Three New Mutations and Mild, Asymmetrical Phenotype in the Highly Distinctive LAMM Syndrome: A Report of Eight Further Cases

Genes (Basel). 2019 Jul 12;10(7):529. doi: 10.3390/genes10070529.

Abstract

Labyrinthine aplasia, microtia, and microdontia (LAMM) is an autosomal recessive condition causing profound congenital deafness, complete absence of inner ear structures (usually Michel's aplasia), microtia (usually type 1) and microdontia. To date, several families have been described with this condition and a number of mutations has been reported. We report on eight further cases of LAMM syndrome including three novel mutations, c. 173T>C p.L58P; c. 284G>A p.(Arg95Gln) and c.325_327delinsA p.(Glu109Thrfs*18). Congenital deafness was the primary presenting feature in all affected individuals and consanguinity in all but two families. We compare the features in our patients to those previously reported in LAMM, and describe a milder, asymmetrical phenotype associated with FGF3 mutations.

Keywords: FGF3; LAMM syndrome; and microdontia; congenital deafness; external ear abnormalities; labyrinthine aplasia; microtia.

Publication types

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

MeSH terms

  • Adult
  • Child, Preschool
  • Congenital Microtia / genetics*
  • Congenital Microtia / pathology*
  • Consanguinity
  • DNA Mutational Analysis
  • Deafness / congenital
  • Ear, Inner / abnormalities*
  • Ear, Inner / pathology
  • Female
  • Fibroblast Growth Factor 3 / genetics*
  • Hearing Loss, Sensorineural / genetics*
  • Hearing Loss, Sensorineural / pathology*
  • Humans
  • Infant
  • Infant, Newborn
  • Male
  • Mutation
  • Phenotype
  • Tooth Abnormalities / genetics*
  • Tooth Abnormalities / pathology*

Substances

  • FGF3 protein, human
  • Fibroblast Growth Factor 3

Supplementary concepts

  • Deafness, Congenital, with Inner Ear Agenesis, Microtia, and Microdontia