Investigation of germline VHL variants in Iranian patients with retinal capillary hemangioblastoma and genotype-phenotype analysis

Ophthalmic Genet. 2023 Jun;44(3):211-217. doi: 10.1080/13816810.2022.2138455. Epub 2023 Jan 30.

Abstract

Background: Retinal capillary hemangioblastoma (RCH), while sporadic in some cases, is the most common and earliest manifestation of von Hippel-Lindau disease (VHL). This is the first report on different types of VHL variants and genotype-phenotype correlations in Iranian families with RCH.

Materials and methods: In this prospective observational case series study, 17 families with RCH were included. PCR was performed to amplify 3 exons of VHL gene. Afterward, Sanger sequencing was performed on all PCR products. For the detection of VHL copy number variations, MLPA was used.

Results: Our study identified 10 different types of VHL variants. Missense mutations were the most common variants found and affected the structure of α domain of the VHL protein (pVHL). The majority of mutations (72.7%) in the patients with RCH and central nervous system hemangioblastoma (CNS-HB) were located on α domain.

Conclusion: α domain of VHL may play a potential role in the pathogenesis of RCH. Our findings suggest that genotype-phenotype characteristics in those variants in α- domain may predispose patients to RCH with CNS-HB.

Keywords: Iranian patients; RCH; VHL.

Publication types

  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • DNA Copy Number Variations
  • Genotype
  • Germ Cells / pathology
  • Germ-Line Mutation
  • Hemangioblastoma* / genetics
  • Hemangioblastoma* / pathology
  • Humans
  • Iran / epidemiology
  • Phenotype
  • Retinal Neoplasms* / pathology
  • Von Hippel-Lindau Tumor Suppressor Protein / genetics
  • von Hippel-Lindau Disease* / complications
  • von Hippel-Lindau Disease* / genetics

Substances

  • Von Hippel-Lindau Tumor Suppressor Protein
  • VHL protein, human