Resistin polymorphisms are associated with muscle, bone, and fat phenotypes in white men and women.
OBJECTIVE
The biological function of resistin (RST) is unknown, although it may have roles in obesity, diabetes, and insulin resistance. The objective of this study was to examine the effects of single nucleotide polymorphisms (SNPs) in the human RST gene on muscle, bone, and adipose tissue phenotypes and in response to resistance training (RT).


METHODS
Subjects were white and consisted of strength (n = 482) and size (n = 409) cohorts who had not performed RT in the previous year. Subjects completed 12 weeks of structured, unilateral upper arm RT aimed at increasing the size and strength of the non-dominant arm, using their dominant arm as an untrained control. Strength measurements were taken pre- and post-12-week RT and consisted of elbow flexor isometric strength and one-repetition maximum during a biceps curl using free weights. Whole muscle, subcutaneous fat, and cortical bone volumes were measured by magnetic resonance imaging. Six RST SNPs were identified. Analysis of covariance was used to test for effects of the SNPs on pre- and post-muscle strength and whole muscle, fat, and bone volumes independent of gender, age, and body weight.


RESULTS
Five RST SNPs (-537 A>C, -420 C>G, 398 C>T, 540 G>A, 980 C>G) were associated with measured phenotypes among subjects when stratified by BMI (<25, >/ or = 25 kg/m(2)). Several gender-specific associations were observed between RST SNPs and phenotypes among individuals with a BMI > or = 25. Conversely, only two associations were observed among individuals with a BMI < 25.


CONCLUSIONS
These data support previous identified associations of RST with adipose tissue and demonstrate additional associations with bone and skeletal muscle that warrant further investigation.
Pistilli
Emidio E
EE
Division of Exercise Physiology, School of Medicine, West Virginia University, Morgantown, WV 26506-9227, USA.
Gordish-Dressman
Heather
H
Seip
Richard L
RL
Devaney
Joseph M
JM
Thompson
Paul D
PD
Price
Thomas B
TB
Angelopoulos
Theodore J
TJ
Clarkson
Priscilla M
PM
Moyna
Niall M
NM
Pescatello
Linda S
LS
Visich
Paul S
PS
Zoeller
Robert F
RF
Hoffman
Eric P
EP
Gordon
Paul M
PM
D050154:Adiposity / Q000235:genetics*; D015992:Body Mass Index; D001842:Bone and Bones / Q000033:anatomy & histology / Q000502:physiology; D015444:Exercise / Q000502:physiology; D005260:Female; D005787:Gene Frequency; D006801:Humans; D008297:Male; D053580:Muscle Strength; D018482:Muscle, Skeletal / Q000033:anatomy & histology / Q000502:physiology; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide; D052243:Resistin / Q000235:genetics*; D044465:White People / Q000235:genetics
C499624:RETN protein, human; D052243:Resistin