Using sickle-cell anemia as an example, describe what is meant by...

Question

Using sickle-cell anemia as an example, describe what is meant by a molecular or genetic disease. What are the similarities and dissimilarities between this type of a disorder and a disease caused by an invading microorganism?

Accepted Answer

Hi everyone. Welcome back. Let's look at our next question. It says which of the following types of mutations can affect protein synthesis. So let's look through our answer choices. Keeping in mind that choice D. Is all of the above. So we may have all of them being correct. Choice A. Is a mis sense mutation. So this would be a mutation that changes a single base pair in a way that affects it changes the amino acid coded for by the code on. So it's enough of a change that it changes the meaning of the code on, changes the amino acid it codes for. So this definitely would affect um protein synthesis. Since you actually have a change in amino acid that results then Choice B is nonsense mutation. A nonsense mutation is a premature stop coat on. So the change to the base pair affected changed the code on the code for amino acid into a stop code on before the end of the protein. So this obviously can affect protein synthesis as it can cause a truncated protein to be expressed. So this is also correct. So again, if I were moving quickly um I might just pick choice D. All the above right away. Since I've now got more than one correct answer. But for it to be thoroughly con we've got choice C silent mutation. Now this one is really tricky, really sneaky here. Um And we're kind of helped in a big way by the fact that we have this all of the above as an option and we already have two correct answers because a silent mutation is one in which there is no change to the amino acid. So you have a change in the code on a change in a base pair. But as we know sometimes a single amino acid is coded for by multiple continents. So a base pair is mutated. But the change to the code on doesn't affect the amino acid it codes for. So on first glance that would lead you to say hey wait a second. This would not affect the protein the amino acids the same. However we need to note that a question says can affect protein synthesis not just the protein shape or the protein structure. And of course we know that genes and that amino acids genes don't just specify a protein. They have regulatory functions um and other elements to them. And in fact a silent mutation that doesn't change an amino acid um can actually have an effect on the splicing of entrants and cause wrong splicing which definitely affects protein synthesis and even more dramatically it can affect the M. RNA structure. So sometimes we draw M. R. N. A. As a sort of a single line. But M. RNA actually folds and forms a sort of three D. Structure. And if you have a change in a base pair it can affect the structure of the M. R. N. A. And what this can do is cause a change to the rate at which a protein is translated which can definitely affect how it's expressed. Um If it's being expressed more slowly or more rapidly than it usually should be. So even though there's no change to the amino acid in the alphabet of the protein, um you can affect splicing and M. RNA structure in this change of a base pair due to the base pair change so that one is definitely a little tricky. And if it weren't part of it, all of the above question um it definitely might trip you up a little bit there. But again, which of the following types of mutations can affect protein synthesis. Um Choice D all of the above. MS sense nonsense and silent mutations. See you in the next video.

Struggling with Genetics?

Using sickle-cell anemia as an example, describe what is meant by a molecular or genetic disease. What are the similarities and dissimilarities between this type of a disorder and a disease caused by an invading microorganism?

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