[Association between DIO polymorphism and aerobic endurance]

To study whether polymorphisms in the iodothyronine deiodinase (DIO) gene region contribute to endurance exercise capacity and to validate whether TSHR gene can be used as genetic marks associated with aerobic endurance performance.

Three SNPs (C785T in DIO1 gene regions, Thr92Ala and Gly3Asp in DIO2 gene regions) were selected. The genotypes of the 123 elite long running athletes(EEA) and 127 college students from northern China(CG) were analyzed using the matrix assisted laser desorption ionisation-time of flight mass spectrometry method(MALDI-TOF). The athletes were divided into different groups according to the sports level and the items, which are international masters and masters (43 vs 80), 5/10 km and marathon (92 vs 31).

There was no significant difference of the C785T loci in DIO1 gene and the Thr92Ala loci in DIO2 gene between the EEA and the CG(P＞0.05), while at Gly3Asp loci, the frequency distributions of the 3 genotypes were remarkably different in the groups of control and international masters of sports, as well as in the groups of control and marathon athletes(P＜0.05). The genotype TT only existed in EEA not in CG, however, the frequency distribution was very low. The Thr92Ala and Gly3Asp loci of DIO2 gene were in strong linkage disequilibrium. The frequency distributions of the haplotype CT were significantly different in the male CG and the female CG, the male CG and the male EEA(P＜0.05), the male CG and the male masters of sports, as well as in the male CG and the male marathon athletes(P＜0.05). The frequency distributions of the haplotype TC were remarkably higher in the groups of female international masters of sports and female 5 000 m/10 000 m than those in the female CG(P＜0.05).

The frequency distributions of the haplotype CT were different in male and female CG, and haplotype CT could be used as a genetic mark associated with aerobic endurance performance of the male EEA, especially for the long running athletes of masters of sports and marathon, while the haplotype CT was associated with the aerobic endurance performance of the female long running athletes of international masters of sports and 5 000 m/10 000 m.