Genomics of Loa loa, a Wolbachia-free filarial parasite of humans

Nat Genet. 2013 May;45(5):495-500. doi: 10.1038/ng.2585. Epub 2013 Mar 24.


Loa loa, the African eyeworm, is a major filarial pathogen of humans. Unlike most filariae, L. loa does not contain the obligate intracellular Wolbachia endosymbiont. We describe the 91.4-Mb genome of L. loa and that of the related filarial parasite Wuchereria bancrofti and predict 14,907 L. loa genes on the basis of microfilarial RNA sequencing. By comparing these genomes to that of another filarial parasite, Brugia malayi, and to those of several other nematodes, we demonstrate synteny among filariae but not with nonparasitic nematodes. The L. loa genome encodes many immunologically relevant genes, as well as protein kinases targeted by drugs currently approved for use in humans. Despite lacking Wolbachia, L. loa shows no new metabolic synthesis or transport capabilities compared to other filariae. These results suggest that the role of Wolbachia in filarial biology is more subtle than previously thought and reveal marked differences between parasitic and nonparasitic nematodes.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, N.I.H., Intramural

MeSH terms

  • Animals
  • Brugia malayi / genetics
  • Filariasis / genetics*
  • Filariasis / parasitology
  • Filarioidea / genetics*
  • Filarioidea / parasitology
  • Genes, Helminth / genetics*
  • Genome, Helminth*
  • Humans
  • Loa / genetics*
  • Molecular Sequence Data
  • Phylogeny
  • Protein Kinases / metabolism*
  • Symbiosis
  • Wolbachia / genetics*
  • Wuchereria bancrofti / genetics


  • Protein Kinases

Associated data

  • GENBANK/ADBU02000000
  • GENBANK/ADBV01000000
  • GENBANK/ADBW01000000
  • GENBANK/ADHD00000000
  • GENBANK/ADHE00000000