Study On Vitamin D Level And Vdr Gene Polymorphism And Their Associations With Susceptibility To Tuberculosis In Qinghai

Objectives : To analyze the VDR gene polymorphism in patients with tuberculosis in Qinghai province and to explore the relationship between VDR gene polymorphism and tuberculosis susceptibility.This paper also aims to understand the vitamin D level in TB patients,and to explore the association between vitamin D level and tuberculosis.Methods:(1)Gene polymorphism study: A total of 268 tuberculosis patients admitted to the Fourth People’s Hospital of Qinghai Province from May 2020 to December 2020 were collected as the case group,and 277 people during the same period as the control group.Four common polymorphisms(Apa I,Bsm I,Fok I and Taq I)of VDR gene were studied in clinically diagnosed TB patients and healthy controls.Genotyping was carried out using PCR-RFLP method,and the relationship between VDR gene polymorphisms and TB susceptibility was analyzed.(2)Vitamin D study: This was a case-control study,in which 208 TB patients and 216 non-TB patients were studied.Vitamin D levels in plasma were measured using ELISA and data were analyzed statistically.Results:(1)In total subjects,the frequency of AA genotype was higher in case group versus controls(13.06% vs.9.39%,P<0.05).The allele frequency of Apa I in patients with pulmonary tuberculosis was higher than the controls for the A allele(P<0.05).The frequency of AA+Aa genotype in TB patients and the controls was58.21% and 45.85%,respectively,and the difference between the groups was statistically significant(P<0.05).The difference was also observed statistically significant in Aa genotype in male patients when compared to female patients(49.24% vs 41.18%,P<0.05).The polymorphisms of Bsm I,Fok I and Taq I were not found to be associated with TB.The frequency of TT and Tt genotypes was different between adolescent patients and healthy adolescent(P<0.05).The frequency of T allele was significantly lower in TB patients than in healthy controls(91.78% vs.98.08%,P<0.05).No tt genotype was found in TB patients or the controls in the adolescents.(2)The deficiency rate of vitamin D for 208 TB patients was 11.06%,which was much higher than that in controls(3.70%)(P<0.05).The vitamin D level was(56.84±20.03)μg/L for TB patients and(70.78±30.59)μg/L for control group,the vitamin D level of TB patients was lower than that of the control group(P<0.05).The vitamin D levels in tuberculosis patients was higher than that of tuberculosis patients combined with other diseases(P<0.05).The vitamin D levels in pulmonary tuberculosis patients were found associated with age and gender(P<0.05).There was no significant difference in vitamin D levels between various genotypes among cases and controls(P>0.05).Conclusions:VDR gene displays polymorphism is related with tuberculosis,Apa I site may be associated with tuberculosis susceptibility in the general population,and Taq I site may be associated with tuberculosis prevalence in the adolescent population.Patients with tuberculosis are link to decreased vitamin D,and patients with tuberculosis are more likely to suffer from decreased or deficient vitamin D,which suggests clinicians considering the vitamin D status when treating tuberculosis patients.Vitamin D level is not linked to VDR genotypes.