The phenotypic deviant was identified by by hindlimb wasting, gait abnormalities, and shakiness following multidose ethylnitrosourea (ENU) treatments. Sequence analysis indicates that this recessive mutation is a nucleotide substitution resulting in the replacement of serine at codon 330 with proline (S330P, c.T988C; transcript Nadk2-205) in exon 11. The mutation is near the C-terminal end of the catalytic domain and results in a 65.6 +/- 10% reduction of NADK2 protein expression. (J:332444)