Determination of the Distribution of the rs2069514 and rs762551 Alleles of the Cyp1a2 Gene Related to Caffeine Metabolism in Professional Athletes

The objective of this study is to investigate allele distributions of the rs2069514 and rs762551 polymorphisms of the CYP1A2 gene which affect caffeine metabolism in long-distance and short-distance runners in the Turkish population. 20 professional athletes in total were included in the study within the age range of 18-24, 10 of whom were long-distance (female, n=5; Male, n=5) and 10 of whom were short-distance (Female, n=5; Male, n=5) runners. DNA isolation from the athletes was performed from peripheral blood samples and genotyping was determined using the technique of Real Time-PCR. According to the obtained data, the ratio of individuals having AA (n=6), GG (n=9) and AG (n=5) genotype for the region of rs2069514 was found as 30%, 45% and 25% respectively. On the other hand, the ratio for AA (n=4), CC (n=9) and AC (n=7) genotypes in the region of rs762551 allele was determined as 20%, 45% and 35%. According to the results, no significant variance regarding gender was found for either of the different polymorphisms under study in long-distance and short-distance runners while the genotype distributions varied between short and long-distance runners only in the rs2069514 polymorphism. The GG genotype was observed in 9 short-distance runners while it was observed in none of the long-distance runners. As a result, the fact that the GG genotype in case of the Rs2069514 polymorphism was observed in nine of the ten short-distance runners suggests that the athletes in this group metabolize caffeine slowly and this should be considered in the caffeine intake. 

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