Association Between The Genetic Polymorphism Of Superoxide Dismutase And The Development Of Chronic Obstructive Pulmonary Disease

Object Chronic Obstructive pulmonary disease(COPD)is a disease characterized by airflow limitation that is not fully reversible.The airflow limitation is usually progressive and results from an abnormal inflammatory response of the lung to noxious particle and gas.COPD is charaterized on chronic inflammation throughout airway lung parenchyma and pneumoangiogram.Besides inflammatory mechanism,it also has other two mechanisms:out-of-balance between oxidizing and anti-oxidizing and out-of-balance between protease and anti-protease which do effort on the happening of COPD.In addition,smoking or touching the polluted environment can also cause the inflammatory of lung tissue,lt has been identified that COPD is the result of an environmental insult and the response of the host that is primarily genetically predetermined. However,only a few of genetic risk factors of COPD are established.Other genetic risk factors of COPD are uncertained.We investigated whether polymorphisms in gene for superoxide dismutase(SOD)have any relations on individual susceptibility to the development of COPD in order to find out the "susceptible" gene for COPD.We can select the high dangerous population to prevent earlier and reduce the incidence of COPD. Materials and Methods The research design was a case-control study.We select the limosis peripheral blood of 70 COPD patients (group COPD)and 70 healthy volunteers(group control subjects).We extracted their whole blood corpuscle genomic DNA.Polymerase chain reaction and restriction fragment length polymorphism(PCR-RFLP)were performed to delect genetic polymorphism of SODI,SOD2 and SOD3 genes in two groups.The data of age and smoke index of this study were analyzed by t test,the data of frequency of genetype were analyzed by Chi square.Results 1.SOD1 homozygous wild-type(AA)and heterozygote(AC) was 92.86%,7.14%in COPD group and 91.43%,8.57%in control group.There are no homozygous mutant(CC)in two groups.X~2 test shows no difference between twogroups(P>0.05).2.SOD2 homozygous wild-type(TT,Val/Val),heterozygote(ZC,Val/Ala)and homozygous mutant(CC,Ala/Ala)was 22.86%,51.43%,25.71%in COPD group and 20.00%,55.71%,24.29%in control group.X~2 test shows no difference between two groups(P>0.05).3.SOD3 homozygous wild-type(CC,Arg/Arg)and heterozygote(CG,Arg/Gly)was 87.14 %,12.86%inCOPD group and 98.57%,1.43%in control group.There are no homozygous mutant(GG,Gly/Gly)in two groups.X~2 test shows that there is logistic difference between two groups.Conclusions 1.The genetic polymorphism of SODI(CuZn-SOD)is not associated with the development of COPD.2.The genetic polymorphism of SOD2(Mn-SOD)is not associated with the development of COPD.3.The genetic polymorphism(C+637G, Arg213Gly)of SOD3(EC-SOD)is associated with the development of COPD.It maybe the correlative gene of COPD.