ENU-induced A to G transition at base pair 84,588,753 (v38) on chromosome 8, or base pair 250,124 in the GenBank genomic region NC_000074 encoding Cacna1a. The mutation corresponds to residue 4,897 in the mRNA sequence NM_007578 within exon 30 of 47 total exons and residue 4,756 in the mRNA sequence NM_001252059 within exon 29 of 46 total exons. The mutation results in a tyrosine to cysteine substitution at position 1,539 (Y1539C) in variants 1, 3, and 4 CACNA1A protein and a Y1492C substitution in variant 2 of the CACNA1A protein.