Kcnj11 Gene Polymorphism And Endurance Performance Status In Hispanics

Abstract

An association between a DNA sequence variant in the K+ inwardly rectifying channel, subfamily J, member 11 (KCNJ11) gene and elite endurance athlete status was recently reported (MSSE 35(5):S379, 2003). PURPOSE To examine the hypothesis of an association between the same KCNJ11 gene polymorphism and endurance performance status in Hispanics. METHODS DNA samples were successfully genotyped from 171 Hispanics subjects. Cases (n = 98) were long distance runners finishers in the highest 3 percentile, by age and gender, during their participation in an international marathon (42 km) race, while controls (n = 73) were subjects with severely compromised cardiorespiratory functions. The polymorphism was detected by PCR and digestion with Ban II endonuclease. RESULTS The three expected KCNJ11-BanII genotypes were observed in both genders and groups. These genotype frequencies, within each gender, were in Hardy-Weinberg equilibrium (X2, P>0.05) and not different (X2, P>0.05) different between genders. There was no gender difference (X2, P>0.05) in allelic frequencies. Chi-square analysis for the pooled data for both genders revealed significant differences in genotype (cases; TT = 8%, TC = 47%, CC = 45% and controls; TT = 28%, TC = 38%, CC = 34%; Chi-square = 7.7, df = 2, P = 0.02) and allele (Cases; T = 32%, C = 68% and Controls; T = 47%, C = 53%; Chi-square = 4.0, df = 1, P = 0.04) frequencies between the cases and controls. CONCLUSION As in previously shown (MSSE 35(5):S379, 2003) in Caucasians, an excess of the KCNJ11-BanII T allele is negatively associated with the complex phenotype of endurance performance status in Hispanics. Supported by CRC-RCMI 1P20RR11126, RCMI #G12RR03051, Comite de Fondismo: FPRA, Maraton Pacifico de Guardajara, and Maraton Popular de Madrid.