Among these 20 associated regions, we identified a new CNVR 11q11 associated with early-onset (extreme) obesity. While the presence of copy number variability at CNVR 11q11 is well established (28–30), its relationship to obesity has not been described before. CNVR 11q11 covers the three protein coding genes OR4P4, OR4S2, OR4C6 (according to RefSeq of UCSC hg18; http://genome.ucsc.edu/) of the OLR family 4. OLRs interact with odorant molecules in the nose, to initiate a neuronal response that triggers the perception of a smell. They form the largest mammalian protein superfamily. There is a high percentage (∼55%) of human pseudogenes (29). The OLR proteins are members of the family of G-protein-coupled receptors arising from single-coding exon genes.
