title: Association between polymorphisms in the TRHR gene, fat-free mass, and muscle strength in older women.
abstract: A previous genome-wide association study suggested that polymorphisms in the thyrotrophin-releasing hormone receptor (TRHR) gene contribute to fat-free mass (FFM) variation. The aim of the present study was to examine the association between polymorphisms in the TRHR gene with FFM and muscle strength in older women. Volunteers (n = 241; age = 66.65 ± 5.5 years) underwent quadriceps strength assessment using isokinetics and fat-free mass by dual-energy X-ray absorptiometry. TRHR polymorphisms and ancestry-informative markers were genotyped through standard procedures. No significant difference was observed for rs7832552. Regarding the rs16892496, ANCOVA revealed that appendicular fat-free mass (AFFM) and relative AFFM were significantly different between groups (p = 0.04 and p = 0.05, respectively). Individuals carrying A/A and A/C genotypes respectively showed, on average, an extra 1 kg and 900 g of AFFM when compared to C/C genotype carriers. Also, the C/C genotype group presented a significantly higher chance to have reduced muscle strength. The observations presented here provide further evidence that the rs16892496 polymorphism in the TRHR gene may play a role in FFM variation. Moreover, the results bring the novel insight that this genetic variant can present a modest contribution to muscle strength in older women.
authors.affiliation: College of Physical Education, University of Brasilia, SMU/QRS/RCG, Rua E, Casa 504, Brasília, Distrito Federal, Brazil, claudia_lunardi@yahoo.com.br.
authors.forename: Cláudia C
authors.initials: CC
authors.lastname: Lunardi
authors.forename: Ricardo M
authors.initials: RM
authors.lastname: Lima
authors.forename: Rinaldo W
authors.initials: RW
authors.lastname: Pereira
authors.forename: Tailce K M
authors.initials: TK
authors.lastname: Leite
authors.forename: Ana B M
authors.initials: AB
authors.lastname: Siqueira
authors.forename: Ricardo J
authors.initials: RJ
authors.lastname: Oliveira
mesh_terms: D015502:Absorptiometry, Photon; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000235:genetics*; D001823:Body Composition; D004247:DNA / Q000235:genetics; D005260:Female; D055106:Genome-Wide Association Study; D005838:Genotype; D006801:Humans; D008875:Middle Aged; D009119:Muscle Contraction / Q000502:physiology*; D053580:Muscle Strength / Q000502:physiology*; D018482:Muscle, Skeletal / Q000033:anatomy & histology* / Q000502:physiology*; D010641:Phenotype; D011110:Polymorphism, Genetic; D018025:Receptors, Thyrotropin-Releasing Hormone / Q000235:genetics* / Q000378:metabolism
chemical_list: D018025:Receptors, Thyrotropin-Releasing Hormone; D004247:DNA
references.citation: J Sports Sci Med. 2005 Sep 01;4(3):285-90
references.pmid: 24453533
references.citation: J Epidemiol. 2011;21(4):240-5
references.pmid: 21498954
references.citation: Hypertension. 2001 Sep;38(3 Pt 2):683-7
references.pmid: 11566956
references.citation: J Clin Densitom. 2007 Apr-Jun;10(2):174-8
references.pmid: 17485035
references.citation: J Am Geriatr Soc. 1987 Jan;35(1):13-20
references.pmid: 3794141
references.citation: J Am Coll Nutr. 1988 Dec;7(6):471-83
references.pmid: 3068276
references.citation: Am J Physiol. 1996 Feb;270(2 Pt 1):E320-7
references.pmid: 8779955
references.citation: J Appl Physiol (1985). 2009 May;106(5):1604-10
references.pmid: 19228990
references.citation: Am J Med. 2008 Sep;121(9):811-9
references.pmid: 18724972
references.citation: Am J Hum Genet. 2009 Mar;84(3):418-23
references.pmid: 19268274
references.citation: Physiol Genomics. 2008 Sep 17;35(1):36-44
references.pmid: 18682575
references.citation: Int J Sports Med. 2011 Jan;32(1):66-72
references.pmid: 21072744
references.citation: J Appl Physiol (1985). 1997 Jul;83(1):229-39
references.pmid: 9216968
references.citation: J Clin Densitom. 2009 Jan-Mar;12(1):35-41
references.pmid: 19084449
references.citation: J Appl Physiol (1985). 2008 Nov;105(5):1498-503
references.pmid: 18818386
references.citation: Hum Biol. 1976 Feb;48(1):161-73
references.pmid: 1254283
references.citation: Med Sci Sports Exerc. 2006 Jun;38(6):1074-81
references.pmid: 16775548
references.citation: Int J Sports Med. 2007 Dec;28(12):1065-9
references.pmid: 17614034
references.citation: J Aging Phys Act. 2009 Jan;17(1):31-45
references.pmid: 19299837
references.citation: J Am Geriatr Soc. 2004 Jan;52(1):80-5
references.pmid: 14687319
references.citation: Nucleic Acids Res. 1988 Feb 11;16(3):1215
references.pmid: 3344216
references.citation: FASEB J. 2010 Feb;24(2):393-403
references.pmid: 19825978
references.citation: Am J Epidemiol. 1998 Apr 15;147(8):755-63
references.pmid: 9554417
references.citation: Med Sci Sports Exerc. 2003 Aug;35(8):1381-95
references.pmid: 12900694
references.citation: J Gerontol A Biol Sci Med Sci. 2007 Sep;62(9):966-72
references.pmid: 17895434
references.citation: J Physiol. 1994 Nov 15;481 ( Pt 1):149-61
references.pmid: 7853237
references.citation: Med Sci Sports Exerc. 2010 May;42(5):835-46
references.pmid: 20400881
references.citation: J Bone Miner Res. 1997 Dec;12(12):2076-81
references.pmid: 9421240
references.citation: J Gerontol A Biol Sci Med Sci. 2001 May;56(5):B209-17
references.pmid: 11320101
references.citation: Endocr J. 2003 Aug;50(4):459-67
references.pmid: 14599121
references.citation: Hum Genet. 2012 Jan;131(1):1-31
references.pmid: 21706341
references.citation: J Appl Physiol (1985). 1988 Sep;65(3):1147-51
references.pmid: 3182484
references.citation: Med Sci Sports Exerc. 2004 Jul;36(7):1132-9
references.pmid: 15235316
references.citation: J Appl Physiol (1985). 2000 Nov;89(5):1879-83
references.pmid: 11053339