Gene R and gene T are genetically linked. Answer the fol...

Question

Gene R and gene T are genetically linked. Answer the following questions concerning a dihybrid organism with the genotype Rt/rT:

If r = 0.20, give the expected frequencies of gametes produced by the dihybrid.

Accepted Answer

Welcome back everyone. Let's look at our next question. It says which of the following is a drawback of using a high number of genetic markers in linkage mapping. And the answer choices are a, it can provide false positive results. B it may prolong the processing time necessary for the A analysis C it may overin overestimate the distance between genes and D all of the above. Let's look through these answer choices. Keeping in mind that we do have a choice D all of the above as an option. So let's recall what linkage mapping is. And it is that usage of recombination frequencies to determine the arrangement and distance between genes. So what order genes are in with relation to each other and their physical distance apart on the chromosomes by looking at recombination frequencies. So the more frequent recombination occurs between the two genes, the farther apart they are, the less frequently recombination occurs, the closer together they are. So with that in mind, what would be a drawback of using a high number of genetic markers in this type of mapping choice? A says it can provide false positive results. Well, this is correct because any time you have a large uh amount of data, a large number um of markers here. In this case, the likelihood of seeing false correlations between two to make it look as if the genes are having more or less recombination between them than they actually are. The likelihood of these anomalies being due to random chance goes up, the larger the number of markers we look at. So you can have this false correlation that's actually due to chance. So that is a correct answer in terms of a drawback. But since we have that all of the above option, I'm just gonna put a little dot here to mark that it is correct but not selected. That's my answer yet. Choice B says it may prolong the processing time necessary for the analysis. Well, this is also correct because a more data resulting from using more markers obviously results in more processing time. So that is another correct answer. And since we already have two correct answers, um if I were on a test time were important, I'd go ahead and select choice D because I already have more than one correct answer. But in the interest of being thorough, let's look at our choice C which is that it may overestimate the distance between genes. Well, as we know this is also correct. Um because if you have, when you have this large number of genetic markers, recombination events happening between closely related markers may be missed. And that will result in underestimating the genetic distance between the genes since you're missing those recombination events. And that makes the genes look closer together. So that is another drawback. So what is a drawback using of using a high number of genetic markers and linkage mapping choice D? All of the above is our answer here. See you in the next video.

Gene R and gene T are genetically linked. Answer the following questions concerning a dihybrid organism with the genotype Rt/rT:

If r = 0.20, give the expected frequencies of gametes produced by the dihybrid.

Key Concepts

Genetic Linkage

Gamete Formation

Recombination Frequency

Watch next

Gene R and gene T are genetically linked. Answer the following questions concerning a dihybrid organism with the genotype Rt/rT:If r = 0.20, give the expected frequencies of gametes produced by the dihybrid.

Key Concepts

Genetic Linkage

Gamete Formation

Recombination Frequency

Watch next

Gene R and gene T are genetically linked. Answer the following questions concerning a dihybrid organism with the genotype Rt/rT:

If r = 0.20, give the expected frequencies of gametes produced by the dihybrid.