September 17



By heheals

September 17, 2020

Paul Andersen explains the concepts of genetics. He starts with a brief discussion of the nature vs. nurture debate and shows how epigenetics blurs this distinction. He explains how differentiation of cell types results from the inactivation of certain genes. He describes the three processes of epigenetics: DNA methylation, Histone acteylation and microRNA.

Intro Music Atribution
Title: I4dsong_loop_main.wav
Artist: CosmicD
Link to sound:
Creative Commons Atribution License

All images are either Public Domain or Creative Commons Attribution Licenses:
“File:DNA Methylation.jpg.” Wikipedia, the Free Encyclopedia. Accessed March 2, 2013.
“File:Earrr.JPG.” Wikipedia, the Free Encyclopedia. Accessed March 1, 2013.
“File:Epigenetic Mechanisms.jpg.” Wikipedia, the Free Encyclopedia. Accessed March 3, 2013.
“File:Hela Cells Image 3709-PH.jpg.” Wikipedia, the Free Encyclopedia. Accessed March 2, 2013.
“File:HeLa Cells Stained with Hoechst 33258.jpg.” Wikipedia, the Free Encyclopedia. Accessed March 2, 2013.
“File:MiRNA.svg.” Wikipedia, the Free Encyclopedia. Accessed March 3, 2013.
GM, Cooper. English: Histone Acetylation, January 13, 2013. Cooper GM. The Cell: A Molecular Approach. 2nd edition. Sunderland (MA): Sinauer Associates; 2000. Regulation of Transcription in Eukaryotes. Available from:
kumar35885. Simple DNA for Illustrations, n.d.
Rosa, Gilberto Santa. Beautiful Lips., March 25, 2006. originally posted to Flickr as Lips ……………DSCF6115a_picnikbw/soft.
SheLovesGhosts. Deutsch: Zentrale Heterochromie: Grüne Iris, Um Die Pupille Herum Jedoch Ein Braun-gelber Ring, March 5, 2009. Own work.



About the author

Leave a Repl​​​​​y

Your email address will not be published. Required fields are marked

  1. I love these videos! I'd like to clarify that at the end when he was talking about how if someone's parents have diabetes they are more likely to pass it on to their child, he is referring to Type 2 Diabetes.
    People who become overweight and developed Type 2 Diabetes change their epigenetics, while in Type 1 Diabetes there is nothing you can do to prevent it or induce it.

  2. There's one thing I am confused about. So if the histones are wrapped around our genes, and say you become a smoker (but no one in your family tree extending hundreds of years smoked) and the chemical tag is added to the histones to make that gene become 'expressed', does that mean that the 'smoker gene' is predetermined? In other words, will I have a 'smoking gene' by default that is turned off, but will only be turned on if I smoke?

  3. Hello Paul , I thought you might like to read this article that contains some reference to the historical perspectives of epigenetics. I also feel that some reference to prior learning for students about transcription factors as the determinants of specialization, rather than 'epigenetic' factors themselves would help students understand that although methylation etc have an effect on compaction, and hence expression, the primary driver of specialization are the regulatory pathways of transcription factors. Lastly, we need to make a clear distinction between cellular heritability within a cell line, and heritability between generations of organisms. I suggest a quick perusal of this article:

  4. Thank you! Great help to explain it to others. My MS kicks in when I eat gluten etc. I need no gluten/dairy/soy/sugar/GMO/food with a label/heated oils…take vitamins/good oils/minerals..probiotic…LDN..detoxing to be alright.

  5. oh goodness i hope someone replies before my test, but is methylation reversible or is it only irreversible? there's been videos about demethylation but none with a super clear explanation that i've understood. and i understand that methylation is what keeps one of the two x chromosomes silent in females and becoming fatal, so that makes me wonder if demthylation can ever occur to make that other x chromosome appear once again??

  6. I never understood this: If you block a gene from being expressed, what gene is expressed in it's place? Wouldn't it be a wrong one, for example heart cell instead of skin cell? Is there an alternative healthier gene? It can't be nothing. If i have, let's say, a mutated finger and i block that gene off, what would be in it's place? I think is absurd that there would be no finger.

  7. Hi Paul, I can't thank you enough for the brilliant content you put up here for free. I'm a Genetics major and every time I face a problem I know I can rely on you and Shomu's Biology for explanations. I was pretty stressed out looking through my lecture notes, and this really helped clear things up. Thank you, and much love from Malaysia <3

  8. I got a graduate certificate in clinical pathology and am now working on an MS in pharmacogenomics and I swear this guy should walk up for my diploma with me, because when I don't understand something I start here.

{"email":"Email address invalid","url":"Website address invalid","required":"Required field missing"}

Never miss a good story!

 Subscribe to our newsletter to keep up with the latest trends!