Inactivating mutations in MFSD2A, required for omega-3 fatty acid transport in brain, cause a lethal microcephaly syndrome

Nat Genet. 2015 Jul;47(7):809-13. doi: 10.1038/ng.3311. Epub 2015 May 25.


Docosahexanoic acid (DHA) is the most abundant omega-3 fatty acid in brain, and, although it is considered essential, deficiency has not been linked to disease. Despite the large mass of DHA in phospholipids, the brain does not synthesize it. DHA is imported across the blood-brain barrier (BBB) through the major facilitator superfamily domain-containing 2a (MFSD2A) protein. MFSD2A transports DHA as well as other fatty acids in the form of lysophosphatidylcholine (LPC). We identify two families displaying MFSD2A mutations in conserved residues. Affected individuals exhibited a lethal microcephaly syndrome linked to inadequate uptake of LPC lipids. The MFSD2A mutations impaired transport activity in a cell-based assay. Moreover, when expressed in mfsd2aa-morphant zebrafish, mutants failed to rescue microcephaly, BBB breakdown and lethality. Our results establish a link between transport of DHA and LPCs by MFSD2A and human brain growth and function, presenting the first evidence of monogenic disease related to transport of DHA in humans.

Publication types

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

MeSH terms

  • Adolescent
  • Animals
  • Biological Transport
  • Blood-Brain Barrier / metabolism
  • Brain / metabolism*
  • Case-Control Studies
  • Child
  • Child, Preschool
  • Consanguinity
  • Fatty Acids, Omega-3 / metabolism*
  • Female
  • Genes, Lethal
  • Genetic Association Studies
  • HEK293 Cells
  • Humans
  • Infant
  • Male
  • Mice, Knockout
  • Microcephaly / genetics*
  • Mutation, Missense
  • Symporters
  • Syndrome
  • Tumor Suppressor Proteins / genetics*
  • Zebrafish


  • Fatty Acids, Omega-3
  • MFSD2A protein, human
  • Symporters
  • Tumor Suppressor Proteins

Associated data

  • dbGaP/PHS000288.V1.P1