Mendelian Randomization Studies on Actinic Keratosis.

Area of Science:

• Genetics
• Dermatology
• Epidemiology

Background:

• Actinic keratosis (AK) is a common sun-induced skin condition and a precursor to squamous cell carcinoma.
• Epidemiological studies on AK risk factors are often limited by confounding.
• Mendelian randomization (MR) offers a method to infer causality using genetic variants.

Purpose of the Study:

• To review published Mendelian randomization (MR) studies on actinic keratosis (AK).
• To examine AK as both an exposure and an outcome in MR analyses.
• To identify current applications and future directions for MR in AK research.

Main Methods:

• Systematic literature search of MEDLINE and Embase databases.
• Inclusion of original human research employing MR for AK-related associations.
• Focus on two-sample MR using summary-level genome-wide association data.

Main Results:

• Eight MR studies were included, primarily using European population data.
• Studies investigated various exposures (metabolic, immune, dermatological, sun sensitivity) related to AK.
• One study explored AK as an exposure for skin cancer risk; no meta-analysis was possible due to study heterogeneity.

Conclusions:

• The body of MR research on AK is currently small but methodologically varied.
• This review summarizes the application of MR in AK research.
• Findings can inform future MR investigations into AK etiology and prevention.