eRF3a is a 499 amino acid protein that belongs to the GTP-binding elongation factor family and is involved in the regulation of cell growth, specifically via control of translation termination. Human eRF3a shares 94% sequence identity with its mouse counterpart, suggesting a conserved function between species. The gene encoding eRF3a maps to human chromosome 16, which encodes over 900 genes and comprises nearly 3% of the human genome. The GAN gene is located on chromosome 16 and, with mutation, may lead to giant axonal neuropathy, a nervous system disorder characterized by increasing malfunction with growth. The rare disorder Rubinstein-Taybi syndrome is also associated with chromosome 16, as is Crohn's disease, which is a gastrointestinal inflammatory condition.