Focal facial dermal dysplasia type 4: identification of novel CYP26C1 mutations in unrelated patients

J Hum Genet. 2018 Mar;63(3):257-261. doi: 10.1038/s10038-017-0375-x. Epub 2017 Dec 20.

Abstract

The focal facial dermal dysplasias (FFDDs) are a group of rare inherited developmental disorders characterized by congenital scar-like atrophic lesions in the bitemporal (FFDD1, 2, and 3) or preauricular (FFDD4) areas. FFDD4 is an autosomal-recessive trait characterized by preauricular skin defects without additional dysmorphic findings. Previously, only two CYP26C1 mutations in four unrelated patients with FFDD4 were reported. Here, we report two additional unrelated FFDD4 patients with four CYP26C1 mutations including three novel lesions: a missense mutation, c.230G>C (p.Arg77Pro), and two splice-site mutations, c.1191+1G>T (IVS5(+1)G>T) and c.1191+2insT (IVS5(+2)insT). In silico analyses predicted all three mutations as pathogenic. Compound heterozygosity was validated through parental studies. These results provide further evidence that CYP26C1 mutations are the molecular genetic basis of FFDD4. Identification of additional cases by dermatologists, pediatricians, and medical geneticists will lead to further understanding of the clinical spectrum of FFDD4 and define its molecular genetic heterogeneity.

Publication types

  • Case Reports

MeSH terms

  • Alleles
  • Amino Acid Substitution
  • Cytochrome P450 Family 26 / genetics*
  • DNA Mutational Analysis
  • Ectodermal Dysplasia / diagnosis*
  • Ectodermal Dysplasia / genetics*
  • Focal Facial Dermal Dysplasias
  • Genetic Association Studies*
  • Heterozygote
  • Humans
  • Infant
  • Male
  • Mutation*
  • Phenotype*

Substances

  • CYP26C1 protein, human
  • Cytochrome P450 Family 26