Genetically predicted circulating B vitamins in relation to digestive system cancers.

Area of Science:

• Nutritional epidemiology
• Genetic epidemiology
• Gastroenterology

Background:

• Previous research suggests links between folate, vitamin B6, vitamin B12, and digestive cancers.
• The causal relationship requires further investigation.

Purpose of the Study:

• To assess the causal associations between serum concentrations of folate, vitamin B6, and vitamin B12 and digestive system cancers.
• Utilizing a Mendelian randomization approach to infer causality.

Main Methods:

• A two-sample Mendelian randomization study design.
• Used genome-wide significant single nucleotide polymorphisms as genetic instruments for serum vitamin levels.
• Analyzed data from UK Biobank (367,561 individuals) and FinnGen (up to 176,899 participants).

Main Results:

• Genetically predicted folate and vitamin B6 were not associated with digestive system cancers.
• Genetically predicted vitamin B12 showed a positive association with overall digestive system cancer and colorectal cancer in UK Biobank.
• These findings for colorectal cancer were consistent across both UK Biobank and FinnGen cohorts.

Conclusions:

• Elevated serum vitamin B12 concentrations are associated with an increased risk of colorectal cancer.
• No causal link was found between folate or vitamin B6 and digestive system cancers.