Alzheimer’s disease is a degenerative brain disorder that affects millions of people worldwide.

While the exact cause of Alzheimer’s is still not fully understood, research has shown that genetics play a significant role in determining a person’s risk of developing the disease. Certain genetic factors have been identified that may increase an individual’s susceptibility to Alzheimer’s. In this article, we will explore eight of these genetic factors and their impact on Alzheimer’s risk.

1. ApoE Gene

The ApoE gene, specifically the ε4 variant, is considered the most significant genetic risk factor for late-onset Alzheimer’s disease.

Individuals who inherit one copy of the ApoE ε4 allele from one parent have an increased risk of developing Alzheimer’s compared to those who do not carry this variant. Furthermore, the risk escalates for individuals who carry two copies of the ε4 allele.

2. Presenilin 1 (PSEN1)

Mutations in the Presenilin 1 (PSEN1) gene are responsible for early-onset familial Alzheimer’s disease. This gene provides instructions for producing a protein that is involved in the processing of certain proteins within the brain.

Mutations in PSEN1 can lead to the overproduction of beta-amyloid, a protein fragment that forms the characteristic plaques found in the brains of Alzheimer’s patients.

3. Presenilin 2 (PSEN2)

Similar to PSEN1, mutations in the Presenilin 2 (PSEN2) gene are also associated with early-onset familial Alzheimer’s disease.

PSEN2 mutations lead to the same cascade of events seen in PSEN1 mutations, resulting in the accumulation of beta-amyloid plaques and the development of Alzheimer’s symptoms.

4. Amyloid Precursor Protein (APP)

Mutations in the Amyloid Precursor Protein (APP) gene can cause rare forms of early-onset familial Alzheimer’s disease. The APP gene provides instructions for making a protein that is cleaved into smaller fragments, including beta-amyloid.

Mutations in APP can increase the production of beta-amyloid, leading to the formation of plaques in the brain.

5. Clusterin (CLU)

Genetic variations in the Clusterin (CLU) gene have been associated with an increased risk of sporadic late-onset Alzheimer’s disease.

CLU codes for a protein involved in various biological processes, including the regulation of tissue inflammation and clearance of beta-amyloid. Some variations in the CLU gene have been found to impair these functions, contributing to the development of Alzheimer’s.

6. Triggering Receptor Expressed on Myeloid Cells 2 (TREM2)

Mutations in the Triggering Receptor Expressed on Myeloid Cells 2 (TREM2) gene have been implicated in an increased risk of Alzheimer’s disease. TREM2 is involved in the immune response and the clearance of cellular debris in the brain.

Mutations in TREM2 can impair these functions, leading to an accumulation of damaging proteins, such as beta-amyloid, in the brain.

7. ATP-Binding Cassette Subfamily A Member 7 (ABCA7)

Genetic variants in the ATP-Binding Cassette Subfamily A Member 7 (ABCA7) gene have been linked to an elevated risk of late-onset Alzheimer’s disease.

ABCA7 is involved in the transportation of lipids, such as cholesterol, which play a crucial role in brain cell function. Mutations in ABCA7 can disrupt lipid transportation and metabolism, potentially contributing to the development of Alzheimer’s.

8. SORL1

Variations in the SORL1 gene have been associated with an increased risk of late-onset Alzheimer’s disease. The SORL1 gene is involved in the regulation of the production and trafficking of amyloid precursor protein (APP).

Mutations or variants in SORL1 can disrupt this process, leading to an increased accumulation of beta-amyloid and the progression of Alzheimer’s pathology.