
Heteroduplex analysis (HDA) is a method in
biochemistry used to detect
point mutations in
DNA (Deoxyribonucleic acid) since 1992.
Heteroduplex
A heteroduplex is a double-stranded ( duplex) molecule of nucleic acid originated through the genetic recombination of single complementary strands derived from ''different'' sources, such as from different homologous chromosomes or even from dif ...
es are
dsDNA molecules that have one or more mismatched pairs, on the other hand
homoduplexes are dsDNA which are perfectly paired.
This method of analysis depend up on the fact that heteroduplexes shows reduced mobility relative to the homoduplex DNA. heteroduplexes are formed between different DNA alleles.
In a mixture of wild-type and mutant amplified DNA, heteroduplexes are formed in mutant alleles and homoduplexes are formed in wild-type alleles.
There are two types of heteroduplexes based on type and extent of mutation in the DNA. Small deletions or insertion create bulge-type heteroduplexes which is stable and is verified by electron microscope.
[{{Cite journal, last1=Wang, first1=Y. H., last2=Barker, first2=P., last3=Griffith, first3=J., date=1992-03-05, title=Visualization of diagnostic heteroduplex DNAs from cystic fibrosis deletion heterozygotes provides an estimate of the kinking of DNA by bulged bases., url=http://www.jbc.org/content/267/7/4911, journal=Journal of Biological Chemistry, language=en, volume=267, issue=7, pages=4911–4915, doi=10.1016/S0021-9258(18)42917-1, issn=0021-9258, pmid=1537869, doi-access=free] Single base substitutions creates more unstable heteroduplexes called bubble-type heteroduplexes, because of low stability it is difficult to visualize in electron microscopy.
HDA is widely used for rapid screening of mutation of the 3 bp p.F508del deletion in the CFTR gene.
References
Biochemistry methods
Biochemistry
Molecular biology