Association Of Methylenetetrahydrofolate Reductase C677T Gene Polymorphism And Related Metabolites With Inner Ear Disease

Objective:To investigate the association of methylenetetrahydrofolate reductase C677 T gene polymorphism and related metabolites,including serum Hcy,serum folate and vitamin12,with inner ear disease.In addition,The disease group was classified according to the clinical diagnosis,and the grouping analysis was conducted to further study the relationship between each classification of inner ear diseases and MTHFR gene polymorphism and related metabolites,to provides guidance for the prevention and clinical diagnosis and treatment of the mechanism of inner ear disease.Methods:Totally 175 Patients with inner ear diseases hospitalized in our department from April to November 2019 and 175 healthy subjects in the same period were selected as the disease group and the control group respectively.The results of MTHFR C677 T gene polymorphism,serum homocysteine(Hcy),and folic acid were collected from the two groups.we perform comparative analysis and risk analysis of inner ear diseases.According to the clinical diagnosis,the disease group was classified as sudden sensorineural hearing loss group(SSHL group),meniere’s disease group(MD group),sensorineural hearing loss group(SHL group),vestibular dysfunction group(VD group),then the results of MTHFR C677 T gene polymorphism,serum Hcy,serum folic acid and VB12 in each group were comparetivelyanalyzed and the risk of disease was analyzed.Results:1.The frequency of MTHFR C677 T genotype CC in the disease group was lower than in the control group,and the frequency of CT+TT was higher than in the control group,the difference was statistically significant(P<0.05).The frequency of CT type or TT type was slightly higher than in the control group(P>0.05).The risk of inner ear disease of CT+TT type was 1.397 times higher than that of CC type(P<0.05),CT and TT were 1.408 times higher than CC type(P<0.05)and 1.375 times higher than CC type respectively(P>0.05).The frequency difference between alleles C and T was statistically significant(P<0.05),and the risk of inner ear disease in T was 1.264 times higher than that in C(P<0.05).The abnormal rate of serum Hcy in the disease group was higher than that in the control group,and the difference was statistically significant(P<0.05).The mean serum Hcy concentration of each genotypein the disease group was higher than the control group,with only statistically significant difference in TT type(P<0.05).There were statistically significant differences in the mean serum Hcy concentration and abnormal rate among genotypes in the disease group(all P =0.000).The risk of Hcy abnormality in CC type was 0.762 times in CT type(P>0.05)and 0.207 times in TT type(P<0.05).The risk of Hcy abnormality in CT type was 0.272 times than TT type(P=0.000).The difference in serum folic acid level and abnormal rate among genotypes was not statistically significant(all P>0.05).2.Disease groups were grouped and each group was studied.In MD group,the CC frequency of MTHFR C677 T genotype was lower than the control group,and the frequency of CT+TT was higher than the control group(P<0.05).The difference of C、T allele frequency between the two groups was statistically significant(P<0.05).The risk of MD in CT+TT was 3.615 times that in CC(P<0.05).TT、CT was 4.476 times(P<0.05)、3.138 times(P>0.05),and T was 2.11 times higher than C.Compared with the control group,the difference of allele frequency of C、T in SSHL group or VD group was statistically significant(P<0.05).The risk of SSHL at T was 1.329 times than C(P<0.05),and the risk of Vestibular dysfunction was 1.676 times than C(P<0.05).In group A,The Hcy level and the Hcy level of each genotype were higher than those in the control group,and the differences were statistically significant in TT type(P<0.05).The overall abnormal rate of Hcy and the abnormal rate of Hcy in TT type were higher than those in the control group,and the differences were statistically significant(P<0.05).There were statistically significant differences in the distribution of Hcy levels and abnormal rates among genotypes in SSHL group(P<0.05).The risk of Hcy abnormalities in TT genotypes was 3.333 times than CC,4.083 times than CT genotypes(all P<0.05).In MD group,there were statistically significant differences in the distribution of Hcy,folic acid and VB12 levels among all genotypes(P<0.05),TT Hcy level was higher than that of CT type(P>0.05),folic acid level was lower than that of CT type(P>0.05),folic acid level was lower than that of CT type(P>0.05),and vitamin B12 level was lower than that of CT type(P<0.05).There were no statistically significant differences in serum Hcy,folic acid,VB12 levels and abnormal rates among genotypes in group A,group C,group D(P>0.05).Conclusion:1.MTHFR C677 T gene polymorphism is associated with inner ear disease,and T allele can be a risk factor for inner ear disease.MTHFR C677 T mutation can increase the risk of inner ear disease,especially the heterozygous mutation CT type.Serum homocysteine level is associated with inner ear disease.MTHFR gene polymorphism can increase the risk of increased serum homocysteine level,thus affecting the inner ear,especially homozygous mutation TT type,but not significantly correlated with serum folic acid level.2.MTHFR C677 T gene polymorphism is associated with meniere’s disease and can significantly increase the risk of meniere’s disease.Especially,TT type is prominent.T allele can be a risk factor for meniere’s disease and T allele mutation may also affectthe incidence of sudden deafness vestibular dysfunction,which needs to be further demonstrated by expanding the sample size.3.Serum Hcy is associated with sudden deafness and can be a risk factor for the occurrence of sudden deafness.MTHFR gene polymorphism can increase the risk of increased serum Hcy.In particular,TT type MTHFR gene polymorphism can also affect serum folic acid VB12 level,which is obvious in meniere’s disease and should be paid attention to.4.MTHFR C677 T gene polymorphism and related metabolites have nothing to do with sensorineural hearing loss,which may be related to the insufficient sample size and sample source,and worth to further discussion.