Polycystin-1L3 is a 1,732 amino acid multi-pass membrane protein that contains one PLAT domain, one GPS domain and one C-type lectin domain. Expressed at high levels in placenta and present at lower levels in lung and heart, Polycystin-1L3 is thought to function as an ion-channel regulator that may interact with Polycystin-L and play a role in heteromeric taste channels. The gene encoding Polycystin-1L3 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.