NADH Dehydrogenase Ubiquinone 1 Beta Subcomplex 9 (NDUFb9)

Gu et al. (1996) used a set of cosmids that map to 8q13.3, the region involved in that syndrome. Cosmids were used as genomic clones to isolate corresponding cDNAs. One cDNA clone was found to have 89% sequence similarity to the B22 subunit of bovine NADH-ubiquinone oxidoreductase, a mitochondrial protein in the respiratory electron transport chain. The human cDNA encodes a 179-amino acid polypeptide sharing 90.5% similarity with the bovine sequence. Because other mitochondrial enzyme mutations have been implicated in hearing loss syndromes, Gu et al. (1996) suggested that this is a strong candidate for involvement in BOR.Lin et al. (1999) described the genomic structure of the NDUFB9 gene, including the nucleotide sequence, organization, and boundaries of the 4 coding exons.