Caenorhabditis elegans (Nematode, N2) (WBcel235)

Caenorhabditis elegans (Nematode, N2) Assembly and Gene Annotation

NOTE: The genome sequence and annotation for C. elegans are updated in Ensembl infrequently. The data here corresponds with WormBase WS282. For the latest genome and annotation, please visit WormBase ParaSite (for an Ensembl-oriented view), or WormBase.

About Caenorhabditis elegans

The nematode worm Caenorhabditis elegans has been a major model organism for basic biomedical research for over 30 years. Genetic and molecular research in C.elegans has played a key role in the development of our understanding of many important processes, including cell death, microRNAs and RNA interference, development, and aging. C. elegans was the first animal whose genome was sequenced (C. elegans Sequencing Consortium, 1998), and has been an exemplar in the application of genomic data to functional biology in animals.

C. elegans is a small, free-living nematode found in decaying plant material, especially compost and mushroom beds in temperate regions throughout the world. It feeds on the bacteria and other microorganisms associated with plant decay, and is frequently found associated with snails, slugs, millipedes, mites and pill bugs, which are presumed to transport worms from one location to another. The animal has a short generation time, developing through four larval stages into an adult. C. elegans is hermaphroditic and distinct from the majority of other characterised nematodes which have both male and female adult animals.

Picture credit: Bob Goldstein, UNC Chapel Hill Creative Commons Attribution 3.0 via Wikimedia Commons (Image source)


C. elegans was the first multicellular organism to be sequenced, in a collaboration between the The Genome Institute at Washington University and The Wellcome Trust Sanger Institute. An essentially complete C. elegans sequence was published in Science in December 1998, and although the last remaining gap in the sequence was closed in October 2002, the genome sequence and annotation continue to be actively curated by WormBase. The assembly here is WBcel235, which corresponds with WormBase WS279.


The canonical gene set for C. elegans is actively curated by WormBase. The annotation represented corresponds with WormBase WS279.


  1. Genome sequence of the nematode C. elegans: a platform for investigating biology.
    C. elegans Sequencing Consortium. 1998. Science. 282:2012-2018.



AssemblyWBcel235, INSDC Assembly GCA_000002985.3, Dec 2012
Database version111.282
Golden Path Length100,286,401
Genebuild byWormBase
Genebuild methodImport
Data sourceWormBase

Gene counts

Coding genes19,985
Non coding genes24,813
Small non coding genes24,519
Long non coding genes294
Gene transcripts60,000