Recombination hotspot
Encyclopedia
Recombination hotspots are small regions in the genome of sexually reproducing organisms that exhibit highly elevated rates of meiotic recombination
. The peak recombination rate within hotspots can be hundreds or thousands of times that of the surrounding region. The PRDM9
protein is suspected to be a cause of hotspots. All hotspots so far characterized share similar morphology and are approximately 1.5 to 2.0 kb in width, which suggests a common causal process. Furthermore, recent studies have used patterns in linkage disequilibrium
to identify over 25,000 hotspots in the human genome
, suggesting that hotspots are a ubiquitous feature of the genome.
Genetic recombination
Genetic recombination is a process by which a molecule of nucleic acid is broken and then joined to a different one. Recombination can occur between similar molecules of DNA, as in homologous recombination, or dissimilar molecules, as in non-homologous end joining. Recombination is a common method...
. The peak recombination rate within hotspots can be hundreds or thousands of times that of the surrounding region. The PRDM9
PRDM9
PR domain zinc finger protein 9 is a protein that in humans is encoded by the PRDM9 gene. The protein has histone H3 trimethyltransferase activity, a KRAB domain, and a DNA-binding domain consisting of multiple tandem C2H2 zinc finger domains....
protein is suspected to be a cause of hotspots. All hotspots so far characterized share similar morphology and are approximately 1.5 to 2.0 kb in width, which suggests a common causal process. Furthermore, recent studies have used patterns in linkage disequilibrium
Linkage disequilibrium
In population genetics, linkage disequilibrium is the non-random association of alleles at two or more loci, not necessarily on the same chromosome. It is also referred to as to as gametic phase disequilibrium , or simply gametic disequilibrium...
to identify over 25,000 hotspots in the human genome
Human genome
The human genome is the genome of Homo sapiens, which is stored on 23 chromosome pairs plus the small mitochondrial DNA. 22 of the 23 chromosomes are autosomal chromosome pairs, while the remaining pair is sex-determining...
, suggesting that hotspots are a ubiquitous feature of the genome.
Further reading
- Researchers find surprising difference between human and chimp genomes "Despite 99% DNA similarity between humans and our nearest relative, chimpanzees, the locations of DNA swapping between chromosomes, known as recombination hotspots, are almost entirely different. The surprising finding is reported in a paper published [in 2005] in Science by Oxford University statisticians and US and Dutch geneticists."
- What's so hot about recombination hotspots? A primer on recombination hotspots by Jody HeyJody HeyJody Hey is an evolutionary biologist at Rutgers University. In the 1980s and 1990s he did research on natural selection and species divergence in fruit flies . More recently he has worked on the divergence of cichlid fishes from Lake Malawi, on chimpanzees and on human populations...
in PLoS Biology