what are the kinds of mutations that can occur in our genome? are these mutations compeletely reverted by the repair mechanisms?
@aaronq @thomaster @frostbite
A mutation is a change in the nucleotide sequence of a short region of a genome. Many mutations are point mutations that replace one nucleotide with another; others involve insertion or deletion of one or a few nucleotides. Mutations result either from errors in DNA replication or from the damaging effects of mutagens, such as chemicals and radiation, which react with DNA and change the structures of individual nucleotides. All cells possess DNA-repair enzymes that attempt to minimize the number of mutations that occur. These enzymes work in two ways. Some are pre-replicative and search the DNA for nucleotides with unusual structures, these being replaced before replication occurs; others are post-replicative and check newly synthesized DNA for errors, correcting any errors that they find. A possible definition of mutation is therefore a deficiency in DNA repair.
Higher mutation rates in males are likely to be related to the greater number of germ cell divisions. In addition to very frequent simple mutations, there are several mutation classes which involve sequence exchange between allelic or nonallelic sequences, often involving repeated sequences. For example, tandemly repetitive DNA is prone to deletion/insertion polymorphism whereby different alleles vary in the number of integral copies of the tandem repeat. Such variable number of tandem repeat (VNTR) polymorphisms can occur in the case of repeated units that are very short (microsatellites); intermediate (minisatellites) or large. Different genetic mechanisms can account for VNTR polymorphism depending on the size of the repeating unit (see the following two sections). In addition, interspersed repeats can also predispose to deletions/duplications by a variety of different genetic mechanisms.
cool..so this means that every single mutation is repaired?
At the most yes
I saw this was for other people I wanted a try at answering it =) hope it help's :P
But also some of the mutations can't be repaired that's why I said "at the most"
Ty....yes it helped!!:)
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