In the case of using post-race serum myoglobin concentration as the grouping variable, the total genotype score would also be different between low and high myoglobin responders (5.2±1.7 vs. 4.4±1.5 point, P = 0.02) which confirms the importance of having an advantageous genotype combination to reduce the probability of acute renal failure as the result of exertion rhabdomyolysis. The gene discussed is MB; the disease is rhabdomyolysis.