• taste receptor
• SNP
• gene
• colorectal
• cancer

ABSTRACT
Taste receptors are encoded by highly polymorphic gene families. In the past years, several evidences have shown that they are not only involved in the perception of taste. TASs genes were found to be expressed in other organs such as the colon, stomach, pancreas, brain, lung and testis in which they perform different functions. Multiple epidemiological and molecular evidences have highlighted the role of genetic polymorphisms and in particular of single nucleotide polymorphisms (SNPs) in receptor function. Apart from taste perception SNPs in these genes are also associated with other phenotypes such as diabetes, alcohol consumption, nicotine addiction, and BMI others. Some of these parameters appear among the risk factors for colorectal cancer (CRC). In Europe, the sporadic form of CRC is the second for both incidence and mortality. For CRC multiple risk factors have been identified, among them genetics, lifestyles habits such as cigarette smoking, alcohol drinking, consumption of red meat and some predisposing conditions such as chronic inflammation, Crohn's disease and ulcerative colitis. The first aim of this study was to find a possible association between polymorphisms of the TAS2R16 gene and CRC development and as second aim to detect a possible association between CRC risk factors and polymorphisms. The TAS2R16 gene binds with salicin, a molecule similar to aspirin that is used in the treatment of inflammatory diseases. In order to perform a case-control study we selected and genotyped 6 polymorphisms of TAS2R16 in 3882 individuals from 4 different European countries (Czech Republic, Lithuania, Italy and Spain). Statistical analysis did not show a direct association between polymorphisms and CRC risk, the signal closest to the significance threshold of P<0.05 was observed for rs1525489 with a p-value of 0.084. Regarding diabetes, we have found an association for the same polymorphism associated with CRC risk (rs1525489). However the diabetogenic allele is associated with decreased CRC risk suggesting that if the SNP has a role in CRC it is T2D independent. We analyzed also the association between TAS2R16 SNPs and alcohol consumption, observing a statistically significant association for the C allele of rs860170 and the allele G of rs1357949 and increased alcohol consumption. Finally, we also observed a positive correlation between the G allele of rs10268496 and BMI. In conclusion, our data suggest that polymorphisms of the TAS2R16 gene do not have a direct correlation between with susceptibility to CRC. However, we propose here some potentially interesting associations between the gene variants and life style habits.