ENU-induced A to T transversion at base pair 57,301,214 (v38) on chromosome 17, or base pair 22,136 in the GenBank genomic region NC_000083. The mutation corresponds to residue 1,059 in the mRNA sequence NM_011691 within exon 10 of 27 total exons. The mutation results in a threonine to serine substitution at amino acid 321 (R321S) in the VAV1 protein.