RNF166 is a 237 amino acid protein that contains one RING-type zinc finger and a UIM (ubiquitin-interacting motif) repeat. Existing as two alternatively spliced isoforms, RNF166 is encoded by a gene that maps to human chromosome 16q24.3. Chromosome 16 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.