How to Calculate Heritability in Fruit Fly Bristle Number Genetics

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SUMMARY

The discussion centers on calculating heritability in fruit fly bristle number genetics, specifically using the mean bristle counts from a wild-type strain and a selected breeding sample. The heritability (H²) can be derived from the variance components using the equation H² = Vg / Vp, where Vg represents genetic variance and Vp represents phenotypic variance. Participants emphasized the importance of reviewing textbook definitions and specific equations related to response to selection for accurate calculations. Resources such as the NDSU quantitative genetics guide and WOU slides were recommended for further understanding.

PREREQUISITES
  • Understanding of quantitative genetics principles
  • Familiarity with genetic variance components (Va, Vd, Vi)
  • Knowledge of heritability calculations (H² and h²)
  • Basic proficiency in interpreting genetic data and equations
NEXT STEPS
  • Review the textbook section on calculating heritability from response to selection
  • Study the NDSU quantitative genetics guide on heritability
  • Examine slides #13-14 from the WOU quantitative genetics presentation
  • Practice applying heritability equations to different genetic traits
USEFUL FOR

Geneticists, biology students, and researchers interested in quantitative genetics and heritability calculations in model organisms like fruit flies.

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Homework Statement


A geneticist studying the number of bristles on the second leg of fruit flies determined that a wild-type strain has a mean number of 486.3 bristles per leg. A sample of males and females from this population with 420.0 bristles were bred and the offspring had a mean bristle number of 432.0

a) what is the heritability of bristle number?

b) if you were to select a group of flies with 500.0 bristles and breed them, what would be the mean bristle number in the progeny?

c) If we wished to generate a population of flies that had a mean leg bristle number of 450.0, what parents should we select?

Homework Equations



Vp = Va + Vd + Vi + Ve + V(g)(e)

Vg = Va + Vd + Vi

H^2 = Vg / Vp

h^2 = Va / Vp

The Attempt at a Solution



I honestly don't even know where to begin. I have tried contemplating for 20 minutes on what to freaken do and I'm getting very frustrated. If someone could PLEASE at least point me in the right direction (I get it if you don't want to solve it) then I would really appreciate the help. My teacher is no good.

Thank you very much
 
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This is some kind of quantitative genetics I have no acquaintance with and I don't know if anyone who has will be along.
I don't know what any of the symbols in your equations are.

But I recognize a pattern of question which we get about pH buffers, resistive circuits, stoichiometry, and other standard subjects.

That is there is a textbook definition and the student is asked to apply it calculating something. That is question (a). The definition of herediBlity is surely in your textbook and sufficient relevant data in your question.

We might or might not be able to help with the others if you posted a relevant Page or two from the book here.
 
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The equations you should use are not among those listed in the first post (those are a more general definition of heritability, but are not the right ones for the particular experiment you describe). You should review the relevant part of your textbook on calculating heritability from the response to selection. (Alternatively, read https://www.ndsu.edu/pubweb/~mcclean/plsc431/quantgen/qgen7.htm or take a look at slides #13-14 from http://www.wou.edu/~guralnl/311Quantitative Genetics.pdf).

Once you've reviewed that material, try posting your thoughts and we can tell you whether you're on the right track.
 
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epenguin said:
This is some kind of quantitative genetics I have no acquaintance with and I don't know if anyone who has will be along.
I don't know what any of the symbols in your equations are.

But I recognize a pattern of question which we get about pH buffers, resistive circuits, stoichiometry, and other standard subjects.

That is there is a textbook definition and the student is asked to apply it calculating something. That is question (a). The definition of herediBlity is surely in your textbook and sufficient relevant data in your question.

We might or might not be able to help with the others if you posted a relevant Page or two from the book here.

Yes I've looked at the definition and it confuses me, but I will try to look for other equations to use
Thank you!
 
Ygggdrasil said:
The equations you should use are not among those listed in the first post (those are a more general definition of heritability, but are not the right ones for the particular experiment you describe). You should review the relevant part of your textbook on calculating heritability from the response to selection. (Alternatively, read https://www.ndsu.edu/pubweb/~mcclean/plsc431/quantgen/qgen7.htm or take a look at slides #13-14 from http://www.wou.edu/~guralnl/311Quantitative Genetics.pdf).

Once you've reviewed that material, try posting your thoughts and we can tell you whether you're on the right track.

Thank you very much, I will review those now as well as look for different equations!