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This is very clever - the X chromosome has a mechanism to shut itself down (which makes sense; otherwise cells in women would have twice as many gene products f
by bonsai_spool 6mo ago
This is very clever - the X chromosome has a mechanism to shut itself down (which makes sense; otherwise cells in women would have twice as many gene products from the X chromosome as cells from men).
The linked research report[1] uses that mechanism, Xist, to shutdown chromosome 21, the extra chromosome whose presence causes Down syndrome. In its present form, it would need to be optimized for each potential patient and is unlikely to be used as a treatment paradigm, but the biological approach is clever.
[1] https://www.pnas.org/doi/10.1073/pnas.2517953123 https://www.pnas.org/doi/10.1073/pnas.2517953123
- sheept 6mo ago> the X chromosome has a mechanism to shut itself down (which makes sense; otherwise cells in women would have twice as many gene products from the X chromosome as cells from men). You can see this visually because not the same X chromosome is deactivated in all cells: it's what gives calico cats their color (almost all of them are female).
- dreamcompiler 6mo agoHuman women have stripey skin too, but you can't see it under normal light because unlike cats, skin tone in humans is not controlled by the X chromosome. https://www.youtube.com/watch?v=BD6h-wDj7bw&t=225s https://www.youtube.com/watch?v=BD6h-wDj7bw&t=225s
- rendaw 6mo agoThat video seems to imply you can't see it under any light and the image there is pure visualization.
- krige 6mo agoAFAIR this comes up visually when infected with certain diseases.
- shevy-java 6mo agoCan you link to a scientific article? I have severe doubts about that claim made on a random youtube video. In fact, I'd go as far as to claim that the content of the words here, are not correct. This is why I think a doi link to a research paper is necessary. I don't doubt that individual cells are, of course, chimeric, but I doubt the "stripey skin" claim. That one makes zero sense. I just did a google search and this further confirms my suspicion. Thus I would like to ask for a link to a scientific article - until that happens I remain rather unconvinced.
- markburns 6mo agohttps://link.springer.com/article/10.1007/BF00273442 https://link.springer.com/article/10.1007/BF00273442 I haven’t read it but I did find this
- dreamcompiler 6mo agoI agree about the need for verification, but Veritasium videos are usually well-researched and more accurate than "random" videos. Here's one link: https://www.sciencedirect.com/science/article/abs/pii/S0738081X10001641 https://www.sciencedirect.com/science/article/abs/pii/S07380...
- bonzini 6mo agoFor a more practical example, how does this work for the daughter of a colorblind person (the colorblindness gene is on the X chromosome)? Do they have four types of cones?
- mjg59 6mo agoYes, but it's not limited to that case - there's two common variants of the green cone that respond to different wavelengths and people with two X chromosomes can have both, improving colour identification.
- bonzini 6mo agoHow does it feel to actually answer a question as a geneticist?...
- bonsai_spool 6mo ago> How does it feel to actually answer a question as a geneticist?... Genetics is complicated. If you really want to learn about this, all you need to do is search. https://www.bbc.com/future/article/20140905-the-women-with-super-human-vision https://www.bbc.com/future/article/20140905-the-women-with-s...
- mjg59 6mo agoI'm kind of late to this but for some context - bonzini knows me from a long time ago when I was still a genetics student and the joke here is that given where I am now in my career I still get to occasionally answer questions based on that background
- bonsai_spool 6mo ago> Human women have stripey skin too, but you can't see it under normal light because unlike cats, skin tone in humans is not controlled by the X chromosome. Humans have 'stripey' skin because of somatic mutations, and it's not clear that there are X-chromsome-located skin color loci. Don't believe everything you see on Youtube.
- Symmetry 6mo agoLikewise humans with heterochromatic eyes are generally women.
- bonsai_spool 6mo ago> Likewise humans with heterochromatic eyes are generally women. I haven't heard of this - where is this published? Here's a primer on eye color: https://www.ncbi.nlm.nih.gov/books/NBK574499/ https://www.ncbi.nlm.nih.gov/books/NBK574499/
- Symmetry 6mo agoI was misremembering, it's actually cats where hetrochromatic eyes is associated with females. In humans there isn't any difference.
- shevy-java 6mo agoAnd how do they ensure that only one X chromosome is inactivated? All three X chromosomes are, for the most part, equal, neglecting differences between father and mother X chromosome and changes during meiosis.
- deleted 6mo ago[deleted]
- samus 6mo agoPresumably by targeting them toward these differences.