Polymorphisms in the CNTF and CNTF receptor genes are associated with muscle strength in men and women

• Published in: Journal of applied physiology (1985) Vol. 102; no. 5; pp. 1824 - 1831
• Main Authors: De Mars, Gunther, Windelinckx, An, Beunen, Gaston, Delecluse, Christophe, Lefevre, Johan, Thomis, Martine A. I
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Am Physiological Soc 01.05.2007; American Physiological Society
• Subjects: Adult; Age; Age Factors; Aged; Aging - genetics; Biological and medical sciences; Ciliary Neurotrophic Factor - genetics; Cohort Studies; Correlation analysis; Female; Females; Fundamental and applied biological sciences. Psychology; Gene Frequency; Genes; Genotype; Genotype & phenotype; Gerontology; Height; Humans; Knee; Longitudinal Studies; Male; Middle Aged; Muscle Strength - genetics; Muscle Strength - physiology; Muscle, Skeletal - physiology; Muscular system; Phenotype; Polymorphism; Receptor, Ciliary Neurotrophic Factor - genetics; Sex Factors; Torque; Weight; Human; Senescence; Ageing; Sex; Ciliary neurotrophic factor; sex-specific differences; Vertebrata; Mammalia; Gene; association analysis; peak torque; Muscle force; Female; aging; Polymorphism; Biological receptor
• ISSN: 8750-7587; 1522-1601
• DOI: 10.1152/japplphysiol.00692.2006

Department of Biomedical Kinesiology, Research Center for Exercise and Health, Faculty of Kinesiology and Rehabilitation Sciences, Katholieke Universiteit Leuven, Leuven, Belgium Submitted 20 June 2006 ; accepted in final form 30 January 2007 Genotypic associations between polymorphisms in the ciliary neurotrophic factor (CNTF) and CNTF receptor (CNTFR) genes and muscular strength phenotypes in 154 middle-aged men (45–49 yr) and 138 women (38–44 yr) and 99 older men (60–78 yr) and 102 older women (60–80 yr) were tested to validate earlier association studies. Allelic interaction effects were hypothesized between alleles of CNTF and CNTFR. We performed analysis of covariance with age, height, and fat-free mass (FFM) as covariates. FFM was anthropometrically estimated by the equation of Durnin-Womersley. Isometric, concentric, and eccentric torques for the knee flexors (KF) and extensors (KE) were measured using Biodex dynamometry. In the older male group, T-allele carriers of the C-1703T polymorphism in CNTFR performed significantly better on all noncorrected KF torques, whereas only noncorrected KE isometric torque at 120° and concentric torque at 240°/s were higher than the C/C homozygotes ( P < 0.05). When age, height, and FFM were used as covariates, T-allele carriers performed only better on KE and KF isometric torque at 120° ( P < 0.05). Concentric KF torque at 180°/s was lower in middle-aged female A-allele carriers compared with the T/T subjects for the T1069A polymorphism in CNTFR. After correction for age, height, and FFM, middle-aged female A-allele carriers exhibited lower values on all concentric KF strength measures and isometric torque at 120°. There was a lack of association with the CNTF G-6A polymorphism in men, with inconclusive results for a limited number of phenotypes in women. No significant CNTF/CNTFR allele interaction effects were found. Results indicate that CNTFR C-1703T and T1069A polymorphisms are significantly associated with muscle strength in humans. ciliary neurotrophic factor; association analysis; peak torque; aging; sex-specific differences Address for reprint requests and other correspondence: G. De Mars, Dept. of Biomedical Kinesiology, Research Center for Exercise and Health, Faculty of Kinesiology and Rehabilitation Sciences, Katholieke Universiteit Leuven, B-3001 Leuven, Belgium (e-mail: martine.thomis{at}faber.kuleuven.be )