Quantitative Genetics, Heritability, and Variances

[@sgb523]

This helps me a lot to understand the foundation of quantitative genetics, especially now we're in a remote learning setting in the university. This is a great supplemental material! Thank you, Sir Thomas!

[@rogersakatwijuka9804]

Excellent piece of work, well explained and illustrated. Thank you and more blessings to you.

[@eddylikhuleni2047]

Its been a long time not understanding this thing, but after your video i now understand it clear. You are the best teacher

[@isaiaskunz2017]

I wish my univercity professors were half as good as you are teaching. Thanks a lot

[@poleipaladra347]

Thank you for the clear explanation Mr. Mennella! I was wondering: How is variation explained by epigenetic modification accounted for?

[@joaquimsantos9425]

Great video!!!! Thanks for sharing it!

[@rounakkumar6259]

Simply explained ....&.fully clearing the concept.. thanks for the video

[@weevilknievel3200]

This was really simple and helpful, thank you!

[@ritikachatterjee1690]

Amazing video... explained in such simple manner.Really helpful 👍

[@sidi1128]

Thank you so much for this clear and concise explanation!

[@aavashshrestha5575]

Thanks a lot for making this video. Much appreciated👍👍👍

[@abozuraborish378]

thanks alot for helping us .... keep going

[@izzywang7060]

This video was a godsend, thank you for explaining variance so clearly!

[@tisaloewen7051]

this is the best video hands down on the subject on youtube

[@leinaessakalli9541]

very clear video thank you soooo much

[@nashiehun9141]

you teach so well

[@muhammetnazar1754]

You are the best TEACHER.!!! THANKS FOR YOUR GREAT GREAT LECTURES ....

[@muhammetnazar1754]

@@thomasmennella5501 sır, I am studying genetics , my professors can not explain clearly lectures , sır keep going. We need teachers like you.

[@Ice84letters]

really good video, explains very well how the genetic variants works

[@thomasmennella5501]

Thanks, Irene! Much appreciated!

[@christinalrichards]

I love this! Thanks! What about the parent offspring regression though? When you argue that the farmers focus on additive variance because its more predictable it doesn't explain why the regression approach works.

[@rub8046]

What about gene-environment interaction?

[@Hawthornphobia]

thank u so much...way better than my prof

[@parihars2849]

This is wonderful...Noone taught us like this before. U have done a wonderful job by sharing this on utube

[@thomasmennella5501]

Thank you very much. I greatly appreciate the kind words.

[@gens8094]

Nicely explained

[@kritika1315]

This video saved the day. You've explained everything with great clarity. Thank you.

[@faithfathi5992]

Do you have blog?

[@aavashadhikari9392]

help me to built a concept on different types of variance.

[@kasseecraft7230]

Thank you!

[@yohanneseshetu4268]

Hello Sir, I am Yohannes form Ethiopia, I need your help on how to calculate heritability and genetic advance for Augmented design, because only checks are repeated in the experiments. I used Proc mixed model in SAS, in the 1st run, treat as fixed and block as random.while in the 2nd run treat partitioned to test genotypes (as random) and checks (fixed) to produce BLUP. Please, sir, I need your kind guidance to estimate heritability and genetic advance to complete my experiment (it is single trial, 225 testing genotypes,with 5 check and 5 block). I hope your response is soon!

[@shwetaparmar6742]

Thankyou so much. it really helped ❤️

[@malihatunnesa3972]

Thanks a lot !

[@saikiranveldandi95]

could you please explain about negative heritability

[@ApiaryManager]

Thank you. An excellent explanation of Honeybee genetics!

[@ApiaryManager]

@@thomasmennella5501 If you are ever looking for a real world example of this being used in a haplo-diploid breeding programme, take a look at www.beebreed.eu

[@ApiaryManager]

@@thomasmennella5501 I appreciate your efforts in producing all of this material. Believe it, or not, I enjoyed your lectures so much that I went out and bought the book so I could follow along! :-D

[@ApiaryManager]

@@thomasmennella5501 I enjoyed your lectures very much. Your knowledge and enthusiasm are so infectious that it's difficult not to be interested! I'm not alone either. I see so many comments extolling your ability to convey the subject in both a simple and rational manner. Thanks again!

[@Modi2020]

Excellent work and video. I only noticed you pronounce it hetribility instead of heritability.

[@parihars2849]

Why does the book says that only the additive gentic variance is heritable type and not the dominant and epistatic variance?

[@thomasmennella5501]

It’s not that only additive genetic variance is heritable, but instead that AGV is the most useful for hereditary studies and breeding. With additive genes, each allele contributes to the phenotype additively and equally. So AA has twice as much phenotype as Aa, and aa lacks the trait. For this reason, a breeder can always deduce the genotype by looking at the phenotype. This makes additive genes the most useful for breeding - no ambiguity. But to your point, all of the variances are genetically based and therefore all are inheritable.

[@tinayang7351]

I do not understand why the dgv could be confusing for breeders. It can be very precisely viewed as well.

[@hugodelin4304]

well if you breed and A is big and a is small but all your cows are Aa they look like they are AA but arent so when the next generation comes around they are confused when some aa pop out. Sorry for broken English not first language

[@autumnclouds2094]

Great lecture thank you . Any numbers about respective percentages of role of environment / genes in human intelligence ?

[@boydhooper4080]

We should stick to the well recognised established terminology. In Biology and genetics a complex trait is controlled by many genes. It is polygenic. If it’s controlled / influenced by other factors like the environment, then it is a multifactorial trait. Don’t use the term complex trait to mean anything other than polygenic trait otherwise we’re going to have confusion.

[@hookem3768]

Please write your capital A's more legibly!

[@skepticmafia]

16:00 blue

[@skepticmafia]

17:00 blue

[@skepticmafia]

21:01 blue

[@TheCatarrh]

I see people are grateful for this video. I suppose thats good. I found it annoying with the ads and the crappy graphics. But maybe if I gave it a chance and actually listened to it, i would have found it worthwhile. Who knows.

[@rumibeatz4822]

8:02 whether you are homeless I gotta comment, or heterozygotic...

[@thomasmennella5501]

LOL. It does sound like “homeless I gotta comment”. Oh, man… 🤦‍♂️