Association Study Of Alcohol Dependence And Dopamine D2(TaqIA,TaqIB,-141C), D4 Receptor Gene And DAT Gene Polymorphism

Objective:Alcohol dependence syndrome is a complex disorder which is influenced by physiological,psychological,environmental factors and individual inheritance and so on.Orthodox study mode on multiple factor disease and large sample perspective study indicate that hereditary factor is a considerable role in the process of alcohol dependence pathogenesis.In the present study,we invest the association of dopamine D2(TaqIA,TaqIB,-141C),D4 receptor gene and DAT gene polymorphism with alcohol dependence in Yunnan of China,and may give the new evidence for etio pathogenesis and clinical therapy of alcohol dependence syndrome.Methods:Three milliliter venous blood sample is obtained from each patient of the alcohol dependent group and health control group.After adding EDTA-Na₂ to prevent the blood from coagulating,DNA was extracted,Genotype and allele frequencies of polymorphism in five genes were examined by polymerase chain reaction and restriction fragment length polymorphism technique,polymerase chain reaction and variable number of tandem repeat technique in 80 alcohol dependence patients and 70 normal controls.All statistics were performed on SPSS 15.0 and HWSIM.Results:Genotypes of TaqIA in patients with alcohol dependence syndrome,type A1/A1 were found in 7 cases(8.8%),type A1/A2 were found in 45 cases(56.3%),type A2/A2 were found in 28 cases(35%);in the healthy control group,type A1/A1 were found in 15 cases(21.4%),type A1/A2 were found in 30 cases(42.9%),type A2/A2 were found in 25 cases(35.7%).Genotypes of TaqIB in patients with alcohol dependence syndrome,type B1/B1 were found in 29 cases(36.3%),type B1/B2 were found in 46 cases(57.5%),type B2/B2 were found in 5 cases(6.3%);in the healthy control group,type B1/B1 were found in 21 cases(30%),type B1/B2 were found in 33 cases(47.1%),type B2/B2 were found in 16 cases(22.9%).Genotypes of-141C in patients with alcohol dependence syndrome,type -141C Del/Del were found in 1 cases(1.3%),-141C Ins/Del were found in 12 cases(15%),-141C Ins/Ins were found in 67 cases(83.8%);in the healthy control group,type -141C Ins/Del were found in 11 cases(15.7%),-141C Ins/Ins were found in 59 cases(84.3%).Genotypes of DAT in patients with alcohol dependence syndrome,type 11/8 were found in 1 cases(1.3%), 10/10 were found in 1 cases(1.3%),11/11 were found in 66 cases(83.5%),11/10 were found in 6 cases(7.5%),12/11 were found in 6 cases(7.5%);in the healthy control group,type 11/8 were found in 1 cases(1.4%),10/10 were found in 2 cases(2.9%), 11/11 were found in 55 cases(78.6%),11/10 were found in 10 cases(14.3%),12/11 were found in 2 cases(2.9%).Genotypes of DRD4 in patients with alcohol dependence syndrome,type 2/2 were found in 62 cases(77.5%),type 2/4 were found in 18 cases(22.5%);in the healthy control group,type 2/2 were found in 62 cases(88.6%),type 2/4 were found in 8 cases(11.4%).The genotype and allele frequencies of DRD2 gene TaqIB polymorphism differed significantly between dependence group and control group(P＜0.05).B2 allele may be a protective factor to alcohol dependence syndrome(OR:0.225,P＜0.05). At the same time,we found the combination of genotypes H14,"B2-B2-11-11-2-2", may be also a protective factor to alcohol dependence syndrome as a reference to HI,"B1-B1-11-11-2-2"(OR:0.133,P＜0.05).Conclusion:There were no significant association in DRD2 receptor gene TaqIA polymorphism,DRD4 48bp VNTR and DAT 40bp VNTR between patients and normal controls.However,TaqIB polymorphism has an association with alcohol dependence. B2 allele and the combination of genotypes H14,"B2-B2-11-11-2-2",may be a protective factor to alcohol dependence syndrome in Yunnan of China.