RNase H2

Southern blot is a DNA hybridization assay used to detect a defined DNA sequence within restriction-digested or otherwise fragmented genomic DNA. The method separates DNA fragments by agarose gel electrophoresis, transfers the size-resolved DNA pattern onto a solid support, denatures the DNA to permit base pairing, and detects fragments that hybridize with a complementary labeled probe; the readout is a band, smear, or fragment-size distribution corresponding to the target sequence and its restriction-fragment context. The assay reflects sequence presence, restriction fragment length, gene copy pattern, structural rearrangement, insertion or deletion affecting restriction sites, and some repeat-length or terminal restriction fragment applications when the experimental design links the probe to those genomic features. Classic applications include Southern blot-based telomere terminal restriction fragment analysis and minisatellite-based DNA fingerprinting, which illustrate how the same