Clinical Information (ข้อมูลทางคลินิก):
Apolipoprotein E (ApoE) is located on 19q13.2 and consists of 299 amino acids in length. It plays an important role in cholesterol transportation and metabolism. The three most common alleles of ApoE are e3 (Cys112/Arg158), e2 (Cys112/Cys158), and e4 (Arg112/Arg158). Among these three alleles, e3 is the wild-type and most commonly found. Mutations in ApoE might increase or decrease the risk of Alzheimer’s disease. Individuals with the APOE e3/e4 genotype have a three-to-four-fold relative risk, while individuals with the APOE e4/e4 genotype have a 15-fold relative risk compared to those with the APOE e3/e3 genotype. Other than the risk of late-onset Alzheimer's developing, these mutations are related to the age of onset of the disease. The average age of developing late-onset Alzheimer is 68 years at 94% for homozygous E4, 76 years at 47% frequency for heterozygous E4, and 84 years at 20% frequency for those who do not carry E4. Moreover, mutations in ApoE might increase or decrease the risk of cardiovascular disease.
Clinical Reference (เอกสารอ้างอิง):
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