The Clinical Research Between MTHFR And MTRR Gene Polymorphisms And Polycystic Ovary Syndrome

ObjectiveTo explore the clinical research between methylenetetrahydrofolate reductase(MTHFR)C677T,A1298C and methionine synthase reductase(MTRR)A66G gene polymorphisms and polycystic ovary syndrome(PCOS).Methods55 PCOS patients who were treated in Guangdong Provincial Maternal and Child Health Hospital from April 2018 to August 2018 were recruited as the PCOS group;46non-PCOS patients with regular menstrual cycles,normal livebird were selected as control group.PCOS pations were divided into two subgroups:the PCOS insulin resistance(PCOS-IR)group and the PCOS without insulin resistance(PCOS-NIR)group according to the homeostasis model assessment(HOMA-IR);The PCOS patients were divided into two subgroups:the high androgen group and the non-androgen group according to the multi-hair score standard(mF-G score)and serum free androgen index(FAI);The PCOS patients were divided into two subgroups:the central obesity group and the non-central obesity group ccording to Waist-to-hip ratio(WHR).The PCOS patients were divided into three subgroups:CCgenotype group,CTgenotype group,TTgenotype group;AAgenotype group,ACgenotype group,CCgenotype group;AAgenotype group,AGgenotype group,GGgenotype group respectively according to different genotypes of MTHFR C677T site,A1298C site,MTRR A66G site.Blood samples were extracted and the single nucleotide polymorphisms(SNPs)of MTHFR genes C677T,A1298C,and MTRR gene A66G were detected by fluorescent quantitative PCR.The chemiluminescence method was used to detect the levels of plasma vitamin B12,folate and homocysteine(HCY)in the two groups.SPSS software was used to analyze the differences of plasma HCY,folate,vitamin B12 levels between the two groups,and to compare the distribution of genotype frequency and allele frequency between the two groups,and to analyze the correlation combining the patient's centrtal obesity as well as endocrine,metabolic clinical data,and then analyze the interaction between MTHFR and MTRR polymorphisms.Results1.The HCY level(9.740�1.98?mol/L)in the PCOS group was significantly higher than that in the control group(8.73�2.07?mol/L),the difference was statistically significant(t=2.50,P<0.05).No statistically significant difference was found in serum vitamin B12 and folate levels between the PCOS group and the control group(t=-0.064,t=-0.105,all P>0.05).The correlation between HCY and androstenedione level in the PCOS group was analyzed by Spearman's rank correlation test,and the results showed that the HCY level was positively correlated with androstenedione leve(r=0.134,P=0.027).2.There was no statistically significant difference in plasma HCY,folate and vitamin B12 levels among patients with MTHFR C677T loci CC,CT and TT in the PCOS group(all P>0.05).In the control group,the HCY level of subjects with MTHFR C677T loci TT was higher than that of the CC and CT,and the differences between the groups were statistically significant(t=3.481,t=3.630,both P<0.05).The plasma folate levels of subjects with MTHFR C677T loci TT was lower than that of the CC,and the difference between the groups was statistically significant(t=2.169,P<0.05).No difference was observed among subjects with MTHFR C677T loci CC,CT and TT in the control group in serum vitamin B12 levels(F=0.650,P>0.05).There was no statistically difference in the levels of HCY,folate,and vitamin B12among patients with MTHFR A1298C loci AA,AC and CC and among patients with MTRR A66G loci AA,AG and GG in the PCOS group and control group(all P>0.05).3.The the wild genotype(CC)/the heterozygous mutation genotype(CT)/the homozygous mutation genotype(TT)frequencies of MTHFR C677T in PCOS group and control group were 0.582/0.364/0.555 and 0.362/0.478/0.152 respectively.The C/T allele frequencies in PCOS group and control group were 0.764/0.236 and 0.609/0.391respectively.The distribution frequency of MTHFR gene C677T allele C in the PCOS group was higher than that in the control group(X~2=5.626,P<0.05).Allele C increased the risk for PCOS by 2.077 times(95%CI:1.132-3.812).The distribution frequency of C677T CC genotype in the PCOS group was significantly higher than that in the control group(X~2=5.474,P<0.05).Compared with the TT genotype,CCgenotype was more common with an OR of 4.392(95%CI:1.005-19.196)among PCOS cases than controls.The AA/AC/CC genotype frequencies of MTHFR A1298C in PCOS group and control group were 0.473/0.436/0.091 and 0.411/0.518/0.071 respectively.The A/C allele frequencies in PCOS group and control group were 0.691/0.309 and 0.707/0.293respectively.There was no statistically significant difference in the distribution of MTHFR gene A1298C genotypes and allele frequencies between the two groups(all P>0.05).The AA/AG/GG genotype frequencies of MTRR A66G in PCOS group and control group were 0.418/0.527/0.055 and 0.543/0.391/0.065 respectively.The A/G allele frequencies in PCOS group and control group were 0.682/0.318 and 0.739/0.261respectively.There was no statistically significant difference in the distribution of MTRR A66G genotypes and allele frequencies between the two groups(all P>0.05).4.There were no statistically significant differences in the distribution frequency of the genotypes of MTHFR gene C677T,A1298C and MTRR gene A66G loci between PCOS-IR group and PCOS-NIR group and between hyperandrogenism group and non-hyperandrogenism group and between the central obesity group and the non-central obesity group(both P>0.05).5.The levels of high-density lipoprotein and low-density lipoprotein in patients with MTHRF C667T TT genotype were higher than those in CC genotype,and the difference was statistically significant(all P<0.05).There was no statistical difference in BMI,androstenedione,FAI,LH/FSH,fasting insulin,HOMA-IR,triglyceride,and total cholesterol levels among subjects with MTHFR C677T loci CC,CT and TT in the PCOS group(all P>0.05).Compared with patients with MTHFR A1298C gene AC genotype and AA genotype in the PCOS group,the differences of low-density lipoprotein levels were statistically significant(both P<0.05).Patients with CC genotype had higher triglyceride levels than those with AA and AC genotype,the differences were statistically significance(all P<0.05).There was no statistically significant differences in BMI,androstenedione,FAI,LH/FSH,fasting insulin,HOMA-IR,triglyceride,and total cholesterol levels among patients with genotypes AA,AC,and CC at MTHFR A1298C in the PCOS group(All P>0.05).There was no statistically significant differences in BMI,androstenedione,FAI,LH/FSH,fasting insulin,HOMA-IR,triglyceride,and total cholesterol levels among patients with genotypes AA,AC,and CC at MTRR A66G in the PCOS group(All P>0.05).6.There were four homozygous haplotypes of C677C-A1298A-A66A,C677C-A1298A-G66G,T667T-A1298A-A66A,and C667C-C1298C-A66A in the PCOS group and the control group,while the homozygous haplotype of C667C-C1298C-G66G only exists in the PCOS group,but not in the control group.The homozygous haplotypes of T667T-C1298C was absent from the PCOS group and control group.MTHFR C677T gene locus and A1298C gene locus interacted with each other.MTHFR A1298C gene polymorphism was not correlated with MTRR A66G gene polymorphism.The logistic regression analysis showed that there was no interaction among the distribution of MTHFR C677T,A1298C and MTRR A66G Gene polymorphism,and the combination of the three has no synergistic effect on the risk of PCOS(P>0.05).Conclusion1.There is hyper HCY in PCOS patients.2.MTHFR C677T gene polymorphism can lead to increased HCY and lower folate,while MTHFR A1298C and MTRR A66G gene polymorphisms do not affect plasma folate and HCY levels.3.MTHFR gene C677T site CC genotype can increase the risk of PCOS,allele C is a genetic susceptibility gene of PCOS.4.MTHFR C677T gene locus and A1298C gene locus interacted with each other.MTHFR A1298C gene polymorphism was not correlated with MTRR A66G gene polymorphism.There was no interaction among the distribution of MTHFR C677T,A1298C and MTRR A66G gene polymorphism,and the combination of the three has no synergistic effect on the risk of PCOS.