Gut bacteria alteration in obese people and its relationshipwith gene poymorphism

AIM：To investigate the differences in cultivable gut bacteria and peroxisome proliferator-activated receptor γ2（PPAR-γ2） gene Pro12Ala variation in obese and normal-weight Chinese people.METHODS：Using culture methods,the amounts of Escherichia coli,Enterococci,Bacteroides,Lactobacilli,Bif idobacteria and Clostridium perfringens（C.perfringens） in the feces of 52 obese participants [body mass index（BMI）：≥ 28 kg/m2] and 52 participants of normalweight（BMI：18.5-24 kg/m2） were obtained.Study participants completed comprehensive questionnaires and underwent clinical laboratory tests.The polymerase chain reaction-restriction fragment length polymorphism（PCR-PFLP） assay was used to analyze PPAR-γ2 gene Pro12Ala variation.RESULTS：The obese group exhibited a lower amount of C.perfringens（6.54 ± 0.65 vs 6.94 ± 0.57,P = 0.001）and Bacteroides（9.81 ± 0.58 vs 10.06 ± 0.39,P = 0.012） than their normal-weight counterparts.No major differences were observed in Pro12Ala genotype distribution between the two groups;however,obese individuals with a Pro/Ala genotype had a signif icantly lower level of Bacteroides（9.45 ± 0.62 vs 9.93 ± 0.51,P = 0.027） than those with a Pro/Pro genotype.In addition,the obese group demonstrated a higher stool frequency（U = 975,P 〈 0.001） and a looser stool（U = 1062,P = 0.015） than the normal-weight group.CONCLUSION：Our results indicated interactions among cultivable gut flora,host genetic factors and obese phenotype and this might be helpful for obesity prevention.