Mutations in LOXHD1, an evolutionarily conserved stereociliary protein, disrupt hair cell function in mice and cause progressive hearing loss in humans

Am J Hum Genet. 2009 Sep;85(3):328-37. doi: 10.1016/j.ajhg.2009.07.017.


Hearing loss is the most common form of sensory impairment in humans and is frequently progressive in nature. Here we link a previously uncharacterized gene to hearing impairment in mice and humans. We show that hearing loss in the ethylnitrosourea (ENU)-induced samba mouse line is caused by a mutation in Loxhd1. LOXHD1 consists entirely of PLAT (polycystin/lipoxygenase/alpha-toxin) domains and is expressed along the membrane of mature hair cell stereocilia. Stereociliary development is unaffected in samba mice, but hair cell function is perturbed and hair cells eventually degenerate. Based on the studies in mice, we screened DNA from human families segregating deafness and identified a mutation in LOXHD1, which causes DFNB77, a progressive form of autosomal-recessive nonsyndromic hearing loss (ARNSHL). LOXHD1, MYO3a, and PJVK are the only human genes to date linked to progressive ARNSHL. These three genes are required for hair cell function, suggesting that age-dependent hair cell failure is a common mechanism for progressive ARNSHL.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Carrier Proteins / chemistry
  • Carrier Proteins / genetics*
  • Cilia / pathology
  • Cilia / ultrastructure
  • Codon, Terminator / genetics
  • Conserved Sequence*
  • DNA Mutational Analysis
  • Evolution, Molecular*
  • Genes, Recessive
  • Hair Cells, Auditory, Outer / pathology*
  • Hair Cells, Auditory, Outer / ultrastructure
  • Hearing Loss / genetics*
  • Hearing Loss / pathology
  • Heterogeneous-Nuclear Ribonucleoproteins / genetics
  • Humans
  • In Situ Hybridization
  • Mice
  • Molecular Sequence Data
  • Mutation / genetics*
  • Mutation, Missense / genetics
  • Nerve Degeneration / genetics
  • Nerve Degeneration / pathology
  • Protein Structure, Secondary
  • Spiral Ganglion / pathology
  • Spiral Ganglion / ultrastructure


  • Carrier Proteins
  • Codon, Terminator
  • Heterogeneous-Nuclear Ribonucleoproteins
  • LOXHD1 protein, human
  • LOXHD1 protein, mouse