Genetics is the branch of biology that deals with the transmission and variation of inherited characteristics, particularly chromosomes and DNA.
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How can a three-base codon evolve from a two-base codon?
Inspired by this question among others.
It's widely suggested that the current 3-base codon system of encoding protein sequences in DNA evolved from an earlier 2-base codon system. This makes sense ...
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4answers
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Why 20 amino acids instead of 64?
This question got me thinking about amino acids and the ambiguity in the genetic code. With 4 nucleotides in RNA and 3 per codon, there are 64 codons. However, these 64 codons only code for 20 amino ...
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3answers
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What is the inbreeding coefficient for the female offspring of a sib-mating in a haplodiploid system?
The inbreeding coefficient of a sibling mating for a diploid organism is 0.25 (each allele has a 25% of being identical by descent in the offspring).
In haplodiploid organisms, males result from ...
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2answers
216 views
Smallest viable reproducing population
What is the smallest viable reproducing population, such as in a human population. By viable I mean a population which keeps genetic defects low (enough).
A very strongly related question: what is ...
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Are homozygous carriers of the CCR5-Δ32 allele fully immune to all known strains of HIV?
Or is there documented evidence of even one homozygous carrier contracting HIV and staying infected?
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1answer
158 views
How are epigenetic marks transmitted during cell division?
As far as I know, this is one of the biggest questions in the epigenetic field: how are the epigenetic marks like histone modifications propagated through cell division? A lot is already known about ...
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1answer
42 views
Historical recovery from mass extinction events
Is there a way to generally characterize how species "regrew" after the various mass extinction events happening periodically from 450 Ma to 65 Ma. Would the surviving species just start back where ...
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What kind of event would cause the current Mitochondrial Eve to be replaced by a new one?
Apparently all living humans are matrilineal descendants of a single woman who lived 200.000 years ago. She is called Mitochondrial Eve.
But at the time she lived there was a different matrilineal ...
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1answer
139 views
Chromosome 2 fusion?
I read this article by Jeffrey Tomkins and Jerry Bergman claiming to debunk chromosome 2 fusion. Is there anything wrong with these conclusions?
" 1.The reputed fusion site is located in a ...
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1answer
50 views
Why Can't A Male Mule Have Offspring?
I've read that female mules can sometimes have offspring, but that male mules are incapable of doing so. Why is that the case? Is their sperm not capable of entering the egg or is their a genetic ...
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3answers
80 views
How to map the Gene name to its Gene Symbol?
I am learning in Gene data lately so I apologize for the silly questions in advance. I read a paper for a cancer on human which found some important genes. For example, the paper listed one of genes ...
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1answer
116 views
How many people are required to maintain genetic diversity?
Imagine humans were to colonize a distant planet and it was a single one-way trip. How many people would they need to bring?
Obviously 2 is the minimum, but that would result in a lot of inbreeding.
...
3
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1answer
69 views
How does a tiger have stripes?
A vague question, but let me try to explain. My friend explained to me that in females, some cells use one X chromosome, while all others use the other X chromosome. This can result in some ...
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1answer
647 views
What is the function of the RNA primer in DNA replication?
During DNA replication, RNA primase puts an RNA primer in the lagging strand. What is the function of this RNA primer? Why can't the enzymes put DNA fragments directly?
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4answers
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Does the DNA sequence of a butterfly match that of the caterpillar it used to be?
Just had this thought occur to me.
If one were to take a DNA sample(or is it RNA?) of a caterpillar before it became a chrysalis, and attempt to match the sample against one taken after the chrysalis ...
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2answers
401 views
What are the advantages and disadvantages of using beta-galactosidase compared to luciferase as a reporter gene?
In the University labs, we have used Beta-galactosidase as a reporter gene to quantify the expression initiated by the stress-response promoter in yeast. This was done by exposing one of the two ...
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1answer
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Do antisense transcripts have different names than their sense strand transcripts?
I want to find which genes in the human genome can potentially be complementary to a transcript that could act as antisense transcript inhibtion? Are cis-NATs (naturally occuring anti-sense ...
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1answer
68 views
Bicoid regulation of hunchback
I'm learning about development via the example of Drosophila embryogenesis. I understand that bicoid regulates hunchback, among other genes. My question whether the regulation is direct or indirect? ...
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1answer
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Have there been any experiments that duplicate chromosome copies from 23*2 to 23*3 or 23*4?
Deinococcus radiodurans is an amazing bacterium with a fantastic survival rate. It can survive to high doses of radiation, in a complete vacuum and in hydrochloric acid.
How does this bacterium ...
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3answers
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Do we get 1/4 of our genes from each grandparent?
I know that we get half of our genes from each parent, but does it necessarily mean we get 1/4 of our genes from each grandparent? Or is it possible that we might get say 30% from one grandparent, 20% ...
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2answers
160 views
Difference between mice and rats
What is the actual biological difference between mice and rats? Are they actually the same thing with two different names depending on appearance (are they all mice for instance and we call the larger ...
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2answers
235 views
Which bacteria have the highest mutation rate?
From my reading on M. tuberculosis, I know that this organism has a pretty high mutation rate due to uncorrected sloppy replication, which leads to a high rate of development of spontaneous resistance ...
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1answer
92 views
What is the difference between xDNA and yDNA?
Wikipedia states that:
xDNA contains expanded bases, in which a benzene ring has been added, which may pair with canon bases, resulting in four possible base-pairs (8 bases:xA-T,xT-A,xC-G,xG-C, 16 ...
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Can genetically modified genes jump to bacteria in the eater's intestine?
The Guardian ran an article a while back talking about GM gene's jumping to bacteria in an eater's intestine. Has other research confirmed this phenomenon?
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1answer
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Have there been attempts to identify Chomsky's “language mutation” in humans?
I'm not versed in either biology or linguistics so please forgive any naiveties I may commit.
I've learned that Noam Chomsky thinks that language is a result of a single genetic mutation in humans. ...
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1answer
90 views
What determines the colors and patterns of a clam shell?
Earlier this week I was looking at some bivalve shells that had ornate patterns which ranged in color from a light orange-pink to a deep orange-red. Here is an image I found online that seems to be of ...
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What do breeders call the effect when a breed resists modification?
It is impossible to breed a blue rose or a cat with a bulldog shape. This is because breeding is limited by gene variations in the population.
What do breeders call this effect?
UPDATE
I guess ...
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472 views
What determines testosterone exposure in womb, baby's genetics or mom's body?
I read this article which has the following quote:
The ratio between index and ring finger is believed to be linked to exposure to the male hormone testosterone in the womb.
And I wonder what ...
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5answers
711 views
Difference between genetic engineering and synthetic biology
I've recently seen the term synthetic biology being used to describe research involving genetic modification of organisms. What is the difference between synthetic biology and genetic engineering?
Is ...
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1answer
563 views
What is the smallest number of amino acids required for life?
Is there any hypothesis on the minimum number of amino acids required for life?
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2answers
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How are Genetic Circuits Modelled?
I've read a recent Nature Methods paper by Moon T.S. et al, in which a synthetic genetic circuit consisting of layered logic gates was created. For example, the paper, a circuit is modelled in Figure ...
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1answer
199 views
Genetic engineering for insulin production
In order to put human DNA inside a bacteria in order to have it create Insulin, from what type of cell would you need to take the gene for insulin?
I thought it should be from any somatic cell, since ...
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0answers
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why genetics R&D advances so slowly? [closed]
I'm aware this question may sound stupid but I'm wondering why the research & development in genetics is advancing so slowly compared with the IT world. Is it a problem of funding , ethics, ...
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1answer
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Mutation in axillary buds of trees overcoming self-incompatability?
I seem to recall from either reading or lecture that there have been instances of trees that are self-incompatible accumulating enough mutations in an axillary bud that the resulting branch was able ...
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1answer
139 views
Why is offspring of identical twins not identical?
When identical twins marry identical twins, the children of the couples will be full genetic siblings but why are they not genetically identical?
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How are there multiple varieties of the potato?
The potato appears to propagate by growing an 'eye'/'bud' which eventually grows into a new plant. So there would probably be single representative of the potato species in the world with all others ...
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1answer
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methods for targetted deletion of genomic regions?
I would like to know what are currently used methods for targeted deletion of genomic regions in mammalian organisms or cell lines. I have heard of Zinc-Finger nucleases as a recent genetic ...
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2answers
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Can an adult without genetic lactase persistence still develop a tolerance for dairy foods?
While investigating the rise of adult lactose tolerance, I came across the news that China has been encouraging its citizens to drink more milk, even though most of the Asian population lacks the SNP ...
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2answers
60 views
Microbiome Data
How is it possible to access microbiome data like that found here? I'd like to perform analyses on similar type of data, but cannot find OTU data like that at the Human Biome Project. Thanks for any ...
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1answer
161 views
Does DNA contain information beyond protein synthesis?
It's well known that genetic information is stored in DNA. As far as I know, DNA only has information at the protein level. What about higher levels, such as organelles, cells, tissue, organs? Is ...
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1answer
60 views
How can GMO contaminate biologic plants?
Let consider two use cases :
I am the only farmer within a 200km radius. I first grow GMO plants. A few cycles later I decide to grow bio plants, so I uproot all of the GMO plants and plant fresh ...
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1answer
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How do members of cryptic species know who to mate with?
According to Wikipedia:
In biology, a cryptic species complex is a group of species which
satisfy the biological definition of species—that is, they are
reproductively isolated from each ...
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1answer
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How does sex differentiation work in Paracerceis sculpta, the sexually tetramorphic isopod?
Paracerceis sculpta is a marine isopod species known for its unusual reproductive strategy:
female: medium-sized; lives in harems run by an α male
α male: large; keeps a harem of females
β male: ...
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0answers
82 views
How does a plant decide when to grow a branch?
As a plant grows, at some point the first branch forms. As it continues, branches grow new branches, and so on, in a seemingly random way. Is it random, or is it driven by the environment (heat or ...
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4answers
250 views
How are the boundaries of a gene determined?
What statistical processes and methods are used by geneticists/molecular biologists to know where one gene starts and one ends?
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3answers
74 views
Is DNA mutation locally energetically stabilizing the DNA molecule
I am no biologist, but as a physicist, a spontaneous mutation (seen as a chemical transformation) should lower the energy of the system, at least locally. So I wonder if any research has been done ...
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1answer
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Phenotypic Variation of cattle - looking for academic sources
Can someone please point me in the direction of a good academic article on the following:
What are possible sources of phenotypic variation of different 400 day weights of cattle?
Furthermore how ...
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1answer
157 views
What is the functional and structural distinction between core (H2A, H2B, H3,H4) and linker(H1/H5) histones?
Many explanations of histone biochemistry isn't quite elucidating for the undergraduate student. How does histone structure (dimers, octomers) relate to their specific functions as core or linker ...
3
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0answers
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Terminology question: the scope of an allele in an organism
Let us consider a gene FOO with novel type foo.
If I were discussing an organism that has inherited foo in every cell during classical zygote formation, then I would ordinarily just say that the ...
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What is a focal copy number variation?
Often, genetics studies, especially genome wide ones, talk about "focal copy number variations" in genes or regions of the chromosome. I know what a copy number variation is. What does "focal" mean, ...
