Polymorphism of human leptin receptor gene is associated with type 2 diabetic patients complicated with non-alcoholic fatty liver disease in China.
OBJECTIVE
To investigate the relationship between human leptin receptor (LEPR) gene G3057A polymorphism and type 2 diabetes mellitus (T2DM) patients complicated with or without non-alcoholic fatty liver disease (NAFLD).


METHODS
Two hundred and sixteen cases of newly diagnosed T2DM patients (104 cases complicated with NAFLD) and 108 cases of normal glucose tolerances (NGT) were recruited. Hemi-nested polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) and PCR-direct sequence analysis were conducted to detect the polymorphism of LEPR G3057A variation. Plasma leptin levels were measured by enzyme-linked immunosorbent assay kit. Plasma lipid and glucose metabolic parameters were measured routinely. Liver ultrasound was carried out for all subjects.


RESULTS
T2DM patients complicated with NAFLD had higher plasma insulin, leptin, triglycerides (TG) and low-density lipoprotein cholesterol (LDL-C) levels than those without NAFLD and NGT subjects. The variant frequency at nucleotide 3057 G-->A transversion was 76.0% in type 2 diabetic patients complicated with NAFLD, which was also significantly higher than those without NAFLD (62.1%) and NGT cases (53.2%). There was also significant difference in genotype distribution between the three groups (chi(2) = 14.63, P < 0.01).


CONCLUSIONS
The polymorphism of LEPR gene 3057 probably contributes to the onset of NAFLD by regulating lipid metabolism and affecting insulin sensitivity.
Lu
Hongyun
H
Department of Endocrinology, the Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, Guangdong, China. luhongyun1120@yahoo.com.cn
Sun
Jiazhong
J
Sun
Liao
L
Shu
Xiaochun
X
Xu
Yancheng
Y
Xie
Danhong
D
D000368:Aged; D044466:Asian People / Q000235:genetics*; D001786:Blood Glucose / Q000032:analysis; D016022:Case-Control Studies; D002681:China / Q000453:epidemiology; D008078:Cholesterol, LDL / Q000097:blood; D004252:DNA Mutational Analysis; D048909:Diabetes Complications / Q000097:blood / Q000208:ethnology / Q000235:genetics*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000150:complications / Q000208:ethnology / Q000235:genetics*; D005234:Fatty Liver / Q000097:blood / Q000208:ethnology / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006801:Humans; D007328:Insulin / Q000097:blood; D020738:Leptin / Q000097:blood; D008099:Liver / Q000737:chemistry / Q000000981:diagnostic imaging; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D054411:Receptors, Leptin / Q000235:genetics*; D018570:Risk Assessment; D012307:Risk Factors; D014280:Triglycerides / Q000097:blood; D014463:Ultrasonography
D001786:Blood Glucose; D008078:Cholesterol, LDL; D007328:Insulin; C515448:LEPR protein, human; D020738:Leptin; D054411:Receptors, Leptin; D014280:Triglycerides