Identification of Potentially Pathogenic Variants in the Posterior Polymorphous Corneal Dystrophy 1 Locus

PLoS One. 2016 Jun 29;11(6):e0158467. doi: 10.1371/journal.pone.0158467. eCollection 2016.

Abstract

Posterior polymorphous corneal dystrophy 1 (PPCD1) is a genetic disorder that affects corneal endothelial cell function and leads to loss of visual acuity. PPCD1 has been linked to a locus on chromosome 20 in multiple families; however, Sanger sequencing of protein-coding genes in the consensus region failed to identify any causative missense mutations. In this study, custom capture probes were utilized for targeted next-generation sequencing of the linked region in a previously reported family with PPCD1. Variants were detected through two bioinformatics pipelines and filtered according to multiple criteria. Additionally, a high-resolution microarray was used to detect copy number variations. No non-synonymous variants in the protein-coding region of annotated genes were identified. However, 12 single nucleotide variants in 10 genes, and 9 indels in 7 genes met the filtering criteria and were considered candidate variants for PPCD1. Eleven single nucleotide variants were confirmed by Sanger sequencing, including 2 synonymous variants and 9 non-coding variants, in 9 genes. One microdeletion was detected in an intron of OVOL2 by microarray but was subsequently not identified by PCR. Using a comprehensive next-generation sequencing approach, a total of 16 genes containing single nucleotide variants or indels that segregated with the affected phenotype in an affected family previously mapped to the PPCD1 locus were identified. Screening of these candidate genes in other families previously mapped to the PPCD1 locus will likely result in the identification of the genetic basis of PPCD1.

MeSH terms

  • Algorithms
  • Computational Biology
  • Corneal Dystrophies, Hereditary / genetics*
  • DNA Copy Number Variations
  • Family Health
  • Female
  • High-Throughput Nucleotide Sequencing
  • Humans
  • Male
  • Microfilament Proteins / genetics
  • Microtubule-Associated Proteins / genetics
  • Mutation, Missense
  • Polymorphism, Single Nucleotide*
  • Promoter Regions, Genetic
  • Thrombomodulin / genetics
  • Transcription Factors / genetics

Substances

  • CCM2L protein, human
  • Microfilament Proteins
  • Microtubule-Associated Proteins
  • Ovol2 protein, human
  • THBD protein, human
  • Thrombomodulin
  • Transcription Factors

Supplementary concepts

  • Corneal Dystrophy, Posterior Polymorphous, 1