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Current Molecular Medicine

Author(s): Tawfiq Froukh* and Ammar Hawwari

DOI: 10.2174/1566524019666190730095630

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Autosomal Recessive Non-syndromic Keratoconus: Homozygous Frameshift Variant in the Candidate Novel Gene GALNT14

Page: [683 - 687] Pages: 5

  • * (Excluding Mailing and Handling)

Abstract

Background: Keratoconus (KC) is usually bilateral, noninflammatory progressive corneal ectasia in which the cornea becomes progressively thin and conical. Despite the strong evidence of genetic contribution in KC, the etiology of KC is not understood in most cases.

Methods: In this study, we used whole-exome sequencing to identify the genetic cause of KC in two sibs in a consanguineous family. The Homozygous frameshift variant NM_001253826.1:c.60delC;p.Leu21Cysfs*6 was identified in the gene Nacetylgalactosaminyltransferase 14 (GALNT14). The variant does not exist in all public databases neither in our internal exome database. Moreover, no database harbours homozygous loss of function variants in the candidate gene.

Result: GALNT14 catalyses the initial reaction in O-linked oligosaccharide biosynthesis, the transfer of an N-acetyl-D- galactosamine residue to a serine or threonine residue on target proteins especially Mucins.

Conclusion: As alterations of mucin’s glycosylation are linked to a number of eye diseases, we demonstrate in this study an association between the truncated protein GALNT14 and KC.

Keywords: NGS, genome, ocular, epithelial, dry-eye, keratoconus.

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