T to A transversion at base pair 77,948,299 (v38) on chromosome 18, or base pair 9,892 in the GenBank genomic region NC_000084. The mutation corresponds to residue 243 (c.243T>A) in the mRNA sequence NM_001195633.2 within exon 2 of 44 total exons. The mutation results in substitution of cysteine 70 for a premature stop codon (p.C70*) in the EPG5 protein. (J:272115)