A to G transition at base pair 46,308,439 (v38) on chromosome 19, or base pair 4,120 in the GenBank genomic region NC_000085. The mutation corresponds to residue 1,256 in the mRNA sequence NM_019408 (variant 1) within exon 10 of 22 total exons. The mutation results in an aspartic acid to glycine substitution at position 316 (D316G) in all isoforms of the NF-B2 protein.