MGI:1096879Homozygotes for a targeted null mutation exhibit early post-implantation lethality, in the absence of intramitochondrial iron accumulation. Conditional knockouts, specific to striated muscle and neuron/striated muscle, show cardiac hypertrophy and large sensory neuron dysfunction, respectively. Homozygosity for the p.G127V mutation leads to increased pre-weaning mortality and affects cell cycles and mitochondrial morphology and physiology.