Questions tagged [genetics]
Genetics is the branch of biology that deals with the transmission and variation of inherited characteristics.
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How frequently does recombination occur, and how long are the recombinated fragments?
I understand the mechanics of recombination, but am struggling with the 'scale'.
When two homologous chromosomes pair, roughly how many recombination events occur on average? I understand there will ...
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Change in gene frequency in generation due to genetic drift?
I was wondering if the reason was other than genetic drift. But I could not find an explanation.
Here is the question:
Consider an isolated, randomly mating population consisting of 100 individuals (...
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Can a person have different sex at cellular level?
I mean like every cell has a sex chromosome.So does a male with XY chromosomes has all the cells in all the organs inside his body of XY chromosomes only? And vice versa.....
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Is there evidence of an evolutionary strategy similar to human autism in mammals during the Pleistocene? [closed]
Edit trying to reopen this now that I am bored at work
I hoppe it is a bit more clear now. You can comment what you want if you are interested in reopenning this too.
As a geologist, I enjoy creating ...
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Relationship between TADs and supergenes
I need to investigate the architecture of supergenes. If someone is familiar with the topic (TADs and supergenes) could you please send me some links to articles covering this topic?
Already did ...
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Do multiple alleles undergo crossover?
For a reference, point 3 of this article: https://www.biologydiscussion.com/genetics/multiple-alleles/multiple-alleles-meaning-characteristics-and-examples-genes/35452
According to google Bard and ...
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How many base codes are in DNA? Two or four?
We know there are four bases found in a DNA: adenine (A), cytosine (C), guanine (G), and thymine (T). We also know that A always pairs with T and G always pairs with C. Can we say that the DNA is ...
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What is the most accurate polygenic score for Alzheimer’s disease?
To date, which polygenic score (i.e. which study) has produced the largest effect size for Alzheimer’s prediction in out-of-sample validation?
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Are there two different senses of the word 'heritability' in use?
Target Height as Predicted by Parental Heights in a Population-Based Study states:
The heritability value was taken as the regression coefficient between
final height and midparental height
Is this ...
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Why do many plasmids for Flp-mediated Flip-Excision only flanked by one FRT site on each side and not two non-homologous?
I'm trying to build some molecular gene switches into a model, and want to use both Cre and Flp. I understand how to invert gene segments with Cre, double floxing (e.g. with loxP and lox2272, like in ...
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Could the inability of adult mammals to digest lactose be partially explained by the loss of lactose-metabolizing bacteria from the microbiome?
BACKGROUND:
1. Lactase persistence
Lactase persistence is the continued activity of the lactase enzyme in adulthood, allowing the digestion of lactose in milk.
According to Wikipedia, only a small ...
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Ames Assay Confusion: Aren't the odds of spontaneous revertants too low to be able to accurately test the mutagenicity of certain compounds?
I am a student conducting a test with the Ames Assay. This assay uses a strain of bacteria that has a mutation in an amino acid synthesizing operon, which doesn't allow it to synthesize its protein. ...
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What does the term 'trait' really mean?
A trait is a characteristic shown by an organism.
For example a Tt plant would show the 'tallness' trait.
In same way sickle cell anemia carriers should show a 'normal' trait, but I found on various ...
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Can someone with albinism have red hair with very pale skin and blue eyes?
I have heard of a type of albinism that occurs in races with darker skin that can give people red hair, but in the pictures I've seen, they usually have reddish-brown hair, a medium skin tone, and ...
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Can hybrids from closely related species with similar chromosomes reproduce?
Let's say the plant Triticum monococcum which has 2 sets of 7 chromosomes when diploid and 1 set of 7 chromosomes when haploid has the genome AA. When interbred with a different species that has the ...
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Why is the codon size three, rather than four? [duplicate]
The genetic code consists of triplets, each of which (apart from the stop codons) yields an amino acid when the mRNA is translated.
But why did triplets evolve, rather than a longer or shorter codon ...
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Databases medicine and therapy - animal & human studies, technology readiness level
I am looking for some universal databases that would offer information about drugs and therapies currently in development.
The area of interest is mostly cell and gene therapy. I am looking for ...
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Inheritance of child behavior based on daily life experiences of the parent
Our brain is a large network of neurons connected with each other.Our daily experiences change how our neurons are connected.Some experiences create better connections between two neurons A and B and ...
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How to disambiguate between chromosome and chromosome pair?
Our genetic information is stored in 23 pairs of chromosomes that vary widely in size and shape. Chromosome 1 is the largest and is over three times bigger than chromosome 22.
Source: https://www.ncbi....
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Calculating pitch of B-DNA
From this question (How pitch of a DNA Helix is 3.4 nm?), I've learnt that for counting the number of axial rise for 10 base pairs in 1 helical turn to measure the pitch of B-DNA, we have to include ...
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How does positional memory in fibroblast cells work?
I have a question regarding how positional memory in fibroblasts work, specifically, where the memory comes from/how its made.
For example, the Salamander & other amphibians are able to regenerate ...
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What exactly is "Whole-genome sequencing"?
Newbie question: For few years I have seen news like “Whole-genome sequencing” is now under $1000 etc. I believed that this means all the base pairs of all chromatids in a single cell are identified ...
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What do alleles look like visually on linear DNA strands?
I've seen many textbook images of alleles on homologous chromosomes with the gene loci identified but how could this be visualised on linear DNA sequences with the bases written out? Is it that you ...
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What is a good expression vector for Salmonella enterica subsp. enterica serovar typhimurium
I am interested in expressing custom proteins in a Salmonella strain, however I am facing difficulties in finding the appropriate expression vector for it. It seems that most of the resources provide ...
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Considering Two Genes, Are There Only Two Possible Outcomes for the Four Gametes Produced After Meiosis, Regardless of Independent Assortment?
Is it true that for a single meiotic event when considering only two genes, there are only two possible genetic outcomes among the four gametes produced, regardless of whether the two genes are found ...
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Mitochondrial diseases inheritance
I've read information about mito genes inheritance but some parts are still obscure for me.
Here is the context:
Mother has a son that is affected by some mitochondrial disease and a healthy daughter. ...
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ddT-tailed TA cloning, and the fate of a double nicked plasmid in E. coli
In an undergraduate lab class on TA cloning, it was explained that ddNTPs are used as the substrate for terminal transferase when making the T overhangs of the vector. I was told this was to ensure ...
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Why is There a Necessity for Two Rounds of Cell Division and Four Daughter Cells in Meiosis
Why does meiosis involve two rounds of cell division instead of stopping after meiosis I, where each daughter cell would have one chromosome randomly selected from each pair of homologous chromosomes? ...
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How pitch of a DNA Helix is 3.4 nm?
How pitch of a DNA Helix is 3.4 nm?
In the image that I have attached, the numbers with prime represent the number of base pair and normal numbers represent the number of gap elements between two base ...
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Is it possible for a non-self antigen to NOT be recognized by the body?
The amazing diversity of antigens that the body can recognize (by virtue of T and B cells that express receptors complementary to them) is truly fascinating. The explanation mooted for this is the ...
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Is heritability just slope?
Is broad-sense heritability just the slope of the line that passes through the coordinates:
(1, The phenotypic correlation among monozygotic twins)
(0.5, The phenotypic correlation among dizygotic ...
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What is the exact definition of a "gene"?
(In this question, I'm only considering the molecular-biology notion of a gene, not the older Mendelian notion.)
Wikipedia defines a "gene" as "a sequence of nucleotides in DNA that is ...
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How long does it take for a gene to be switched on or off through the process of epigenetic expression?
I understand that in our lifetime, our experiences affect the expression of our genes. Some get switched on, while others switched off. Our experiences, diet, lifestyle etc. determines this expression ...
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Trying to find information about intraspecific allelic expression divergence in recombinant individuals due to changes in the cis regulatory regions
I am trying to find any research articles or resources that focus on differences in expression levels at the allelic level due to changes in cis regulatory regions in recombinant individuals. For ...
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What portion of the human genome is dedicated to the developement of the fetus?
I was thinking about how we don't know the function of a large portion of DNA and I thought maybe it's because it's only used during the development of the fetus
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Arguments against incest
Incest is forbidden in most countries because if there is a genetic disease in the family the child of a incestuous relationship will be at least holder of the gene of that disease. But lets say the ...
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Calculation for underlying genetic value of a phenotype given parents genetic values
What is the most accurate way to calculate a child's genetic predisposition to a phenotype, given both parents' genotypic predispositions?
Assume trait X is 50% heritable and controlled by an ...
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Are mutation rates normally distributed? If not, what are they?
On average, there are 64 mutations per generation in the human genome. Is this constant, or can we expect variation in the number of mutations?
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Preservation of citrus fruit
A decade ago [1] the possibility of using Cas9 systems to impart desirable properties to oranges seemed within reach [1]. Antifungals like Imazalil can increase shelf life of citrus but are known to ...
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What really is an allele?
My textbook says:
genes which code for a pair of contrasting traits are known as alleles.
Then that means T and t are alleles. Further, it says:
Mendel also proposed that in a true breeding, tall ...
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Are there any genetically modified GMO squash with a vine growth habit which grow back from the root?
When I cut Scottish thistles with scissors, the thistle grows back from the tap root.
When I accidentally step on squash vines, the squash vine dies.
I was wondering if genetics research has produced ...
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How random is genetic recombination?
Two parents can have a very large number of different potential offsprings, and it's common knowledge that the daughter chromosomes in meiosis are produced randomly, i.e. in crossover, the exact spots ...
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What actually causes temporal isolation
Temporal isolation is caused when members of the same species are available to reproduce at the same time. How is such a phenomenon even possible, is it caused by mutations which lead to a certain ...
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Is it possible for two fraternal twins to be completely different at the genetic level?
Given that the 46 chromosomes split evenly during meiosis, if the even pairs of the male gametes match with an even pair of the female gametes, the offsprings in theory should be carrying chromosomes ...
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How do we know that the DNA we share with other species (especially primates) isn't fully the result of transposable elements?
I recently read a couple studies that concluded the 25% of genetic similarity between cows and reptiles is actually primarily due to TEs (transposable elements) rather than common ancestry.
Here's the ...
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How is melatonin production related to proteins produced by clock genes?
I am a high school student learning about feedback mechanisms. My teacher gave an example of how proteins produced by clock genes are related to melatonin production. However, I'm confused about the ...
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Can We Determine the Cell Types Ab initio?
Is it possible to find all cell types in the human body and their respective transcriptomes by analyzing the human genome (and doing no physical experiment)?
If such a thing is possible in principle, ...
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What are the chances that parents and siblings are also carriers when a child is a carrier for autosomal recessive disorder like sickle cell disease?
I understand the inheritance pattern from parents to children for autosomal recessive disorders. Here, I am trying to calculate two probabilities when child is a carrier
Probability of parents being ...
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How similar are polyembryonic plant siblings to each other?
I successfully germinated all the seeds I found in a Yuzu fruit. From about half of the seeds there are 2 little plants growing, like in the picture. I understand this is due to the occurence of ...
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Why would GREML in GCTA treat SNP effects as random effects?
I've read many papers, but none of them gave clear answer to my question.
For example,
https://www.nature.com/articles/s41576-019-0137-z#Sec5
The univariate GREML approach can model multiple random ...
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