The Determination of IL-6 rs1800795 Polymorphism Distribution in Turkish National Cross-Country Skiing Athletes Sub-groups Created Referring to the 1km CCSTAs

Abstract

Objective: Interleukin-6 (IL-6) is an effective and functional protein with a cytokine structure. IL-6 produces a pro/anti-inflammatory response in the immune system and muscle tissue hypertrophy and repair. We aimed to investigate the IL-6 rs1800795 polymorphism in athletes who were members of the Turkish national cross-country skiing team in order to determine the advantageous genotype for endurance performance. Methods: A total of 34 athletes within three groups-general (group-1), female (group-2), and male (group-3)-were enrolled in the study. Each group was also divided into two sub-groups as faster and slower referring to their 1-kilometer cross-country skiing time averages (1km CCSTAs). Blood samples were used for DNA isolation, and genotyping was completed by real-time PCR. Chi-square Fisher's and descriptive tests were used for statistical analysis. Results: The groups' 1km CCSTAs were 188.7 +/- 22.4, 212.3 +/- 17.8, and 177.4 +/- 14.1 seconds, respectively. We detected the genotypes as follows: 17 GG (50%) and 17 GC (50%) in Group 1, 5 GG (45%) and 6 GC (55%) in Group 2, and 12 GG (52%) and 11 GC (48%) in Group 3. We detected no CC genotype in the groups. Conclusion: Although the GC genotype ratio was higher in the faster athletes of each group compared to the slower sub-groups, we detected a statistically significant difference only in Group 3 (p<0.0001). Additionally, the C-allele frequency was higher in the faster sub-groups. However, the significant allele gene distribution was obtained only in Group 3 (p=0.0002). According to our results, we can speculate that the GC genotype is more advantageous than the GG genotype in cross-country skiing athletes.