Two rare PROX1 variants in patients with lymphedema

Mol Genet Genomic Med. 2020 Oct;8(10):e1424. doi: 10.1002/mgg3.1424. Epub 2020 Aug 5.

Abstract

Background: The PROX1 gene is specifically expressed in a subpopulation of endothelial cells that, by budding and sprouting, give rise to the lymphatic system. It also plays a critical role in neurogenesis and during development of many organs, such as the eye lens, liver, and pancreas.

Methods: We used next-generation sequencing (NGS) to sequence the DNA of a cohort of 246 Italian patients with lymphatic malformations. We first investigated 29 known disease-causing genes: 235 of 246 patients tested negative and were then retested for a group of candidate genes, including PROX1, selected from a database of mouse models. The aim of the study was to define these patients' genotypes and explore the role of the candidate gene PROX1 in lymphedema.

Results: Two of 235 probands were found to carry rare heterozygous missense variants in PROX1. In silico analysis of these variants-p.(Leu590His) and p.(Gly106Asp)-indicates that the overall protein structure was altered by changes in interactions between nearby residues, leading to functional protein defects.

Conclusions: Our results suggest that PROX1 is a new candidate gene for predisposition to lymphedema.

Keywords: PROX1; genetic diagnosis; lymphedema; next-generation sequencing (NGS).

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Female
  • Heterozygote
  • Homeodomain Proteins / chemistry
  • Homeodomain Proteins / genetics*
  • Humans
  • Lymphedema / genetics*
  • Lymphedema / pathology
  • Male
  • Mutation, Missense
  • Pedigree
  • Phenotype
  • Protein Domains
  • Tumor Suppressor Proteins / chemistry
  • Tumor Suppressor Proteins / genetics*

Substances

  • Homeodomain Proteins
  • Tumor Suppressor Proteins
  • prospero-related homeobox 1 protein