Gene Mutation

Gene Mutations have several different types, so one would be a missense mutation, which is where one segment of DNA is substituted for another segment of DNA, which tells the gene to make a certain amino acid.

And if it’s a missense mutation, then it’s telling it to make the wrong amino acid.id code for an amino acid, but the wrong one and so this could mess up the chain.

Mini-test: GENE MUTATION 

Question 1: Which of the following is NOT an environmental factor of gene mutation?
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Question 2: An original DNA sequence is CTGGAATCGC. The mutated sequence is CTGTCGC. What type of genetic mutation has occurred?
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The next lesson: Genes, both lessons are included in Practice Tests.

The transcript is provided for your convenience.
You would also have a nonsense mutation where again, a segment of DNA is substituted for the wrong segment of DNA and it doesn’t code for anything. It doesn’t code for an amino acid at all and so the chain ends there and so it cuts that gene short and could affect the gene function.

You also have insertions, which is where a segment of DNA or base pair is inserted, where it doesn’t belong and it alters the arrangement of base pairs. It could cause the chain to end early, but it’s definitely going to change what the chain does and the function of that gene, that segment of DNA is going to be changed.

You have deletions as well, where a based pair is just deleted and then most likely the chain is not going function anymore and that genetic function is going to fail. There are different types of genetic mutations. You can have substitutions, where you just have this point substitution, this one area where a segment is changed. You could have insertions and then you would have to deletions. Sometimes this leads to just that one small incident and sometimes it leads to replication, where there are lots and lots of mutations, instead of just the one mutation.

Some causes for gene mutation are environmental causes, such as chemicals that you either ingest or that touch your body, radiation and ultraviolet lights, which is from the sun. If you have too much or sometimes just any amount of some of these things, especially chemicals, any amount of certain chemicals and then too much radiation or ultraviolet light can make your cells mutate. It isn’t something that happens always and it isn’t something that you can say, this will specifically happen, but these are environmental causes linked to gene mutation.

Biological causes would be errors made during mitosis and meiosis and these would be something that certain mutations that might occur in a child, whenever the two parents are creating the child. When that child is forming and mitosis and meiosis are going on, any kinds of hereditary mutations are going to be created in that offspring at that time. You can have environmental causes and biological causes for these gene mutations and then the results of the mutations.

Well, the original course of that DNA sequence is altered, so now something else is going to happen.  There could be no effect, it could just end, it could not have any effect to go with that DNA chain ends and that function isn’t carried out. Maybe it wasn’t something very important and so there is no effect on the organism. It could alter the product of the gene, so the genes product could come out differently than it was supposed to or it could prevent the gene from functioning properly or completely.

Maybe the genes product doesn’t get shipped out at all or it ships out something that was not supposed to ship out or it ships out part of something and the results can be neutral. For instance, gene mutation and your eye color, you could have brown eyes, blue eyes, green eyes and the mutation doesn’t harm you or benefits you generally, it’s just going to be a difference and so it will be a neutral mutation.

You can have harmful mutation that causes Down syndrome. You can have extra chromosomes there and that mutation causes physical and mental problems and then you can have beneficial mutation, such as that causes sickle cell disease. In the area where sickle cell disease had developed, people that have the sickle cell disease were able to fight off malaria better and so it was a survival benefit to have that mutation.

Gene mutation can be caused lots of different ways and there are a lot of different types of mutations. While most of them have little benefit or harm to us, there are some that can harm or benefit us, but genetic mutation is something that’s necessary because it’s what keeps people or other organisms evolving and becoming more and more advanced organisms.

The next lesson: Genes, both lessons are included in Practice Tests.

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