Allele-specific, multiplex PCR has been developed for APOE genotyping, with common and specific inner primers for polymorphism detection at codons 112 and 158. The agarose electrophoresis pattern can show the homozygous and heterozygous genotypes of E2, E3, and E4 alleles.186 Various kits have been designed for APOE PCR genotyping. One of the most frequently used kits is the LightCycler® ApoE Mutation Kit by Roche Diagnostics (Basel, Switzerland).187 PCR-RFLP is a widely used, simple and fast method for APOE genotyping. The genomic DNA should be amplified with specific primers, followed by HhaI digestion. The samples can be separated in 8% polyacrylamide (PAGE) gel, and visualized with fluorescent dye.188
