Fig. 2.
Structure of the APOE gene with four exons (top). Non-synonymous mutations at codon 112 (Cys112Arg) and codon 158 (Arg158Cys) in exon 4 code for three common alleles/haplotypes: APOE*2, APOE*3, and APOE*4 (bottom right), resulting in six genotypes (bottom left). The most common APOE*3 allele has Cys at position 112 and Arg at position 158 in the ApoE protein. The amino acid change in APOE*4 at codon 112 is indicated by Arg*, and the amino acid change in APOE*2 at codon 158 is indicated by Cys*