Walpole B, Noakes T D, Collins M
UCT/MRC Research Unit for Exercise Science and Sports Medicine, University of Cape Town, Cape Town, South Africa.
Br J Sports Med. 2006 Feb;40(2):145-50; discussion 145-50. doi: 10.1136/bjsm.2005.020669.
Some studies have suggested that the insertion allele of the ACE gene is associated with endurance performance, including the Ironman triathlon. It is possible that this association is due to genetic linkage between the ACE I/D locus and the T/A variant in intron 4 of the neighbouring GH1 gene. The A variant is associated with lower levels of growth hormone production. Growth hormone has multiple effects, especially on metabolism during exercise and recovery from exercise. Its production during exercise has also been shown to stimulate sweat rate and heat loss.
To determine whether the GH1 gene is associated with the performance and/or post-race rectal temperatures of competitors in the South African Ironman triathlon.
A total of 169 of the fastest finishing white male triathletes who completed the 2000 and/or 2001 South African Ironman triathlon and 155 control subjects were genotyped for the T/A variant in the GH1 gene. Post-race rectal temperature was also determined in 103 of these triathletes.
There was no significant difference in the frequency of this polymorphism in the GH1 gene when the fastest finishing triathletes were compared with the control subjects. Post-race rectal temperatures were, however, significantly higher in those triathletes with an AA genotype (mean (SD) 37.7 (0.8) degrees C) compared with those with a TT genotype (37.2 (0.8) degrees C) (p = 0.019).
The T/A polymorphism in intron 4 of the GH1 gene was not associated with performance of the fastest finishers of the South African Ironman triathlon. Post-race rectal temperatures were, however, significantly higher in the fastest finishing athletes, who were homozygous for a GH1 genotype associated with lower growth hormone production.
一些研究表明，ACE基因的插入等位基因与耐力表现有关，包括铁人三项赛。这种关联可能是由于ACE I/D基因座与相邻GH1基因内含子4中的T/A变体之间的遗传连锁。A变体与较低水平的生长激素分泌有关。生长激素有多种作用，尤其是对运动期间及运动恢复过程中的新陈代谢。运动期间其分泌还被证明会刺激出汗率和热量散失。
确定GH1基因是否与南非铁人三项赛参赛者的表现和/或赛后直肠温度有关。
对169名完成2000年和/或2001年南非铁人三项赛的成绩最快的白人男性铁人三项运动员以及155名对照受试者进行了GH1基因T/A变体的基因分型。还测定了其中103名铁人三项运动员的赛后直肠温度。
将成绩最快的铁人三项运动员与对照受试者相比，GH1基因中这种多态性的频率没有显著差异。然而，AA基因型的铁人三项运动员赛后直肠温度（均值（标准差）37.7（0.8）℃）显著高于TT基因型的运动员（37.2（0.8）℃）（p = 0.019）。
GH1基因内含子4中的T/A多态性与南非铁人三项赛成绩最快者的表现无关。然而，在成绩最快的运动员中，那些GH1基因型为纯合子且与较低生长激素分泌相关的运动员，其赛后直肠温度显著更高。
