PDX1 and obesity due to melanocortin 4 receptor deficiency: The best model in differentiating pancreatic cancer cases from controls was the one that included age, sex, education, environmental factors (cigarette smoking, oral hygiene, consumption of vegetables and fruits, allergy, diabetes/glucose intolerance, and BMI), four unlinked SNPs, and the two gene-environment interactions (between poor oral hygiene and NR5A2 rs2816938 and between obesity and PDX1 rs9581943).