Scnm1^s

The A variant (T on negative gene strand) of SNP rs13474321 in this putative splice factor gene has been identified in the sequence of the C57BL/6J, C57BL/6NJ and most other C57 strains and closely related C58 strains. All other tested strains have the non-deleterious G variant. The resulting premature stop codon at arginine 187 (p.R187*) removes the C-terminal 43 amino acids. This substitution also destroys a predicted exon splice enhancer region and results in a unique transcript that lacks exon 6. Thus, mice are predicted to produce two abnormal proteins, one that is prematurely truncated at residue 186 and a smaller 164 residue protein. The R187* mutation influences the amount of correct splicing of Scn8a transcript in medJ mice which directly correlates to the severity of the disease. (J:84898)