Identification of a novel non-stop mutation in PDE6C gene in an Iranian family with Con-Rod Dystrophy

novel non-stop mutation in PDE6C gene Iranian family with Con-Rod Dystrophy

  • Farideh Ghanbari Mardasi Mail department of midwifery, Shoushtar faculty of medical sciences, shoushtar, Iran
Keywords:
Con-Rod Dystrophy, CORD, PDE6C gene, novel mutation, Next Generation Sequencing, non-stop mutation.

Abstract

Cone-rod dystrophy (CORD) is one of the most common genetic eye disorders. Recent genetic studies have demonstrated that it is a genetically heterogeneous disease among patients.

Molecular genetic analysis of the 22 genes was performed in a family with Cone-rod dystrophy. Bioinformatics was applied for Next Generation Sequencing, and the variants were confirmed by Sanger sequencing. In this study, the non-stop mutation in the PDE6C gene (a normal stop codon is 859th codon of PDE6C located in exon 22 TAA (Stop) --> CAA (Gln) = Stop859Q) leads to a termination-site change and run-on into the 3' untranslated region (UTR) that predicts an extended protein which was found in the family. This mutation has not been described in patients with the CORD phenotype. Also, this is the first study indicating that a non-stop mutation in the homozygous state in PDE6C is responsible for the congenital recessive CORD phenotype.

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Published
2020-08-23
How to Cite
1.
Ghanbari Mardasi F. Identification of a novel non-stop mutation in PDE6C gene in an Iranian family with Con-Rod Dystrophy. Acta Med Iran. 58(6):297-300.
Section
Case Report(s)