Genetics is the branch of biology that deals with the transmission and variation of inherited characteristics, particularly chromosomes and DNA.
1
vote
2answers
18 views
Is there any source for raw data of SNP genotype frequency?
On sites like SNPedia, some pages contain the frequency of the SNP in question in different populations, based on published research. I'm trying to write a script that takes 23andme data and compares ...
4
votes
1answer
48 views
What is the minimum population size that Hardy-Weinberg calculations can be applied to?
I'm trying to find out if a particular allele is in Hardy-Weinberg disequilibrium, but the data is poor. What's the minimum population number that you can use to get any sort of respectable ...
1
vote
1answer
22 views
Mapping a mutation to known SNP, 3' UTR, miR
I've parsed out a very large TCGA cancer ssm (single mutation file) file to give me the essential information.
The ssm is in the following format:
...
1
vote
2answers
20 views
How did the activities of protocells become inheritable?
I have learned that first a protocell came to exist and its characteristics came to be passed on by genetic material. So how come genes for all the activities come to incorporate into genetic ...
2
votes
2answers
42 views
Primer design for Gibson assembly
I'm trying to design a primer for Gibson assembly. My gene of interest is on a plasmid, and I want to copy that gene, and put it into a different plasmid.
I am unsure how to design my primers for ...
0
votes
1answer
51 views
TCGA data, and bioinformatics design questions for SNP/ mirna analysis
It's my first time posting to this forum but was looking for some help on the data aspects of this project.
My tools of choice would be in python/R .
Goal: I'm looking to create a disease specific ...
2
votes
3answers
60 views
Knockdown of long noncoding RNA (lncRNA) - how is it done?
I don't work at the wet lab and don't know all the details about the knockdown techniques.
My question is:
How lncRNA knockdown is done?
For example - you have lncRNA that is functional in the ...
1
vote
1answer
24 views
What is solid-phase bridge amplification?
During Illumina sequencing there is a step called bridge amplification by which DNA is amplified by isothermal enzymes. What is this stage, and how does it work?
3
votes
1answer
51 views
What's the difference between shotgun sequencing and clone based sequencing?
What are the main differences between shotgun sequencing and clone based sequencing?
6
votes
1answer
61 views
How is the exogenous DNA protected from degradation during bacterial transformation?
During transformation, a bacterium can take up DNA from its environment. A small fraction of bacterial species are known to be naturally competent, meaning that they can engage in this sort of ...
2
votes
2answers
40 views
DNA replication Okazaki fragments
I understand multiple origin bubbles; DNA polymerase only synthesizes DNA from 5' to 3' and all that. But what I don't understand is why it has to be in fragments. Yes, DNA is anti parallel, and so ...
1
vote
2answers
41 views
Which X-Y chromosomes have the developmental genes for mammals?
I know that for a given mammal, half the chromosomes come from father and half from mother. This is typically denoted as x-y. I've recently read about "toolkit" genes that control how a cell develops ...
3
votes
1answer
31 views
What is an epistasis group?
I have been trying to wrap my head around the concept of epistasis for a couple of days now, and I think I understand it, at least at a basic level, but I still don't understand some of the ways that ...
6
votes
2answers
123 views
Effect of single-gene overexpression in the cell's response
Which are the factors that modify the overall gene differential expression by introducing a vector for single-gene overexpression?
If you overexpress a gene for a protein involved in signal ...
2
votes
4answers
69 views
Are there more descriptive ways of naming genes and gene interactions?
I couldn't help but notice just how non-descriptive the gene names that modern genetics is using. Currently I'm reading "The new science of Evo Devo" by Sean B. Carroll and here are some examples of ...
3
votes
2answers
50 views
Detecting Introns and Exons
I know that when RNA is transcribed from the original strand of DNA it contains introns and exons, and that the introns are spliced out of the strand to provide genetic diversity. However, what I ...
2
votes
2answers
77 views
Can a new Y-chromosome be created?
The major gene of the Y-chromosome is SRY. Would it be possible to get the X-chromosome and add SRY to create a "fuller" Y-chromosome?
What advantage does the skinny Y-chromosome give an individual ...
1
vote
1answer
33 views
Low complexity region and relaxed selection
I'm reading a text (Wagner, 2007) on identifying positive selection. In paper, the author says that low complexity regions are known to be associated with relaxed selection. I'm trying to understand ...
11
votes
4answers
1k views
Do white Australians have a distinct look?
Background
I've heard from many people working in tourism or similar industries that, white Australians can be recognized as Australian solely by their facial features. Being Australian myself I've ...
4
votes
2answers
84 views
How is gene expression estimated?
I'm reading this fantastic article on estimating body time: Molecular-timetable methods for detection of body
time and rhythm disorders from single-time-point
genome-wide expression profiles and one ...
4
votes
1answer
72 views
How do mutations come to be shared by all cells?
It's my understanding that various hazards can damage the DNA in our cells, causing mutations.
But whenever I picture this, I see the damage being done to one of our tissues (for example, our lungs ...
2
votes
1answer
42 views
What is the mechanism of regulation of PER /CRY genes?
I've read multiple descriptions of biological/circadian clocks and they all mention PER, CRY and CLOCK genes. While I kinda get how they are connected, what interests me is how these actually regulate ...
2
votes
1answer
51 views
Hardy-Weinberg Equilibrium: To compute probability of finding two siblings (random mating)
I've been working a little with M. G. Bulmer's Principles of Statistics (Dover, 1979) and cannot see how to properly compute half of one question. This should be a basic probability computation, but I ...
3
votes
1answer
69 views
Results of a complete DNA sequencing - are they 100% reusable?
Is that correct that a complete DNA sequencing (the whole genome) need only to be done once (per person)?
After that is done, it the complete genome can be stored and once the new genes (and they ...
13
votes
4answers
649 views
Can two humans with 44 chromosomes produce viable offspring?
It is known that there are very few individuals having 44 chromosomes, not the usual 46 chromosomes.
One example is a male in China: the first article, the second article.
The other is a female in ...
1
vote
1answer
55 views
Two brown-haired people have two children, P and Q. P has blond hair. Q has brown hair. What is the probability that Q is heterozygous?
Two brown-haired people have two children, P and Q. P has blond hair. We therefore believe that each parent is heterozygous and that blond hair is a recessive trait.
Q has brown hair. What is the ...
3
votes
1answer
46 views
What factors govern the variable age of onset in Huntington's Disease?
"Huntington's disease (HD) is a neurodegenerative genetic disorder that affects muscle coordination and leads to cognitive decline and psychiatric problems." As we all know, this genetic disease ...
3
votes
0answers
38 views
What are polytene bands, and why are they there?
Drosophila polytene chromosomes have been particularly useful in genetic research, as it made cytogenetic gene mapping possible with very little effort. This was primarily accomplished due to polytene ...
16
votes
2answers
2k views
What is the advantage of circular DNA in bacteria?
From what I understand, bacteria have circular DNA. What advantages does it have over linear strands like for eukaryotes?
Do there exist bacteria with more than one ring of DNA?
7
votes
3answers
128 views
Mathematical Modelling of Natural Selection
I'm a math undergrad looking for some papers on modelling the process of natural selection. The only paper I've been able to find is by the pre-eminent mathematician Herbert Wilf from 2010,
There's ...
6
votes
4answers
160 views
Chromosomes are of different size but why do all chromosomes have similar GC percentage?
When I browsed NCBI I saw a pattern: even if the chromosome sizes, number of genes, and number of proteins are different, GC% in chromosomes tend to be similar. The examples are linked below.
Yeast,
...
10
votes
2answers
153 views
Have any genetically altered organisms actually become abundant in a natural environment?
Most of the things that come up in Google and Google Scholar for this question have a mostly/completely speculative tone, or at best use models instead of measurements. This report describes some ...
5
votes
1answer
55 views
Are there eukaryotes without introns?
This question on the function of introns in eukaryotic genes made me think: I know that more basal organisms have smaller introns and fewer alternatively spliced exons compared to mammals. But are ...
0
votes
1answer
22 views
Definition of Dye- Reduction Test?
Can some one give a simple explanation or definition on what a dye-reduction test is.
1
vote
1answer
46 views
How are geneticists able to isolate gene functions?
As an example, this Scientific American article describes a known area in the dog genome that metabolizes carbohydrates.
How is it that researchers are able to determine specific functions such as ...
1
vote
0answers
39 views
Can mammals from different species reproduce?
I'm curious on how genetically different can two animals be in order to reproduce. Could they belong to different species?
One example is the mule which is the offspring of a donkey and a horse, in ...
2
votes
1answer
36 views
What's the difference between a free chromosome fragment and an extrachromosomal array?
This is reference to a review on C. elegans mosaic analysis by Yochem and Herman, in which the authors make a distinction between free chromosome fragments and extrachromosomal arrays.
For the ...
4
votes
1answer
98 views
What is the biological mechanism underlying caffeine intolerance? (CYP1A2 or other?)
As far as I can tell, caffeine metabolism occurs primarily via the CYP1A2 enzyme. I am curious as to whether mutations in the CYP1A2 gene are associated with caffeine intolerance. Some site that is ...
0
votes
0answers
26 views
Recombination-based vs. Sequence-based genetic mapping
Now that sequencing is becoming increasingly cheap, what is the value of recombination-based genetic mapping against the sequence-based genetic mapping?
I think that in the past recombination-based ...
0
votes
1answer
77 views
How many nucleotide pairs code one gene?
As I know three nucleotide pairs (triplus) code one gene. But I have found next information in the "Molecular biology of the cell" by Bruce Alberts:
Mycoplasma genitalium: it has only about 480 ...
6
votes
1answer
63 views
Are all chromosomes equally susceptible to mutation?
The humans have been around for a few million years, other organisms longer yet. Changes that occur in the genome and propagate (may) eventually throw a new species ... or atleast branch off the old ...
7
votes
1answer
64 views
What causes XYY Syndrome?
It's obvious how a misdisjunction can result in klinefelter's syndrome (XXY) but I don't see how this can result in XYY syndrome. Your parents have a collective total of only one Y chromosome so how ...
7
votes
2answers
154 views
What makes a gene dominant or recessive
We all carry two copies of each gene (outside of male sex chromosomes). If the two differ from each other often one is dominant and one recessive. How does this mechanism work on a molecular level? ...
3
votes
3answers
39 views
When can I assume individuals marrying into a pedigree are non-carriers?
If I'm not told that they're non carriers, and if I don't have proof of their geneotype based off of progeny, when can I assume they're non carriers for a trait?
7
votes
2answers
214 views
Why doesn't recombination occur in male Drosophila?
"Males do not show meiotic recombination, facilitating genetic studies."
For a while I have known that this phenomenon occurs, this quote comes from the Wikipedia page on Drosophila melanogaster, ...
4
votes
2answers
85 views
Hershey and Chase experiment
http://www.youtube.com/watch?v=3QJ4CjFsflA
This is a link to Hershey and Chase experiment. According to this experiment, we conclude that DNA is the genetic material. But how do we conclude that DNA ...
1
vote
1answer
57 views
How do circulating androgens contribute to higher rates of hirsuteness in some women?
I was reading up on ethnic groups in which the women are naturally more hirsute (such as South Asian women) in the context of evolving standards of beauty. I came across this statement on a forum:
...
10
votes
3answers
221 views
Athletes: nature vs. nurture?
Having watched a lot of olympians the last few weeks, I was struck by how many of them have actually spent their wholes lives/careers training for their one event (be in running a marathon, or ...
7
votes
0answers
59 views
paralogue genes in genome-wide association studies?
Has anybody tested if there is an over-representation of significant paralogous copies of genes -- either tandemly-arranged or in different chromosomes -- in the list of significantly associated genes ...
4
votes
3answers
749 views
Is the theory of evolution being disproved by bats?
For some species the Darwin's theory evolution makes perfect sense. I can easily imagine how, for example, the giraffe has evolved to its current appearance: the natural selection was favoring ...
