A Common Variant in the MC1R Gene (p.V92M) is associated with Alzheimer's Disease Risk

Area of Science:

• Neurogenetics
• Alzheimer's Disease Research
• Human Genetics

Background:

• The genetic underpinnings of late-onset Alzheimer's disease (LOAD) remain incompletely understood, with known risk genes explaining only a portion of the genetic variance.
• APOE gene variants are significant contributors to LOAD risk, but a substantial portion of genetic susceptibility is yet to be identified.

Purpose of the Study:

• To investigate the potential role of the Melanocortin 1 Receptor (MC1R) gene in the genetic etiology of LOAD.
• To identify novel genetic factors contributing to Alzheimer's disease susceptibility.

Main Methods:

• Sequencing of the MC1R gene in a cohort of 525 Spanish LOAD patients and 160 healthy controls.
• Statistical analysis to assess the association between MC1R variants and LOAD risk, including stratification by APOE genotype and cerebrospinal fluid (CSF) AD profile.

Main Results:

• A common MC1R variant, p.V92M (rs2228479), was found to be significantly associated with an increased risk of developing LOAD (OR: 1.99).
• The association was more pronounced in LOAD patients without APOE risk factors and those with a typical AD CSF profile.
• No association was observed between the MC1R p.V92M variant and the age of onset for Alzheimer's disease.

Conclusions:

• The MC1R gene, specifically the p.V92M variant, represents a potential novel genetic risk factor for late-onset Alzheimer's disease.
• Further research is warranted to elucidate the functional mechanisms of MC1R in brain cells and its pathways in the context of AD pathogenesis.