主权项 |
1. A method comprising:
a. combining DNA, a DNA ligase, a DNA polymerase, ATP, CTP, GTP, TTP, a first primer, a second primer and a prolongation template in a reaction vessel, the first primer and the prolongation template are the reverse complement of a same chromosomal strand, the first primer flanking one side of a short tandem repeat (STR) locus and the prolongation template flanking the other side of the STR locus, the second primer is the reverse complement to the prolongation template over the length of the second primer; b. performing a DNA polymerase mediated extension and a DNA ligation reaction and forming a reaction product; and c. subjecting the reaction product and an allelic ladder to capillary electrophoresis and thereby resolving the reaction product, wherein the allelic ladder comprises two or more alleles of the STR locus, each allele of the STR locus is combined with the prolongation template comprising a sequence that is the reverse complement to a sequence of at least contiguous 10 nucleotides within 100 contiguous nucleotides of the STR locus and a sequence that is not the reverse complement to a sequence of 10 or more contiguous nucleotides within 100 contiguous nucleotides of the STR locus. |