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106,112 Subscribers


I absorbed my twin before I was born, what are the chances that I still carry her DNA?

For context this was not an identical twin, and I am a male if it matters. From what I’ve gathered this also happened relatively late in the pregnancy.

I was hoping some part of her lives on in me. At least genetically.

I know things like chimerism exist, but any attempt into finding any solid research on things like that usually lead to random results that are completely unhelpful.

From what research I’ve done, any kind of sharing of DNA is mostly found in instances of monochorionic placentation, I don’t know if this is true in my case but it happens 80% of the time with IVF so probably.

06:10 UTC


My 23andMe showed that I’m homozygous for a recessive mutation in a liver transport protein gene. How do I process this?

The SLCO1b1 gene has a mutation, rs4149056. I have two copies of that mutation.

I. Am. Spiraling. Am I going to die earlier than others because of this? What specifically is failing in my body because of this? Is this a big deal or no? What does this mean for me.

05:30 UTC


What’s the reason for why my sister and I are built so different from each other?

I’m just curious what the possible genetic reasons might be for why my sister and I are built so physically different from each other. If any at all. We’re both F btw

I’m very small, with a narrow frame, skinny and not strong.

She’s a couple inches taller than me, with a bigger, wider, stocky body type. She’s always been heavier, more muscle than me, much stronger, has bigger hands, etc and I just don’t feel like we’re similar at all lol.

Is there any genetic reason for this or just random genes to each of us from our parents?

03:45 UTC


Accuracy of the following Local Ancestry Deconvolution algorithm?

I came across this recent study detailing a local ancestry inference algorithm that's claiming to be highly accurate. I've noticed other studies use qpAdm, an algorithm with similar function. I noticed some of the ancestral inferences they got as results within the paper seem a bit "off" compared to standard ones I've seen. Can someone explain if this algorithm seems to be accurate relative to current widely used ones?

Study and Excerpt: https://www.biorxiv.org/content/10.1101/2023.09.11.557177v1.full

Local Ancestry Deconvolution with Orchestra Here, we present Orchestra (Optimal [re]combination of haplotypes to establish segmentation of a target from reference ancestries), a novel LAI algorithm, and demonstrate its superiority to other state-of-the-art LAI algorithms. We apply Orchestra to retrace the genetic history of Latin Americans, as a prime example of admixture. We next explore the relationship between 35 worldwide populations and show that Orchestra can be used to estimate genetic closeness between populations and shed light on their demographic history. Finally, we use Orchestra to detect natural selection signatures.

Orchestra consists of a two-stage pipeline: a base layer and a smoothing module (Fig. 1A). The base layer classifies genomic windows of predetermined size by generating a distance measure between the target genome and each of the reference populations. This measure, recombination distance, is the minimum number of segments needed to reconstruct a target sequence from the sequences present in each reference population. It approximates the number of crossover events needed to reconstruct a given sequence. The base layer uses a greedy approach in which a similarity matrix is calculated by an element-to-element comparison per position and per sample, to obtain a vector of recombination distances across all reference populations. The smoothing module is a deep learning model with convolutional and attention-based elements. The convolutional element processes the base layer insights generated for each window using the information from surrounding windows. The attention-based component provides a weak link to global ancestry. This is reflective of real world genomes, since the presence of a certain ancestry in one place of the genome increases the likelihood of finding that same ancestry in other genomic regions. Combining the recombination distance base layer with a deep learning smoothing module synergistically leads to a novel, state-of-the-art technique for accurate ancestry deconvolution.

The accuracy of any ancestry model greatly depends on the quality of the reference panel. We assembled a set of reference populations by merging data from more than 30 published studies, combining both whole genome sequencing and array-based genotyping (table S1). A significant fraction of the total samples comes from non-UK ancestries captured by the UK Biobank (UKBB). With much shorter migratory distances just a few decades ago, we found that tracing ancestral origins by birth-place and self-reported ethnicity of UKBB participants was a sufficiently reliable proxy for ancestry (figs. S1-3). All retrieved samples underwent a series of quality filtering steps. We kept a composite set of directly genotyped variants obtained by combining all SNPs from array-based studies and filtered by a minor allele frequency (MAF) ≥ 5% to minimize imputation-related biases (see Methods). Next we conducted two GWASs to check if each SNP was associated with a genotyping platform or ancestry, and filtered out those that ranked in the top high and low end, respectively, to minimize batch effects and retain meaningful ancestry informative differences. We then used two separate dimensionality reduction techniques to characterize relationships between samples and remove any samples that showed a disagreement between reported ancestry and inferred genetic origin: 1) Principal component analysis (PCA) followed by uniform manifold approximation and projection (UMAP) (21) and 2) t-distributed stochastic neighbor embedding (t-SNE) (22) used on genealogical nearest neighbor (GNN) statistics estimated with tsinfer (5). This resulted in a high-quality reference panel of 10,169 non-admixed individuals from 35 world regions, which we used as our reference populations (fig. S4; see table S2 for three-letter population abbreviations; see Methods for more details).

We benchmarked Orchestra against other leading LAI algorithms, including RFmix (9), Gnomix (10) and FLARE (11), using two reference panels: 1) 1KGP-16pops, a high-coverage WGS set of non-admixed and unrelated samples collected by the 1000 Genomes Project (1KGP) with 16 populations and 2) custom-35pop, our larger, more diverse curated panel with 35 populations. Both panels were split into test and training sets (20% and 80% of samples) and used to simulate 6 generations of random admixture using SLiM (23). Precision and recall were reported as performance estimates on all chromosomes per generation and per population.

Orchestra substantially outperformed other LAI methods (Fig. 1B). When using the 1KGP-16pops reference panel, Orchestra’s average recall and precision across generations was 90.17% and 90.22%, respectively; an improvement of +15.89% and +14.03% compared to the second best model, Gnomix. For the custom-35pops panel, the average recall and precision was 79.54% and 80.54%, respectively, an improvement of +15.04% and +13.99% compared to the next best model, RFmix. Orchestra was the most accurate across 6 generations of admixture. As expected, the accuracy decreased with an increasing number of generations. However Orchestra’s performance in the most admixed samples equaled or exceeded the best performance in the non-admixed generations by other LAI methods.

Orchestra retained high accuracy regardless of the reference population, with an ability to distinguish between closely related ancestries. Orchestra achieved accuracy greater than 75% for all populations within the 1KGP-16pops panel (Fig. 1C). For the custom-35pops panel, Orchestra achieved an accuracy of over 50% for all populations, and over 75% for 26 out of 35 populations. The other three LAI models struggled with a third of the populations, with accuracy below 50% (Fig. 1C). Orchestra’s accuracy was superior at both region-wide and continental levels, the recall exceeding 93.43 and 98.90% for 1KGP-16pops and 87.73% and 94.03% for custom-35pops (figs. S5-8).

In addition to our two panels, we applied all LAI models to over 10,000 UK biobank samples that were not included in the custom-35pops panel (fig. S9). Orchestra outperformed the other LAI methods for 91% of the 103 evaluated countries.

03:45 UTC


What could be the genetic purpose

Of male pattern baldness? Why did it survive genetically and become so common?

23:15 UTC


Blood types

Okay so my dad is my confimed dad and so is my mom.

Both my parents used to be blood donors and their blood types are written down.

My mom is O and my dad is AB. I am AB and i have no clue how. Ive been tested more than once and its AB. Does anyone know how? I was born with a slight birth defect in my leg but i dont think its important.

19:52 UTC


Why don’t women go bald?

I’ve seen that hereditary baldness affects up to 50% of men in their lifetime. Why is it much rarer in women?

15:27 UTC


Company to extract HMW DNA from tooth?

I have an old tooth from a deceased relative, and would like to try to have high molecular weight DNA extracted from it. Are there any companies that provide this service? I know that To The Letter DNA and SecuriGene Laboratories are two companies that extract DNA for deceased specimens, but would like to know if there are any other similar companies that can work with teeth. Thank you

05:05 UTC



So if my mom and my sisters moms are cousins. Does that mean we’re sisters and cousins at the same time?

04:35 UTC


Undergrad needs help with qPCR.

I just got this job and my grad student is extremely demeaning to me, and before you ask I was just thrown into the deep end with no float and I need this job for another month to pay for rent. I have never taken a chemistry class in my entire life so I am lost with calculation how much primer I need to add into my qPCR reactions. To be honest I have no idea what a nano molar is, I am begging anyone to please help me and show the steps.

Ordered Primers:

F: 25nmole (Need to dilute to 100uM stock how do I do this???)

R: 25nmole (Need to dilute to 100uM stock how do I do this???)

Probe: 250nM (Assuming I need to dilute to 100uM????)

qPCR mix 20ul (maybe 17?) reaction:

I dont know how much of anything to really add

Mix: 10ul????

F: Need to have 500nM per reaction

R: Need to have 500nM per reaction

Probe: Need to have 125nM per reaction

water: ????

DNA: 3ul???? (right?)

I am begging anyone to help me, please. This is simple stuff I just don't know how to do it.

1 Comment
20:57 UTC


VUS Prediction

I have a variant of uncertain significance and it is predicted/expected to disrupt the protein function of the specific gene. Does this mean that it is more than likely pathogenic?

19:49 UTC


Do blondes always carry a brown gene?

I have black hair and my whole family has black hair nothing else. If I dated someone with Blonde hair, why do online hair predictor calculators say they have a higher chance of having BROWN hair?

17:16 UTC


Career switch to genetics

Career switch to genetics

I(26F) am regretting my masters specialty. My undergraduate was in Genetics and biotechnology and I really enjoyed it, but I joined a plant biotechnology masters and now I want to switch back to genetics for a career. I still did genetic work in my masters. I have been applying for positions internationally since my country does not have many science opportunities, but I keep getting turned down for positions due to being a fresh graduate from international companies. The local opportunities are slim and my country has policies in place where white people are the last resort to hire. I really want to get some experience and get a decent job. I would study further if I got a bursary as well. I would love some advice for a fresh graduate that wants to return to genetics and hopefully emigrate in the future.

12:46 UTC


Delayed Foot Cancer?

Why can cancer take so long to manifest after a cell is damaged? For example this guy, John Groberg, received Polynesian medical treatment in his early twenties that involved exposing the bottom of his feet to the sun for multiple days in a row. Later in life he developed skin cancer... on the bottom of his feet.

The radiation from the sun would have done it's damage at the time of the excessive sun exposure. I would think that that would be the time for damaged cells to mutate, but it wasn't. Between then and his cancer diagnosis, wouldn't he have rotated through plenty of new skin cells, eliminating the original damaged cells?

Why such a long delay in getting cancer?

By the way, you can see how this guy's foot sunburning is depicted in the movie The Other Side of Heaven.

12:56 UTC


Will my daughter keep her blue eyes ?

( not a native english speaker lol)

My daughter was born with bright blue eyes that i thought would go away with time like most babies since we are both brown eyed and the vast majority of our family is too. But different healthcare providers have told us that "she looks like she 's gonna keep her blue eyes", because apparently her eye colour is very bright.

My boyfriend's grandfather has blue eyes, but only my great great grandfather had blue eyes. I thought it was too much generational gap to pass on the gene, but am I wrong ?

03:31 UTC


Are personality traits dominant/recessive?

Physical traits like blonde hair are dominant/recessive. But if someone inherits introversion from the mother and extroversion from the father, is one or the other dominant or recessive?

Also if you physically look more like one grandparent does that mean you probably have more of their personality? If you have 50% Italian ancestry and your father has an Italian father and a Dutch mother does that mean you got all the genes from your grandfather, including personality genes?

20:29 UTC


Y Chromosomes Allow Us to Trace Ancestry Back Generations

13:34 UTC


Can someone answer this please? I don't get it.

How many alleles can be detected in a cell homozygous for the ABH1 microsatellite locus after it has undergone endoduplication of the region in which the locus is located?

14:18 UTC


Have there been studies that analyzed how different human eye/hair color phenotypes increased/decreased over time (especially in Europe) ?

(First post in this sub. I read the rules, but if I forgot something, please say it immediately so I can edit my post. I hope it's the right place to ask. If not, please say where I should ask because I really wonder about this)

I was reading about eye and hair color recently, and from what I understand so far, blue eyes people in Europe have the same unique ancestor that lived about ten thousand years ago. (Note: recently it has been discovered that up to 16 genes are responsible for eye color, but this isn't really relevant for my question)

From what I learned until now, it looks like there isn't really an advantage to have blue eyes over having brown eyes (blue eyes actually tend to be more light sensitive), so the main hypothesis currently is that it was just a sexual advantage to have them (i.E. "blue eyes look attractive"), so people having them were more likely to pass on their genes, that's why blue eyes spread so much over time, from one individual ten thousand years ago, to about 10% of world population now (and much more in Europe).

This led me wondering: doesn't this obviously imply that eye/hair color phenotypes have been constantly changing in prevalence/importance, and that the share of blue eyed people in Europe has been constantly increasing over the last few thousand years ?

In other words, only one individual in Europe had blue eyes them 10 000 years ago, but now about 25-30% have them. So this phenotype definitely increased in importance.

Are there studies that analyzed this phenotoype growth/decrease in the last few centuries, especially in Europe ? For example, has the share of blue eyed people in Europe increased since Ancient Roman times (2000 years ago) or during the Middle Ages ? Did they collect DNA samples from skeletons of populations of different times in history, and found that some phenotypes became more common over time, while other decreased ?

I wondered about this question after thinking about blue eyes, but obviously this also applies to other eye colors (gray, green, hazel), hair colors (red, blonde, brown), and other types of human phenotypes.

12:43 UTC


Warrior gene: more or less neurotransmitters ?

Hi all!

I was looking into the Warrior Gene, which is linked to many psychiatric disorders, but what is unclear here is; Does this gene breackdown neurotransmitters much more or let more neurotransmitters to be existed ?

I'm really confused, there are contradicted studies. Can people here discuss about that ?

22:41 UTC


Can blood types “skip” a generation

My coworkers and i were talking about our blood types. And one coworker said he’s AB+ his Wife is A- and his son is O+. I kind of looked at him confused and asked how his son doesn’t have the same blood type as his parents. But he says his mother in law is O+ so it skipped a generation. Is this possible?

Edit: don’t worry everybody. I’m not going to tell him. He’s 70 and loves her to death. I’m not going to ruin his life. Ignorance is bliss. Poor guy.

21:51 UTC


Are all inosine base pairs considered wobble base pairing?

For instance, I:C, I:U, or I:A

20:29 UTC


A1ATD and Incomplete Dominance

If the definition of Incomplete Dominance is the following:
"Genetic phenomenon in which the distinct gene products from the two codominant alleles in a heterozygote blend to form a phenotype intermediate between those of the two homozygotes.”

And A1ATD expresses both CoDominance AND different Phenotypes according to each Allele Genotype:
"MM Genotype is Normal, SS Genotype causes moderately low levels of A1AT and ZZ Genotype causes severely low levels of A1AT."

Then why isn't A1ATD considered as an example of Incomplete Dominance?

Analyzing Thalassemia, on the other hand, we have a Condition which shows the characteristics similar to those of A1ATD, but it's considered an example of Incomplete Dominance. Why is that?

18:07 UTC


Dihydropyrimidine Dehydrogenase Deficiency Gene Mutation

I'm searching reddit because I just discovered, through gene sequencing, that I have TWO gene mutations on DPYD, variant rs1801265. That gene causes an inability to process certain by-products of metabolism and can hinder the body from detoxing chemo drugs, causing a massive reaction.

So, I'm going to go see a geneticist to talk about the chemo issue. From what I've seen in the research, I shouldn't ever do them, which is hopefully not going to be relevant anytime soon.

I've been SICK for the last ten years or so, and I have a long history of less dramatic issues, but they do include learning disabilities and muscle tone issues.

I'm trying to figure out if this mutation can be an explanation for why I've been sick.

It seems to me that they've studied babies who die pretty quickly - very sad! And adults who have no symptoms but cannot do certain chemo drugs. But I can't find anything on people who might be like me - sick but didn't die in infancy.

If anyone here has information, or a place I could go for more information, I'd love to hear your thoughts.

16:57 UTC


Can someone explain why I'm O+ but Promethease says that I should be A?

My doctor and the employee at Quest didn't want to do a blood type test. They said to go donate blood to figure that out. I'm annoyed though because I feel extreme fatigue even after getting labwork done and the amount of blood they take is miniscule compared to donating blood so I'll probably pass out. Do you know what my options are?

I had surgery and my chart said I'm type O+. So here's where I'm confused: I could have sworn my grandma had said she was type O- and my grandfather was AB+. However, according to what I've read these results shouldn't be possible.

I may be incorrect though so I asked ChatGPT about if my blood test the hospital gave me before surgery could have been inaccurate. I'm attaching a screenshot of their response. Is ChatGPT accurate?

Should I be type A like Promethease says? These were from an AncestryDNA test that I uploaded to that site. I know it's not a mixed up result because I matched with relatives on both my mom and my dad's side on Ancestry.

Does this mean I'm a weak A like what ChatGPT suspects? In which case, how do I change my hospital records when my doctors don't even want to listen to what I say because I have an anxiety disorder listed on my chart?

All of my grandparents have passed away. My parents both say they are O+, which makes sense given my my charts, but my dad says he remembers his dad being AB too and his mom being O-. I know there wasn't infidelity. So is this worth looking further into? Am I confused? Is ChatGPT incorrect? Is there a risk to leaving my chart as-is? I know nothing about this topic. This would also have to mean my dad's blood was typed incorrectly too, right? Furthermore, all 3 of my siblings are supposedly O, so what are the chances that we are all weak A types? I'm really confused. Does this even matter? It's not like I could be hurt if I got a blood transfusion, right?

06:44 UTC


MCAT DNA Replication questions

Studying for the MCAT using Uworld. Starting w/ DNA/RNA replication and genetics.

Two questions:

-Primase creates RNA primer that DNA Polymerase III uses to begin replication. Why is it called an "RNA primer" if it's used by DNA to create more DNA? Just a misnomer, or whats the logic behind calling the primer that DNA is using "RNA primer"?

-The 3' OH attacks the P on a dNTP to add it to the growing strand and connect its appropriate base (A, C, G, etc.). How does the OH attack the appropriate dNTP? Arent the Phosphate groups the same for all the different nucleotides? Only thing that looks different is the N base structure, which is not involved in the 3' OH - 5' P rxn.

14:01 UTC


Is it possible for results to vary >90% between two DNA tests of the same person?

I took a whole genome sequencing test (Sequencing) to learn more about the relationship between my health and my genes, but the ancestry report was included in my package. Given my well-documented family history and information I had learned from other family members who were interested in the ancestry side, I did not anticipate any surprises. However, the results reported less than 0.5% from the general region where both sides of my family have well documented ancestry (which I'll refer to as 'A' for simplicity). There were also many regions reported with high percentages that we have absolutely no record of. These results were so far off from what was expected that it led us to consider possibilities like receiving someone else's test results, being switched at birth, and whatnot. I am not adopted, my birth is also well documented. No matter how we looked at it, it just wasn't adding up. I am 99% sure my test was not contaminated. I was very paranoid about my sample collection.

For a 'second opinion', I took another test through 23 and me, which reported >93% 'A' ancestry, aligning with my family's records. There were other regional inconsistencies between the previous test and the second one respectively (e.g., 13% 'B' vs. 0%; 20% 'C' versus 1%; 14% 'D' vs 0%; 11% 'E' vs 0% and etc.). I understand variations can occur between tests from different companies, I understand companies analyze the data differently, I understand they have different sample sizes etc. etc. I emailed Sequencing and their response was just its normal to have variations between tests. I genuinely want to understand how it could be possible to have two DNA tests this different still belong to the same person.

Although I know my family history, this question is important to me because I need to know if the rest of the results, the information I was interested in learning in the first place, can even be trusted.

12:43 UTC


Serotonin Transporter

I have a question regarding 5-HTTLPR and the long/short variants. I’ve seen studies linking emotional reactivity/sensory sensitivity/a multitude of mental health disorders to the short variant, but also seen meta analyses that do not show any correlation. A lot of that research seems to have been conducted in the 1990s or early 2000s. I’m wondering: what is the general consensus in the field surrounding this polymorphism now? Additionally, some of these studies mention that the short variant allows for increased serotonin in the synaptic cleft. Wondering if anyone knows of anything else that could allow for this, such as a polymorphism that codes for decreased numbers of serotonin receptors?

Interested in what y’all have to say but especially interested if you’re in the field 🙂

21:22 UTC


Is a Birth Control method possible based on modifying genetics?

16:49 UTC


Genetically Optimizing Bioluminescence in Plants

Hey everyone,

are there people here studying, working in, or just interested in bioluminescent plants?

As part of my research, I am working with plants and got into bioluminescence as a side-project. Since the science is still very limited in terms of use cases (particularly due to low light intensity, working only for limited range of plant species, and short light emittance duration), I started diving into it to look for ways to improve it.

If someone is interested in this field as well, I would be happy to exchange thoughts! :)

1 Comment
12:22 UTC

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