Kannabiran
Chitra
C
Klintworth
Gordon K
GK
D000293:Adolescent; D000328:Adult; D000483:Alleles; D003317:Corneal Dystrophies, Hereditary / Q000201:enzymology / Q000453:epidemiology / Q000235:genetics*; D004252:DNA Mutational Analysis; D018740:Genetic Heterogeneity; D006801:Humans; D007194:India / Q000453:epidemiology; D008875:Middle Aged; D009154:Mutation; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D015238:Sulfotransferases / Q000235:genetics*; D000097811:Carbohydrate Sulfotransferases
D015238:Sulfotransferases; D000097811:Carbohydrate Sulfotransferases