Key result
Baseline muscle specific force was significantly higher in PTK2 rs7843014 AA and rs7460 TT homozygotes compared to their respective C- and A-allele carriers, though training responses were similar.
Why the study?
Do PTK2 gene polymorphisms affect baseline muscle strength and the response to 9 weeks of resistance training in untrained young men?
Observational (n=51)
No
Do PTK2 gene polymorphisms affect baseline muscle strength and the response to 9 weeks of resistance training in untrained young men?
PTK2 gene polymorphisms are associated with baseline muscle specific force, suggesting genetic variation impacts the intrinsic strength of human skeletal muscle.
Answers are grounded in this paper and cite their sources.
PTK2 variants associate with baseline muscle force; hypothesis-generating for genetic influences on intrinsic strength, with no training-response implications yet.
The protein tyrosine kinase-2 (PTK2) gene encodes focal adhesion kinase, a structural protein involved in lateral transmission of muscle fiber force. We investigated whether single-nucleotide polymorphisms (SNPs) of the PTK2 gene were associated with various indexes of human skeletal muscle strength and the interindividual variability in the strength responses to resistance training. We determined unilateral knee extension single repetition maximum (1-RM), maximum isometric voluntary contraction (MVC) knee joint torque, and quadriceps femoris muscle specific force (maximum force per unit physiological cross-sectional area) before and after 9 wk of knee extension resistance training in 51 untrained young men. All participants were genotyped for the PTK2 intronic rs7843014 A/C and 3'-untranslated region (UTR) rs7460 A/T SNPs. There were no genotype associations with baseline measures or posttraining changes in 1-RM or MVC. Although the training-induced increase in specific force was similar for all PTK2 genotypes, baseline specific force was higher in PTK2 rs7843014 AA and rs7460 TT homozygotes than in the respective rs7843014 C- (P = 0.016) and rs7460 A-allele (P = 0.009) carriers. These associations between muscle specific force and PTK2 SNPs suggest that interindividual differences exist in the way force is transmitted from the muscle fibers to the tendon. Therefore, our results demonstrate for the first time the impact of genetic variation on the intrinsic strength of human skeletal muscle.
No takes yet. Share an insight, caveat, or question.
Erskine et al. (2012) conducted an observational in Healthy untrained men (n=51). PTK2 gene polymorphisms (rs7843014 and rs7460) vs. Alternative alleles/genotypes was evaluated on Baseline quadriceps femoris muscle specific force (p=0.016 and 0.009). Baseline muscle specific force was significantly higher in PTK2 rs7843014 AA and rs7460 TT homozygotes compared to their respective C- and A-allele carriers, though training responses were similar.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: