Study On Gene Subtyping Of Treponema Pallidum In Blood Donors In Some Areas In Xinjiang

Objective: To find out the distribution of subtypes of T.pallidum in some areas in Xinjiang Uygur Autonomous Region and to provide laboratory basis for syphilis prevention and its molecular epidemiological study.Methods:To amplify Tp Nichols and the whole blood specimens by nested PCR .By modifying the parameters,we explored the most sensitive reaction conditions for nested PCR.TP DNA in 102 whole blood specimens from suspected syphilis patients was extracted by a commercial DNA extraction kit and were amplified by the nested polA PCR and routine PCR.Nested polA PCR was applied to amplify the T.pallidum DNA extracted by two kits from whole blood specimens. Positive 28 whole blood specimens screened by the nested polA PCR were amplified by the arp and the and tpr PCR analysed for the sizes of the arp gene and the RFLP of the tpr gene.Results:Only specific amplicons could be found in amplifying the T.pallidum polA by the nested polA PCR.The detection limit was about one TP DNA copy per reaction by the nested PCR methods. In the detection of 102 whole blood specimens from persons with suspected syphilis, there were significant differences among the nested PCR and routine PCR methods.No significant differences could be found in the nested PCR amplification by the two commercial DNA extraction kits .Eight positive specimens conformed by the arp and tpr PCR amplification .Six specimens were subtype 14d,two were 14a.Conclusion:. Two T.pallidum subtypes were found in some areas in Xinjiang Uygur Autonomous Region,subtype 14d and 14a respectively.