Objective:To compare the effect of three basic dyes in micromanipulation and LVPCR in order to set the ground for the choice of nucleus stain.Methods:Oral epithelium cell was stained using Haematoxylin solution

Gentian violet solution and Methylthionine chloride solution with the technique of micromanipulation and LVPCR System.Based on Gentian violet stain-method

the effect of 0.5

1

2

5 μl and 8 μl Haematoxylin solution and 2

5

8

10 μl and 15 μl Methylthionine chloride solution were compared to optimize staining condition.The staining effects of the three solutions under optimized condition were compared to define the best one.Cells stained by those solutions were captured by micromanipulators and DNA test results were compared;oral epithelium cells stained for 10

30 mins and 60 mins were captured to check the effect of staining time on final results.Results:Best staining effect was achieved by adding 2 μl Haematoxylin

0.5 μl Gentian violet or 5 μl Methylthionine chloride solution to 100 μl oral epithelium cells suspension

the nuclei being clearly distinguishable from cytoplasm.Useful rates of STR genotyping in 5 cell micromanipulation were 90%

100% and 66.7% respectively

with success rates of 20%

100% and 11.1% respectively.No negative influence was detected upon the extension of staining time using Haematoxylin and Gentian violet

while the extension of time in using Methylthionine chloride resulted in ADO

exerting negative effect on final result.Conclusion:Nuclei can be clearly stained using all the three solutions

and least negative effect on LVPCR can be detected using Gentian violet solution

making it the optimized choice.