Impact of common polymorphisms in candidate genes for insulin resistance and obesity on weight loss of morbidly obese subjects after laparoscopic adjustable gastric banding and hypocaloric diet.
BACKGROUND
It is unknown whether genetic factors that play an important role in body weight homeostasis influence the response to laparoscopic adjustable gastric banding (LAGB).


OBJECTIVE
We investigated the impact of common polymorphisms in four candidate genes for insulin resistance on weight loss after LAGB.


METHODS
The design was a 6-month follow-up study.


METHODS
The study setting was hospitalized care.


METHODS
A total of 167 unrelated morbidly obese subjects were recruited according to the following criteria: age, 18-66 yr inclusive; and body mass index greater than 40 kg/m2 or greater than 35.0 kg/m2 in the presence of comorbidities.


METHODS
LAGB was used as an intervention.


METHODS
Measure of correlation between weight loss and common polymorphisms in candidate genes for insulin resistance and obesity was the main outcome measure.


RESULTS
The following single nucleotide polymorphisms were detected by digestion of PCR products with appropriate restriction enzymes: Gly972Arg of the insulin receptor substrate-1 gene, Pro12Ala of the proliferator-activated receptor-gamma gene, C-174G in the promoter of IL-6 gene, and G-866A in the promoter of uncoupling protein 2 gene. Baseline characteristics including body mass index did not differ between the genotypes. At the 6-month follow-up after LAGB, carriers of G-174G IL-6 genotype had lost more weight than G-174C or C-174C genotype (P = 0.037), and carriers of A-866A uncoupling protein 2 genotype had lost more weight as compared with G-866G (P = 0.018) and G-866A (P = 0.035) genotype, respectively. Weight loss was lower in carriers of Gly972Arg insulin receptor substrate-1 genotype than Gly972Gly carriers, but not statistically significant (P = 0.06). No difference between carriers of Pro12Ala and Pro12Pro proliferator-activated receptor-gamma genotype was observed.


CONCLUSIONS
These data demonstrate that genetic factors, which play an important role in the regulation of body weight, may account for differences in the therapeutic response to LAGB.
Dipartimento Medicina Sperimentale e Clinica, Università Magna-Graecia di Catanzaro, Via Campanella, 115, 88100 Catanzaro, Italy. sesti@unicz.it
Giorgio
G
Sesti
Lucia
L
Perego
Marina
M
Cardellini
Francesco
F
Andreozzi
Cristina
C
Ricasoli
Paola
P
Vedani
Valeria
V
Guzzi
Monica
M
Marchi
Michele
M
Paganelli
Gianfranco
G
Ferla
Antonio E
AE
Pontiroli
Marta Letizia
ML
Hribal
Franco
F
Folli
D000328:Adult; D004038:Diet, Reducing; D005260:Female; D005500:Follow-Up Studies; D015391:Gastroplasty; D006579:Heterozygote; D006801:Humans; D055504:Insulin Receptor Substrate Proteins; D007333:Insulin Resistance / Q000235:genetics*; D015850:Interleukin-6 / Q000235:genetics; D007473:Ion Channels; D008297:Male; D026901:Membrane Transport Proteins / Q000235:genetics; D008875:Middle Aged; D024101:Mitochondrial Proteins / Q000235:genetics; D009767:Obesity, Morbid / Q000235:genetics* / Q000601:surgery*; D047495:PPAR gamma / Q000235:genetics; D010750:Phosphoproteins / Q000235:genetics; D020641:Polymorphism, Single Nucleotide; D011184:Postoperative Period; D000071246:Uncoupling Protein 2; D015431:Weight Loss / Q000235:genetics*
C526292:IRS1 protein, human; D055504:Insulin Receptor Substrate Proteins; D015850:Interleukin-6; D007473:Ion Channels; D026901:Membrane Transport Proteins; D024101:Mitochondrial Proteins; D047495:PPAR gamma; D010750:Phosphoproteins; C000604389:UCP2 protein, human; D000071246:Uncoupling Protein 2