This family consists of several Caenorhabditis elegans specific ly-6-related HOT and ODR proteins. These proteins are involved in the olfactory system. Odr-2 mutants are known to be defective in the ability to chemotax to odorants that are recognised by the two AWC olfactory neurons. Odr-2 encodes a membrane-associated protein related to the Ly-6 superfamily of GPI-linked signaling proteins [1].

1: The Caenorhabditis elegans odr-2 gene encodes a novel Ly-6-related protein required for olfaction. Chou JH, Bargmann CI, Sengupta P; Genetics 2001;157:211-224. PMID:11139503