Mice carrying the mutation are viable, fertile, normal in size and do not display any gross physical or behavioral abnormalities. Screening of third generation mice (G3) on standard chow identified a 11 week old male (born 1/19/2005) with a heart rate of 854 bpm. Repeat testing on week later measured a heart rate of 870 bpm confirming the phenotype. This mutant mouse strain may be useful in studies of tachycardia.
Following multidose ethylnitrosourea (ENU) treatments to induce mutations in male founder C57BL/6J mice (Stock No. 000664), a forward genetic screen was utilized to identify phenotypic deviants in complex heart, lung, blood, and sleep disorders, at the Mouse Heart, Lung, Blood, and Sleep Disorders (HLBS) Center at The Jackson Laboratory. Initial mapping identified the location of the mutation in an interval of 30-35 cM on Chromosome 9.