How are genetic errors made and corrected?

Question

how are genetic errors made and corrected?

Answer 1

Genetic errors can also be mutation. They can be caused by radiation (e.g. X-rays, UV light etc.) They can also be cause in fetus' during pregnancy due to things like alcohol, nicotine and thalidomide. They cannot how ever be corrected to my knowledge.

Answer 2

Genetic errors occur by themselves.  They cannot be corrected.

Genetic 'errors' cause changes in evolution.  They can also give unwanted changes (real errors)

Answer 3

Mutation makes the error, but it is also mutation that corrects the error.

DNA recombination technology may repair the erroneous genes.

Answer 4

DNA damage occurs a number of ways:

-errors in replication by DNA polymerase

-UV radiation

-various chemical agents

-ionizing radiation

Specific agents tend to cause specific types of damage: UV light causes pyrimidine dimers, ionizing radiation causes double strand breaks.

Most errors can be corrected and there are a number of enzymes dedicated to this purpose, which continually scan the DNA looking for abnormal contortions, mismatches and other indicators of DNA damage. Single nucleotide repairs are the easiest, and double strand breaks are the hardest. If there are multiple breaks this can lead to chromosome rearrangements as the repair enzymes have no way of knowing which DNA fragments should be joined together: they'll just piece them together at random.

Alterations to DNA sequence are classified as "damage" until the cell completes one round of replication. At this point you have what is considered a mutation. To illustrate this consider a simple mismatch, for example a T is present where a C should be. On the one DNA strand you have a T, the other a G. If this DNA molecule is replicated before repair occurs the first daughter strand will have an AT at the damage site, and the other will have a CG. At this point there is no more damage-everything is matched correctly-so now you can say that mutation has occurred. In somatic cells the mutation is not heritable, but can still lead to problems, the chief risk being cancer. In germ-line cells the mutation is heritable.