The Correlation Between SCD And MTHFR Gene Polymorphism

ObjectiveSubacute combined degeneration of spinal cord(SCD)is one of the few clinical curable diseases of the nervous system.The key to cure is early diagnosis and timely treatment,otherwise it will lead to irreversible damage and disability of the nervous system.The pathogenesis of SCD is unknown,and most scholars believe that it may be related to vitamin B12 deficiency,but it is found that some patients are not complicated with vitamin B12 deficiency,so the etiology of SCD needs to be confirmed by further study.At present,there is no discussion on the etiology of SCD from the perspective of genetics at home and abroad.Through the case-control method,this study attempts to find that MTHFR gene polymorphism is the genetic susceptibility factor leading to SCD and its possible mechanism,in order to further clarify the pathogenesis of SCD from the perspective of genetics,and provide new scientific basis for early diagnosis,treatment and prevention of SCD.MethodsAfter the approval of the Ethics Committee of Shaanxi Provincial people's Hospital,the study was successively included as the case group in the Department of Neurology of Shaanxi people's Hospital from August 2018 to March 2020 as the case group;at the same time,other patients hospitalized in the Department of Neurology of Shaanxi Provincial people's Hospital in the same period were included as the control group,both groups of patients met the inclusion and exclusion criteria,and all patients signed the informed consent form.In this study,the clinical data of the two groups,including age,sex and past medical history,were analyzed and compared by case-control study,and venous blood samples were taken to detect MTHFR C677T and MTHFR A1298C gene polymorphism,serum Hcy concentration,vitamin B12 level and so on.The counting data were expressed as percentage(%),?2 test was used,the correlation between serum vitamin B12 and Hcy was analyzed by linear correlation analysis,and the advantage of 95%confidence interval(95%CIs)was estimated by logistic regression analysis compared with(ORs),to identify the risk factors of SCD.The difference was statistically significant(P<0.05).All the data were analyzed by SPSS 22.0 statistical software.Results:1.According to the inclusion and exclusion criteria,149 patients were included in the study,including 52 patients in the case group and 97 patients in the control group.There was no significant difference in age and sex between the two groups.2.Through the comparison of Hcy concentration,vitamin B12 concentration,folic acid concentration and history of large cell anemia between the two groups,the serum Hcy concentration in the case group(62.015 ? mol/L)was significantly higher than that in the control group(16.910 ? mol/L/L)(P<0.001).There were significant differences in the history of large cell anemia and the rate of vitamin B12 deficiency between the two groups(P<0.001),but there was no significant difference in folic acid concentration between the two groups(P<0.01).3.There was a significant difference in MTHFR C677T genotype polymorphism between the case group and the control group(Please 0.015).The frequency of T allele in the case group was significantly higher than that in the control group(70.2 vs.52.6%),while the frequency of C allele in the case group was lower than that in the control group(24.2 vs.48.1%).However,there was no significant difference in MTHFR A1298C gene polymorphism between the two groups.4.The MTHFR gene polymorphism C677T was divided into three genotypes.There was significant difference in the median plasma homocysteine concentration among the three groups(H=27.205,P<0.001).After pairwise comparison,there was significant difference in plasma HCY concentration between 677CC group and 677TT group,and between 677CC group and 677CT group(P<0.001).However,there was no significant difference in plasma B12 and folic acid concentrations among the three groups(P=0.439 and P=0.773).5.There was a weak negative linear correlation between plasma homocysteine and vitamin B12 concentration in all participants(rs=-0.450,P<0.001).No correlation was found between homocysteine and folic acid.6.MTHFR C677T gene polymorphism is associated with SCD,677T allele may be a risk factor,but MTHFR A1298C gene polymorphism is not significantly associated with SCD7.Univariate logistics regression analysis showed that homocysteine was an important risk factor for SCD,followed by vitamin B12 deficiency and 677TT genotypeConclusionThe results of this study show that MTHFR 677TT mutation is closely related to SCD in Chinese population and may be the genetic susceptibility factor of SCD.However,MTHFR A1298C gene polymorphism can not increase the risk of SCD.Studies have also shown that MTHFR 677TT mutation may affect the transformation of homocysteine to methionine by reducing the activity of methylenetetrahydrofolate reductase,thus affecting the synthesis of nerve myelin sheath.Therefore,the detection of MTHFR C677T gene polymorphism provides a basis for early diagnosis of SCD and theoretical basis for screening,diagnosis and prevention of SCD.