Genetics problem - genotypes and epistasis

  • Biology
  • Thread starter andydan1056
  • Start date
  • Tags
    Genetics
In summary, the poster is asking for help in solving a problem involving genotypes and phenotypes. They are unsure of which genotypes to use and how to show the genotypes and explain the F1 phenotypes and F2 ratios. They are looking for someone to show them the process.
  • #1
andydan1056
7
0
https://scontent-ord1-1.xx.fbcdn.net/hphotos-xpf1/v/t1.0-9/11695990_871019416316266_5030432296478917772_n.jpg?oh=e6514207eea2317acc509cbb8d1382b0&oe=560E6C72 1. Homework Statement

Homework Equations

The Attempt at a Solution



I'm really not sure how to solve this or where to begin. I don't know which genotypes to use (YYyy or RRrr?). The ratios are familiar to me as a result of epistasis, but I don't know how to show the genotypes (a.) or explain how the F1 phenotypes and F2 ratios are produced (b.)

Could someone show me the process? Thanks![/B]
 
Physics news on Phys.org
  • #2
You guess genotypes, work all the Punnett squares, and go with the answer whose Punnet squares predict the right phenotype ratios.
 

FAQ: Genetics problem - genotypes and epistasis

1. What is a genotype?

A genotype refers to the genetic makeup of an organism, including all of its inherited genes. It is represented by a combination of letters or symbols that represent the alleles (variants of a gene) present in an individual's DNA.

2. What is epistasis?

Epistasis is a type of gene interaction where one gene affects or masks the expression of another gene. This can result in unexpected phenotypes, as the expression of one gene is dependent on the presence or absence of another gene.

3. How do you determine genotypes in a genetics problem?

In a genetics problem, genotypes can be determined by looking at the alleles present for each gene in an individual. This can be done through genetic crosses, where the offspring's genotypes can be deduced by observing their phenotypes and knowing the genotypes of their parent organisms.

4. What is the difference between homozygous and heterozygous genotypes?

A homozygous genotype refers to having two identical alleles for a particular gene, while a heterozygous genotype refers to having two different alleles for the same gene. In genetics problems, homozygous genotypes are often represented by two of the same letters, while heterozygous genotypes are represented by two different letters.

5. Can epistasis be observed in human genetics?

Yes, epistasis can be observed in human genetics. For example, in the case of albinism, a mutation in one gene (TYR) affects the expression of another gene (OCA2), resulting in the lack of pigment in the skin, hair, and eyes. This is an example of epistasis in human genetics.

Similar threads

Replies
1
Views
4K
Replies
8
Views
3K
Replies
1
Views
6K
Replies
4
Views
3K
Replies
6
Views
15K
Replies
4
Views
7K
Replies
2
Views
3K
Back
Top