What is a heteroduplex in homologous recombination?
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 different organisms.
Why does heteroduplex DNA form?
heteroduplex DNA Double-stranded DNA in which the two strands are derived from different DNA molecules. Heteroduplex DNA is formed during genetic recombination (see Holliday intermediate) and can be produced in vitro in DNA hybridization.
What can occur after repair of the mismatched bases found in heteroduplex DNA?
Correction of a mismatch in heteroduplex DNA can result in a gene conversion event, and such correction is effected by the same mismatch repair (MMR) machinery that corrects errors made during DNA replication.
What is heteroduplex rejection?
In addition to roles in MMR, Msh2-Msh6 and Msh2-Msh3 suppress recombination between closely related, but non-identical (homeologous) substrates, a process termed heteroduplex rejection (16-18).
What is a DNA heteroduplex?
Quick Reference. Double-stranded DNA in which the two strands are derived from different DNA molecules. Heteroduplex DNA is formed during genetic recombination (see Holliday intermediate) and can be produced in vitro in DNA hybridization.
How does heteroduplex analysis work?
Hetero-duplex analysis is a low-medium high-throughput SNP detection technique. During heteroduplex analysis, the target gene is PCR amplified and the amplified products are then denatured, re-annealed slowly to form four different double-stranded DNA molecules from the two alleles of the gene (Paniego et al., 2015).
Can homologous chromosomes have different alleles?
Homologous chromosomes are made up of chromosome pairs of approximately the same length, centromere position, and staining pattern, for genes with the same corresponding loci. The alleles on the homologous chromosomes may be different, resulting in different phenotypes of the same genes.
What happens with mismatch repair?
Mismatches are commonly due to tautomerization of bases during DNA replication. The damage is repaired by recognition of the deformity caused by the mismatch, determining the template and non-template strand, and excising the wrongly incorporated base and replacing it with the correct nucleotide.
How does the mismatch repair work?
Mismatch repair happens right after new DNA has been made, and its job is to remove and replace mis-paired bases (ones that were not fixed during proofreading). A DNA polymerase then replaces the missing section with correct nucleotides, and an enzyme called a DNA ligase seals the gap 2. Mismatch repair.
What proteins are involved in mismatch repair?
In humans, seven DNA mismatch repair (MMR) proteins (MLH1, MLH3, MSH2, MSH3, MSH6, PMS1 and PMS2) work coordinately in sequential steps to initiate repair of DNA mismatches.
How is heteroduplex formed?
Heteroduplexes are formed during late stages of PCR reactions when high levels of products, such as in nested PCR (N-PCR) are generated, and other reactants such as primers and functional polymerase, are depleted. They are also formed by the deliberate mixing of separately amplified reactions.