Objective: To evaluate the independent and joint effects of FADS1 polymorphism and fish oil intake on oral squamous cell carcinoma( OSCC).
Methods: A case-control study was conducted with 259 newly diagnosed primary OSCC patients and538 controls frequency-matched by sex and age in Fujian from September 2010 to September 2014. Data on demographics and dietary habits such as marine fish oil intake were collected using a structure questionnaire. FADS1 rs174549 genotype was determined using Taq Man genotyping assays. Unconditional logistic regression was used to the oddsratios( ORs) and their 95% confidence intervals( CI) of FADS1 polymorphism and fish oil intake for OSCC.
Results: FADS1 rs174549 AA genotype was associated with decreased risk of OSCC( codominant model: OR = 0. 53, 95% CI 0. 33-0. 85; recessive model: OR = 0. 57, 95% CI 0. 38-0. 87). Compared with those who non-intake marine fish oil, regularly intake of marine fish oil decreased the risk of OSCC( OR = 0. 54, 95%CI: 0. 32-0. 91). Moreover, a multiplicative interaction between FADS1 rs174549 polymorphism and marine fish oil intake for oral cancer( OR_(multiplicative)= 0. 31, 95% CI0. 11-0. 87).
Conclusion: FADS1 rs174549 polymorphism and marine fish oil intake may be independent protective factors for OSCC with a gene-diet multiplicative interaction.
Keywords: fatty acid desaturase 1; marine fish oil; oral squamous cell carcinoma; polymorphism.