The Branch mutation is an A-to-T transversion at base pair 46,560,651 (v38) on chromosome 18, or base pair 13,978 in the GenBank genomic region NC_000084 encoding TICAM2. The mutation, which is within the third and last exon, corresponds to residue 844 in the mRNA sequence NM_173394 and results in an aspartic acid (D) to valine (V) substitution at amino acid position 123 (D123V) of the protein. (J:215010)