#genetics studyblr

[elinalives]

This genetics exam will be the death of me, I can’t keep learning about fly larvae

I wonder how you guys do it, I just have to keep going for a few more days 😭

[reionized]

studying genetics 🧬🌱 🫧🍃🧪🥼🔬

having a deep interest in evolution - what did the creatures of the past look like?

the bright glare of a microscope, focused on a sample of chromosomes

building and learning from hundreds of incredibly intelligent physicists, chemists, and biologists before you

discoveries at incredible speeds, uniting researchers worldwide

thousands of duplications, forming a brand new organism from two cells

the dozens of pathways turning and turning to keep you healthy

studying everything from disease to heredity to synthetic biology

the small but firm bonds interlinking each nucleic acid, impermanent but ceaselessly passed on from generation to generation

[justsomegenes]

6.12.25

long day 😴

🧫 infected new cells with virus for differentiation into neurons. Fingers crossed it works this time

🧬 lots of PCR, gels, and PCR cleanups to confirm a plasmid sequence. One more experiment tomorrow then they can be sent.

🛸 all done while watching Star Trek

🍹 had a fun dinner with some professors and students in my program who helped with recruitment

[er-cryptid]

alright nerds, favorite biology (or biology-adjacent) field

had to make this new poll so there's more options

[puffycinnabunny]

If your sleep schedule is messed up enough, you can be both a night and morning person! Haha! :,)

[briteenystudy]

cafe studying with friends 🍵

[carbon-cyanide]

☆ Just Another Manic Monday ☆

Had a long lab meeting today preparing for the fall quarter to begin. Our wet lab is officially up & running and we can start doing experiments soon! After the meeting, I did some prep for an interview on one of our projects tomorrow. I'm trying not to let my nerves get me too much on that. Then I had lunch with a friend before watching the sunset over the ocean. All in all it was a pretty great day, I know the next few months will be super challenging but it's nice to remember the good days in between.

The quarter hasn't even officially started yet & I'm already exhausted 🫠

[barelyacademia]

basics of dna replication

[girl-please-study]

12/25 days of productivity

Completed practical file for tomorrow as well as notes of unit "Chromosome". I had saved some money for my friend's birthday but as I'm far away from her, I ordered food directly to her hostel, she was very thrilled 😄💕

Study Time : 2.5 hours

[archaealice]

Hello! I used to have this domain as a studyblr but since finishing my masters, I saw little point in continuing that route so I decided to start from scratch. So consider this a little introduction back into this site that feels completely strange to me despite growing up in the Tumblr golden era.

My name is Lis, I'm a PhD student in Scientific Archaeology focusing on the effects of animal domestication in Central Europe. I'm currently struggling to find a passion for a subject that I genuinely love so I'm hoping that coming back to this little corner of the internet will reignite my love for history and learning.

[justkidneying]

Why some crossbreeds work and some don't

We can breed two types of dogs together (same species), or a donkey and horse together (same genus), but you can't breed a cat and dog together (fucking obviously). But why? And why do we even want to crossbreed things in the first place?

As for the why, that's simple: hybrid vigor. Also known as heterosis, hybrid vigor is the idea that crossbreeds have better fitness (ability to survive and reproduce) than their pure bred parents. Mostly, this term is used in agriculture and animal husbandry, but I think it leads the way for an interesting discussion (and we're definitely going to get weird in this one ;)). Sometimes though, crossbreeds are shittier at certain things. Think about a camel x llama mix. They wanted it to have the six of a camel but the hair of a llama. As far as I am aware, this program was not very successful.

Genetic Basics

For every gene, you have two copies. Each of these alleles is a bit different. Some are dominant and are expressed in the phenotype (the observable characteristics of an organism), while others are recessive (but they can still be passed on). There are other types of gene expression, but I won't go into them here. One hypothesis on why hybridizing an organism gives it better fitness is due to these dominant alleles. The theory states that as a population becomes more related, more of the recessive traits are allowed to be expressed. When you introduce a new genome with dominant alleles, you can overcome the shitty recessive ones.

Crossbreeding corn and shit is really cool and interesting, but I'm not a plant scientist so I'm not going to talk about it. We're going to talk about animals instead. So crossbreeding is mostly between things that are the same species, so think of Goldendoodles and Texas Heelers. There isn't a lot of research actually showing that mutts are inherently more fit than their parents. The main thing you can overcome is inbreeding depression (like how bulldogs don't live that long). Most traits associated with inbreeding are from recessive alleles. But sometimes you actually want to inbreed if you're looking for a specific trait (like a bloodhound's nose).

Crossbreeds that Work

Now onto some more fun stuff (in my opinion). The number of chromosomes and the relation of two species will let us know if they can crossbreed. I'll give some animals and their number will be their number of chromosomes.

Dog (78) + Wolf (78) = Wolfdog (78)

Bos tarus [cow] (60) + American Bison (60) = Beefalo (60)

Horse (64) + Donkey (62) = Mule (63)

Alright, so the first example would create a wolf dog that can reproduce with another canine. They come from the same genus. Same thing with the bovines. Next, we get to the mule. Horses and donkeys are from the same genus, but they have different chromosome numbers. This means that the donkey contributes 31 chromosomes and the horse contributes 32 to the offspring (which is actually either a mule or hinny depending on who tops). The offspring will be sterile due to its shitty code. Mules are way better (imo) than horses or donkeys, and that's why a lot of people prefer them for doing work. However, you cannot say they are more biologically fit, as they cannot reproduce.

So mostly you can see that the crossbreeds are happening in animals that are of the same genus (though you can't always breed two genus members together). You can go less related than that, but I'm not a biologist, so I don't know many examples off the top of my head. One famous one is the marine iguana/land iguana hybrid from two members of the same family (family is a step above genus).

Crossbreeding in Humans

Now, onto humans. We have 46 chromosomes (22 pairs plus two sex chromosomes [X/Y]). We also happen to have our own genus (Homo), and the closest relationship we have is to chimps and bonobos. They both have 48 chromosomes. We share about 96-99% of our genetic code with chimpanzees. The difference here his chromosome number two. This is the chromosome that gives us the difference. Our #2 has the same info as two chromosomes in chimps. Therefore, it's thought that this is due to chromosomal fusion in our evolutionary history.

In saying this, I want you to know that we also share like 85% of DNA with dogs as well, because a lot of DNA is just being alive, having a spine, and being on land. Shit like that. There's not as much difference in animals as people like to believe.

We're gonna get weird now. So, there have been attempts to crossbreed chimps and humans, and they were unsuccessful (they were in the USSR). But if it is entirely out of the realm of possibility? No idea. I argued with some of my classmates about this for a while. There have been bigger jumps in crossbreeding, and I think we won't ever really get an answer to this anyway. I feel gross and I'm going to move on now.

One animal has successfully been hybridized with humans: mice. Transgenic mice have either human DNA inserted in their entire genome, or they may have it only in some cells of the body (chimerism). This is mostly to test disease and stuff, it's not as cool as it sounds, they're mostly just getting them to express things like interleukins. This has sparked debate however, about whether or not this is against nature or whatever. I think it's a dumb argument cause fuck it do whatever you want, but I believe that a lot of this sentiment will stagnate research and advancement in this field, so...

Where is the line between one species and another?

A weird note to end on: HeLa cells. These are a cell line from a woman's cervix (who died in the 1950s) that now have about 76-80 chromosomes. While they can't crossbreed in the normal way, they can fuck up other cell cultures. If another line is contaminated with them, HeLa cells will dominate and their genetic markers will be found in that of the resulting cell line. This made me circle back to the point about transgenic mice. The controversy from politicians was about where you draw the line about what is human and what is not. You can say a mouse with 1% human DNA is not human. But what about a 50% match? What about HeLa cells? Are they no longer human cells, and when would a line have been crossed? Anyways, just some food for thought. Thanks for reading my ramblings.

[justsomegenes]

6.06.25

honestly a difficult day to end a difficult week but oh well thats why i started this blog

🧫 Neuron differentiation day 4. Postdoc said a lot of the cells look dead and discussed caring for iPSCs generally, and I became stressed that I have not been culturing them correctly. sad i may have to come in on sunday for something that I'll have to repeat, but trying to remember this is just a rotation, and my first time doing this, and I am here to learn

🧪 PCR to test sequencing primers to confirm plasmid sequence, most of them seemed to work! plus realized i need a flashdrive to download my gel image

oh also my worst nightmare came true and i slapped my cells and flipped the plate while looking at them on the microscope... tbd if they survive the attack

[er-cryptid]

Completing the Lagging Strand [Diagram]

Patreon

[puffycinnabunny]

Not so aesthetic midterm notes 🍊

[larstudy]

🖥️ 28.06.2023 // It was my first day of internship at the Marie Curie Institute! I did mostly administrative tasks as trying to pick up my entry badge (I will only have it tomorrow *sob*) and code to have access to the intranet. I also read some genetic papers about a constitutional mutation on breast cancers as it's what I will be working on for the next two month! I'm so so excited to discover this field! 🩵🩵

I left my internship early to eat with some friend and have a picnic with other friends. It was so nice to see all of them after studying that much for my finals 🩷

Also, tomorrow there will be a meal with all the unit on the balcony! I can't wait for it even if I'm a bit anxious about meeting everyone in one go ahah

[carbon-cyanide]

☆ Grad school life ☆

This week has been an opportunity for me to catch up on some of my bioremediation research before diving back into the computational stuff next week.

I'm starting to see how each chapter of my dissertation is being formed by the various projects I'm engaged with and how each of those things connects to central ideas around water pollution and bioremediation.

For the first time this summer I feel like I've caught my breath and I'm excited to dive full force into lab work now that the wet lab is fully functional and cleared for experiments.

My advisor (an avid surfer) says I've got momentum & now I just gotta keep riding the wave...