Common genetic variation in the IGF1 associates with maximal force output

Area of Science:

• Genetics and Sports Science
• Molecular Biology
• Human Physiology

Background:

• Single nucleotide polymorphisms (SNPs) can alter gene expression and protein function, impacting biological processes.
• Insulin-like growth factor-1 (IGF1) is crucial for skeletal muscle anabolic pathways.
• Interleukin-6 (IL6) plays a role in muscle energy homeostasis during exercise.

Purpose of the Study:

• To investigate the association between gene variants in IGF1, IGFBP3, IL6, and IL6R and physical performance.
• To examine the relationship between these gene variants and body composition.
• To determine the effect of these variants on circulating levels of IGF-1 and IL-6.

Main Methods:

• Genotyping of 841 healthy Finnish males for specific SNPs in IGF1, IGFBP3, IL6, and IL6R.
• Assessment of maximal force, maximal oxygen consumption, and body fat percentage.
• Measurement of circulating IGF-1 and IL-6 levels using ELISA and PCR assays.

Main Results:

• The IGF1 SNP rs7136446 (genotype CC) was associated with higher body fat and increased maximal force production.
• The IGFBP3 SNP rs2854744 (genotype CC) and IL6R SNP rs4537545 (genotype TT) were linked to higher IL-6 levels.
• No significant associations were found between the studied SNPs and aerobic performance.

Conclusions:

• Common variations in the IGF1 gene may influence maximal force production due to IGF1's role in muscle anabolism.
• Variations in IGF1 and IGFBP3 genes might contribute to higher body fat and altered IGF1-mediated tissue growth.