Editing Southern blot (section)

==Applications==

# Southern blotting transfer may be used for homology-based cloning based on amino acid sequence of the protein product of the target gene. [[Oligonucleotide]]s are designed so that they are complementary to the target sequence. The oligonucleotides are chemically synthesized, radiolabeled, and used to screen a [[DNA library]], or other collections of cloned DNA fragments. Sequences that hybridize with the hybridization probe are further analyzed, for example, to obtain the full length sequence of the targeted gene.
# Normal chromosomal or gene rearrangement can be studied using this technique.<ref name=":0">{{Citation |last1=Glenn |first1=Gary |chapter=Chapter Five - Analysis of DNA by Southern Blotting |date=2013-01-01 |url=https://www.sciencedirect.com/science/article/pii/B9780124186873000057 |volume=529 |pages=47–63 |editor-last=Lorsch |editor-first=Jon  |publisher=Academic Press |language=en |doi=10.1016/b978-0-12-418687-3.00005-7 |access-date=2023-01-04 |last2=Andreou |first2=Lefkothea-Vasiliki|title=DNA |series=Methods in Enzymology |pmid=24011036 |isbn=9780124186873 }}</ref>
# Can be used to find similar sequences in other species or in the genome by decreasing the specificity of hybridization.<ref name=":0" />
# In a mixture having different sizes of digested DNA, it is used to identify the [[restriction fragment]] of a specific size.<ref name=":0" />
# It is useful in identifying changes that occur in genes including insertions, rearrangements, deletions, and [[point mutation]]s that affect the restriction sites.<ref name=":0" />
# Moreover it is used to identify a specific region that uses many different [[restriction enzyme]]s in a restriction mapping. Also it is used to determine which recognition site has been altered due to a [[Single-nucleotide polymorphism|single nucleotide polymorphism]] that changes a specific restriction enzyme.<ref name=":0" />
# Southern blotting can also be used to identify methylated sites in particular genes. Particularly useful are the restriction nucleases ''MspI'' and ''HpaII'', both of which recognize and cleave within the same sequence. However, ''HpaII'' requires that a C within that site be methylated, whereas ''MspI'' cleaves only DNA unmethylated at that site. Therefore, any methylated sites within a sequence analyzed with a particular probe will be cleaved by the former, but not the latter, enzyme.<ref>Biochemistry 3rd Edition, Matthews, Van Holde et al, Addison Wesley Publishing, pg 977</ref>
# Can be used in personal identification through fingerprinting, and in disease diagnosis.<ref name=":1">{{Cite web |last=Sapkota |first=Anupama |date=2021-06-03 |title=Southern Blot- Definition, Principle, Steps, Results, Applications |url=https://microbenotes.com/southern-blot/ |access-date=2023-01-04 |website=Microbe Notes |language=en-US}}</ref>