Coding region: Difference between revisions

Revision as of 16:05, 14 April 2021

Revision as of 04:23, 19 April 2021

Line 48:

There exist multiple transcription and translation mechanisms to prevent lethality due to deleterious mutations in the coding region. Such measures include [[Proofreading (biology)|proofreading]] by some [[DNA polymerase|DNA Polymerases]] during replication, [[DNA mismatch repair|mismatch repair]] following replication,<ref>DNA proofreading and repair. (n.d.). Retrieved from <nowiki>https://www.khanacademy.org/science/high-school-biology/hs-molecular-genetics/hs-discovery-and-structure-of-dna/a/dna-proofreading-and-repair</nowiki>.</ref> and the '[[Wobble hypothesis|Wobble Hypothesis]]' which describes the [[Degeneracy (biology)|degeneracy]] of the third base within an mRNA codon.<ref>Peretó J. (2011) Wobble Hypothesis (Genetics). In: Gargaud M. et al. (eds) Encyclopedia of Astrobiology. Springer, Berlin, Heidelberg</ref>

== Constrained Codingcoding Regionsregions (CCRs) ==

While it is well known that the genome of one individual can have extensive differences when compared to the genome of another, recent research has found that some coding regions are highly constrained, or resistant to mutation, between individuals of the same species. This is similar to the concept of interspecies constraint in [[Conserved sequence|conserved sequences]]. Researchers termed these highly constrained sequences constrained coding regions (CCRs), and have also discovered that such regions may be involved in [[high [[purifying selection]]. On average, there is approximately 1 protein-altering mutation every 7 coding bases, but some CCRs can have over 100 bases in sequence with no observationobserved protein-altering mutations, some without even synonymous mutations.<ref name=":0">Havrilla, J. M., Pedersen, B. S., Layer, R. M., & Quinlan, A. R. (2018). A map of constrained coding regions in the human genome. ''Nature Genetics'', 88–95. doi: 10.1101/220814</ref> These patterns of constraint between genomes may provide clues to the sources of rare [[Developmental disorder|developmental diseases]] or potentially even embryonic lethality. Clinically validated variants and [[de novo mutation]]s in CCRs have been previously linked to disorders such as [[infantile epileptic encephalopathy]], developmental delay and severe heart disease.<ref name=":0" />

== Coding Sequence Detection ==