Otopetrin 3 (OTOP3)

Otoconia are biominerals within the utricle and saccule of the inner ear that are critical for the perception of gravity and linear acceleration. The classic mouse mutant 'tilted' (tlt) and the allelic mouse mutant 'mergulhador' (mlh) are recessive mutations that affect balance by impairing otoconial morphogenesis without causing collateral deafness.

By database searching with the OTOP1 sequence as query, Hurle et al. (2003) identified 2 OTOP1-like genes, OTOP2 and OTOP3, in mouse and human. By genomic sequence analysis, they mapped both mouse genes to chromosome 11q21 and both human genes to a region of syntenic homology on chromosome 17q25.3.