Research On The Relationship Between ADH2, CYP2E1 Gene Polymorphism And Alcohol Dependence Syndrome

[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,by detecting the genetic polymorphisms of ADH2 and CYP2E1,to study the difference of the genotypes and the allele frenquencies in the following two groups:alcoholic dependence group,healthy control group.We hope to reveal the genetic relevance between alcohol dependence syndrome with the two candidate gene,and may give the new evidence for etiopathogenesis and clinical therapy of alcohol dependence syndrome.[Method]:Two milliliter venous blood sample is obtained from each patient of the health control group and alcohol dependent group,each group contains 30 patients at least.After adding EDTA to prevent the blood from coagulating,DNA was extracted,then polymerase chain reaction is performed.Adjust the reaction condition,exam whether there has been some amplification product is by polyacrylamide gel electrophoresis.An aliquot of the ampified DNA fragments by polymerase chain reaction were treated with two types of restriction endonucleases:MaeⅢor PstⅠ.The genotypes of ADH2 was separated into three types:ADH2~*1/ ADH2~*1,ADH2~*1/ ADH2~*2,ADH2~*2/ ADH2~*2,exist two allele:ADH2~*1 or ADH2~*2;The genotypes of CYP2E1 was separated into three types:c1/c1,c1/c2,c2/c2,exist two allele:c1 or c2.The digested products ara run on polyacrylamide gel electrophoresis to determined the genotypes of each gene.All samples were test by Hardy-Weinberg balance,the findings of study were analyzed by Chi square.[Result]:Genotypes of ADH2 in patients with alcohol dependence syndrome,type ADH2~*1/ADH2~*1 was found in 16 patients(36%),type ADH2~*1/ADH2~*2 was found in 19 patients(43%),type ADH2~*2/ADH2~*2 was found in 9patients(21%);in the healthy control group,type ADH2~*1/ADH2~*1 was found in 6patients(20%),type ADH2~*1/ADH2~*2 was found in 11 patients(37%),type ADH2~*2/ADH2~*2 was found in 13 patients(43%).The frenquency of genotype in alcohol dependence group and health control group has no statistic significance(P＞0.05).The frenquency of ADH2~*1 allele in alcohol dependence group is 0.58,in health control group is 0.38.The frenquency of ADH2~*2 allele in alcohol dependence group is 0.42,in health control group is 0.62.The frenquency of ADH2~*1 allele,ADH2~*2 allele in alcohol dependence group and health control group has statistic significance(P＜0.05).The frenquency of ADH2~*2 allele in alcohol dependence group is lower than another group.Genotypes of CYP2E1 in alcohol dependence patients,type A was found in 26 patients(59%),type B was found in 18 patients(41%);in the healthy control group,type A was found in25 patients(83%),type B was found in 5 patients(17%),type C are not found in each group.There has difference in the frenquency of genotype in alcohol dependence group compared with health control group(P＜0.05),type B was higher in alcohol dependence group.The frenquency of c1 allele in alcohol dependence group is 0.80,in health control group is 0.92.The frenquency of c2 allele in alcohol dependence group is 0.20,in health control group is 0.08.There is statistic significance of c2 allele in alcohol dependence group and health control group(P＜0.05).The frenquency of c2 allele in alcohol dependence group is higher than another group.[Conclusion]:The date were statistical analyzed.The frenquency of ADH2~*2 allele in alcohol dependence group is lower than another group but c2 allele is higher.Type B was higher in alcohol dependence group.The result suggest that susceptibility to alcohol dependence syndrome may be associated with the polymorphism of CYP2E1 gene,and c2 allele may be related to the morbility of alcohol dependence syndrome.ADH2~*2 allelemay be a protective factor to alcohol dependence syndrome.