APOE Alzheimer’s Genetics: How rs429358 and rs7412 Make Up Your Risk

APOE Alzheimer’s genetics are shaped by rs429358 and rs7412. Learn how these variants form the APOE ε2, ε3, and ε4 alleles and how they influence Alzheimer’s disease risk.

APOE Alzheimer’s Genetics: How rs429358 and rs7412 Shape Risk

APOE Alzheimer’s genetics are primarily determined by two key SNPs: rs429358 and rs7412. Combinations of these variants define the common APOE alleles ε2, ε3, and ε4, which influence susceptibility to late-onset Alzheimer’s disease [R, R].

You can analyze your APOE genotypes instantly at GeneExplorer for free.

How APOE Alzheimer’s Genetics Work

The APOE gene has three common protein isoforms [R, R]:

• ε2

• ε3, the most common

• ε4, associated with increased risk of late-onset Alzheimer’s disease

These common APOE isoforms are primarily determined by two SNPs: rs429358 and rs7412.

1. rs429358

The C allele at rs429358 is required for the common ε4 haplotype. However, this SNP cannot determine a person’s APOE genotype by itself; rs7412 must also be considered.

2. rs7412

The T allele at rs7412 contributes to the ε2 haplotype when it occurs on the same chromosome as the T allele at rs429358.

Using forward-strand alleles, the three common APOE haplotypes are:

• ε2: rs429358 T + rs7412 T

• ε3: rs429358 T + rs7412 C

• ε4: rs429358 C + rs7412 C

Because each person inherits two copies of APOE, the combined genotypes are commonly interpreted as follows:

• rs429358 TT + rs7412 TT = ε2/ε2

• rs429358 TT + rs7412 CT = ε2/ε3

• rs429358 TT + rs7412 CC = ε3/ε3

• rs429358 CT + rs7412 CC = ε3/ε4

• rs429358 CC + rs7412 CC = ε4/ε4

• rs429358 CT + rs7412 CT = usually ε2/ε4

The last combination is phase-ambiguous in unphased raw DNA data. Although ε2/ε4 is generally the expected interpretation, the rare ε1/ε3 configuration is theoretically possible.

APOE ε4 increases susceptibility to late-onset Alzheimer’s disease, but it does not determine whether someone will develop the disease. APOE ε2 is generally associated with lower risk relative to ε3.

What Each APOE Allele Means for Alzheimer’s

ε2 (Associated with lower risk)

• Associated with reduced late-onset Alzheimer’s disease risk relative to ε3

• Does not guarantee protection

• Defined by rs429358 T and rs7412 T on the same chromosome

NIA describes ε2 as potentially protective or associated with lower risk, not as absolute protection [R].

ε3 (Typical risk)

• Commonly used as the reference allele in Alzheimer’s risk studies

  
  

• The most common APOE allele

• Defined by rs429358 T and rs7412 C on the same chromosome

ε4 (Higher risk)

• Strongest common genetic risk factor for late-onset Alzheimer’s disease

• Associated with altered amyloid processing, inflammatory responses, lipid metabolism, and other Alzheimer’s-related pathways

• Defined by rs429358 C and rs7412 C on the same chromosome.

Risk tiers:

• ε3/ε4 → generally associated with increased risk relative to ε3/ε3

• ε4/ε4 → highest-risk common APOE genotype

• Note: lifestyle, vascular health, and other genes still matter greatly.

How We Calculate Your APOE Alzheimer’s Genetics

GenesUnveiled uses:

• rs429358 and rs7412

• Verified forward-strand allele orientation

• APOE allele and genotype reconstruction

This provides a research-based APOE interpretation from compatible raw genotype data. Learn more about what raw DNA data is, and how to analyze it. Raw consumer DNA data is not a clinical diagnosis. Results may be affected by missing calls, strand orientation, genotyping errors, or phasing ambiguity and should be confirmed by an appropriately accredited clinical laboratory before medical decisions are made.