“…It consists of at least 41 different polypeptide subunits (Walker et al, 1992a), seven of which are encoded by the mitochondrial genome and 34 by the nuclear genome. To date only 14 human nuclear complex I genes have been mapped and/or cloned (Duncan et al, 1992;Spencer et al, 1992;Ali et al, 1993;Baens et al, 1993;de Coo et al, 1995de Coo et al, , 1997Hattori et al, 1995;Hyslop et al, 1996;Gu et al, 1996;Zhuchenko et al, 1996;Russel et al, 1997;Procaccio et al, 1997;Dunbar et al, 1997). Dysfunction of the ETC is believed to contribute to many diseases including encephalomyopathies, diabetes, blindness, deafness, and neurodegenerative disorders (Larsson and Clayton, 1995;Parker and Parks, 1995).…”