rs9923231

rs9923231 is a single nucleotide polymorphism (SNP) in the MTHFR gene, identified by the reference SNP ID rs9923231 in the dbSNP database. It is a common genetic variant that has been studied in the context of folate metabolism and one-carbon metabolism.

The MTHFR gene encodes methylenetetrahydrofolate reductase, an enzyme that participates in processing folate within the one-carbon cycle. The precise functional effect of rs9923231 can vary among individuals and studies; some evidence suggests it may influence gene expression or enzyme activity depending on the allele, while other work finds minimal or no direct impact on function.

Population data indicate that the minor allele of rs9923231 occurs at varying frequencies across ethnic groups. It is commonly observed in many populations and often studied together with other MTHFR variants in haplotype analyses related to homocysteine regulation and folate status.

Clinical associations examined for rs9923231 include plasma homocysteine concentrations, folate status, and a range of health outcomes such as cardiovascular disease risk, neural tube defect risk, pregnancy outcomes, and cancer susceptibility. However results have been inconsistent, with small effect sizes and considerable influence from nutrition, lifestyle, and interactions with other genetic factors. As a result, routine clinical testing for rs9923231 alone is not universally recommended for disease prediction or management.

Genetic testing often includes rs9923231 in SNP arrays or nutrigenetic panels. Interpretation typically requires considering overall folate intake, vitamin B12 status, and other variants in the MTHFR gene. Further research continues to clarify its precise role and clinical utility.