[Study of DNA examination in trace sample by carrier method].

OBJECTIVE: To solve the problems of DNA testing in trace sample. METHODS: Applying original carrier method to detect known trace blood DNA and to compare it with the results obtained by high effective DNA extracting method of Chelex-100. RESULTS: The carrier method not only could obtain the right STR genotype in the trace blood sample, but also was twice as sensitive as the Chelex-100 method. CONCLUSION: The carrier method could improve the DNA detection in trace sample. It is easy to operate and is much more valuable in the forensic case analysis.