Ocular manifestations among patients with congenital insensitivity to pain due to variants in PRDM12 and SCN9A genes

Am J Med Genet A. 2022 Dec;188(12):3463-3468. doi: 10.1002/ajmg.a.62968. Epub 2022 Sep 16.

Abstract

Congenital insensitivity to pain (CIP) is a group of rare genetic disorders with a common characteristic of absent sensation to nociceptive pain. Here we present a series of six patients; three had a novel variant in the PRDM12 gene (group A), and three had a missense variant in the SCN9A gene (group B). We compared the ocular manifestations between the two groups. Records of these patients from 2009 through 2018 were reviewed. The retrieved data included demographics, genetic analysis results, ocular history and ophthalmic findings including visual acuity, corneal sensitivity, tear production, ocular surface findings, cycloplegic refraction, and fundoscopy. We found that patients with PRDM12 variant had more severe manifestations of ocular surface disease, with more prevalent corneal opacities and worse visual acuity, compared to patients with SCN9A variant.

Keywords: CIP; PRDM12; SCN9A; congenital insensitivity to pain; dry eye syndrome; neurotrophic keratopathy.

MeSH terms

  • Carrier Proteins* / genetics
  • Corneal Opacity*
  • Humans
  • NAV1.7 Voltage-Gated Sodium Channel* / genetics
  • Nerve Tissue Proteins* / genetics
  • Pain
  • Pain Insensitivity, Congenital* / genetics

Substances

  • Carrier Proteins
  • NAV1.7 Voltage-Gated Sodium Channel
  • Nerve Tissue Proteins
  • Prdm12 protein, human
  • SCN9A protein, human