X-linked Ndufa1 (NADH dehydrogenase (ubiquinone) 1 alpha subcomplex, 1) encodes an essential component of the respiratory chain Complex 1, which is involved in the transfer of electrons from NADH to ubiquinone. Complex 1 is controlled by 58 genes, of which two are X-chromosome-linked and 7 are mitochondrial. Deficiencies in Complex 1 are the most common cause of mitochondrial disease, and alterations in the X-chromosome genes are associated with sex-dependent variation in mitochondrial disease. 
The Ndufa1S55A knock-in mice carry an S55A amino acid substitution in exon 2 and are a model for systemic partial Complex I deficiency. Hemizygous males exhibit age-dependent Purkinje cell degeneration, reduced heme levels, glucose intolerance, reduced respiratory exchange ratio (hypometabolic), reduced body heat, hypoactivity and decreased food intake (although body weight is similar or higher than controls). Lifespan in hemizygous males is reduced as compared to control males, however, lifespan in homozygous females is slightly increased. Homozygous females exhibit abnormal mammary gland ductal architecture (personal communication). This strain may be useful for studying sex-dependent variation in mitochondrial disease.
Mice on the BALB/c genetic background are distributed as MMRRC Stock No. <a href="https://www.jax.org/strain/031807">043917</a>. The phenotype on the BALB/c genetic background has not yet been assessed (March 2018).

Ndufa1S55A knock-in mice carry an S55A amino acid substitution in the X-linked (NADH dehydrogenase (ubiquinone) 1 alpha subcomplex, 1) gene. Males hemizygous for the mutation exhibit multiple features of systemic partial Complex I deficiency. This strain may be useful for studying sex-dependent variation in mitochondrial disease.

This strain is hosted by NIH's MMRRC, which partners with JAX for the distribution of this and other strains. For additional information and to purchase, please visit the MMRRC site.