Genetics is the branch of biology that deals with the transmission and variation of inherited characteristics.

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Heterozygosity under genetic drift

The wright-Fisher model of genetic drift is: $$p_{ij} = \binom{2N}{j}\left(\frac{i}{2N}\right)^j \left(1- \frac{i}{2N}\right)^{2N-j} $$ ,where $\binom{2N}{j}$ is a binomial coefficient. From this ...
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1answer
189 views

Troubleshooting for Agarose Gel Electrophoresis

SI ran my 2% agarose gel on constant voltage (100 V). For a few times it worked at CV but, after a week or so the machine would automatically switch to constant current by itself. And this only ...
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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 ...
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28 views

Which disorders are fully concordant?

I work in neuroscience, mostly Alzheimer's disease (AD), with some work in autism spectrum disorder (ASD). The work is in gene regulation and epigenomics. I'm familiar with monozygotic twin (MZ) ...
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1answer
185 views

Genetics problem-Height of a plant

An inbred strain of plants has a mean height of 24cm. A second strain of the same species also has a mean height of 24cm. When these plants are crossed the F1 are also 24cm in height.However, when the ...
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82 views

Why is the human body hair not uniformly colored?

Most of my body hair is black however my lip hair is light brown/blonde the rest of my beard region is black. Since hair color is genetic what causes this?
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220 views

Possible Genotypes — Linked Genes

Please consider the following question: Genes A and B are located on the same chromosome. If two individuals with the genotype shown below are crossed, which genotype could be formed? Let / ...
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470 views

How was the Huntington's disease gene's location found?

I read in the book "Why we get sick." by Nesse and Williams that: Steady detective work and fabulous luck have enabled geneticists to pinpoint the Huntington's gene on the short arm of ...
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1answer
82 views

How does gene expression work in an adult organism? Is everything encoded everywhere?

The color of a person's eyes are genetically predetermined. If I knew how and in which gene(s) colors are encoded, I could change these genes in the ovary and sperm and thus change the eye color of ...
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2answers
126 views

Advantages of pain sensation?

The hazards of congenital insensitivity to pain (CIP) are well-known. This question is about the obverse: what selective advantage, if any, does the normal sensation of pain confer? I'm thinking of ...
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1answer
80 views

Population Genetics Question

Can someone please help with this question? Here is my working (just in case it is not clear: 1/300*1/30*1/2) but is this actually correct or do I need to multiply by 0.5 once again? I appreciate ...
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What is TILLING?

How does TILLING (Targeting Induced Local Lesions in Genomes) work? What is needed to perform a TILLING experiment, and what kind of information can we get out of it?
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41 views

What are the methods for infering genetic interactions?

Is there a classification of methods for inferring genetic interactions? I mean some work published, utilizes genetical genomics data. Is this possible with expression data alone? And how about ...
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1answer
50 views

How can a YAC be screened against a cDNA library and a cosmid library of genomic DNA to find a gene?

I am reading fw2.2: A Quantitative Trait Locus Key to the Evolution of Tomato Fruit Size (doi: 10.1126/science.289.5476.85). The authors are trying to find the gene that makes tomatoes bigger. As far ...
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2answers
174 views

How does a new species survive without suffering inbreeding?

Just what the title states. The thought came from reading When has an organism evolved enough to be called a new species? I'm probably wrong but I understand new species happen sporadically rather ...
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1answer
326 views

Why does the slope of parent-offspring regression equals the heritability in the narrow sense?

Background ---- Notations and assumptions ---- let $W_{ij}$ be the fitness associated to the genotype $AiAj$. $x$ is the frequency of the allele $A1$ in the population. The frequency of the allele ...
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3answers
420 views

Fisher's Fundamental Theorem of Natural Selection

Ronald Fisher discovered what he, with humility, called the Fundamental Theorem of Natural Selection. This theorem says (in its modern terminology): The rate of increase in the mean fitness of any ...
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1answer
77 views

What does min mean?

I read that "trp operon is located at 27 min on E.coli chromosome." What does "min" mean ?
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59 views

Brainbow fluorescence labeling technique

I have this picture describing the Brainbow system here: The paper I am reading says it uses Cre-lox recombination to express a certain color. If the cell in question was expressing a yellow ...
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1answer
66 views

How can a recessive allele propagate until they manifest?

Suppose a specific gene has two possible alleles. In a given population all members have only the dominant one. By a mutation on member receives the first recessive allele of that population. Is it ...
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1answer
38 views

Knockout Rat Phenotype Database?

Is there a database where I might list the phenotype of a certain rat knockout and/or search for other similar phenotypes? There is a International Mouse Phenotyping Consortium, which has the goal ...
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1answer
94 views

Understanding DNA supercoiling

While trying to understand DNA supercoiling, I came across these lines in the book Genetics by Ursula Goodenough : All natural DNA is superhelical. The axis of the duplex itself follows a ...
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1answer
53 views

Quantitative Traits Genetics

Can someone please help with this question? I'm not so sure whether part A should be 11 inches or something else. Also, is part B correct
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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, ...
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DNA adaptation in human life

Does our DNA adapt by human lifetime? Or do we have the same genetic information from birth to death? I mean: What is usually called "evolution" means "natural selection" like this: ...
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2answers
54 views

What is the role of hippo signalling in oral squamous cells

What role do hippo signalling have on squamous cells in oral health & diseases
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27 views

Could mating/recombination be responsible for evolution of entirely novel features?

The diploid chromosomal architecture is rather interesting. For example, because of diploidy we Humans have to mate. Of course in that sense, because diploid organisms often have mate, this has led to ...
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How many transcription factors are there?

In molecular biology and genetics, a transcription factor is a protein that binds to specific DNA sequences, thereby controlling the flow (or transcription) of genetic information from DNA to ...
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1answer
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What is the standing genetic variation?

I am reading this review. In the first part, the author introduces Standing Genetic Variation, described as: STANDING GENETIC VARIATION Allelic variation that is currently segregating within a ...
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1answer
213 views

Sexual Differentiation in Monoecious plants with unisexual flowers

In monoecious plants having unisexual flowers (eg Zea Mays, Ricinus Communis etc), there must be some mechanism as to produce two sexually distinct flowers from the same genotype. Since both the type ...
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2answers
53 views

Functioning of BRCA2

I know that BRCA2 interacts with RAD51 to repair DNA damage. But how exactly does it function ? What are the other proteins that interact with it ?
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0answers
87 views

Data analysis of transcriptome sequencing data [closed]

I want to learn more about the data analysis and statistics on transcriptome sequencing data. I would like to read some important papers of the field and books and maybe some MOOCS, if they are ...
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140 views

Gibson assembly using NeBuilder

I am supposed to construct a plasmid that contains features from two other plasmids. My strategy is to generate three fragments form the two other plasmids. I was encouraged to try Gibson assembly, ...
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1answer
745 views

Examples of animals with different number of chromosomes that can interbreed?

When I was first started to write this question, I wanted to know how species evolve to have a different chromosomal arrangement, such as having two pairs of chromosomes instead of one? However, I ...
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1answer
36 views

Drosophila Crosses

I have 2 transgenic lines of Drosophila. I would like to cross them and get both transgene in the same fly. To start this cross, does it matter which fly is female or male? Or as long as the female is ...
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Do recessive alleles really exist?

This question may seem illogical to some, but I seriously have this doubt. I searched google for some proofs but they were extremely complex and I couldn't understand anything. I was just wondering ...
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Quantitative Differences : DNA and Gene

After HGP, we are not having many databases which consist of several notepad files of ATCG.... Can we distinguish quantitatively a given A,T,C and G stretch as DNA or Gene?
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1answer
53 views

Gene Complementation Question

Hi everyone! Here is a diagram of a genetics complementation problem. My main concern is regarding number 3d. I'm assuming that in this case, it would be complementary interaction and thus ...
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1answer
50 views

How do mosquitoes maintain telomere length?

While the vast majority of eukaryotic organisms maintain their chromosome ends (telomeres) via telomerase, an enzyme system that generates short, tandem repeats on the ends of chromosomes, other ...
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1answer
69 views

Genotypic distribution of a population with two characteristics and linkage

I am currently doing some research into distributions and probabilities with Mendellian genetics. I came across this problem that I cannot seem to wrap my head around. Given that the population has ...
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1answer
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Distribution of genotypes after adverse selection

I am doing some research into Mendelian genetics and came across this phrase called adverse selection. I found a few questions but I am unsure of the calculations. ...
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380 views

Promoter in the lac operon

Here is the question: Suppose an experimenter becomes proficient with a technique that allows her to move DNA sequences within a prokaryotic genome. If she moves the promoter for the lac operon to ...
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1answer
332 views

All flowering plants gives fruits. Why does jasmine flower plant not yield fruits?

My question is actually my long term doubt. I have seen most of the flowers turning into fruits. But why not this jasmine flower?
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1answer
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What is the significance of and biological mechanisms demonstrated in lac operon?

I would appreciate it someone could explain clearly how the genes in the lac operon of E coli are activated to allow the bacteria to metabolize lactose? The part that I really don't understand is ...
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1answer
113 views

Genetics independent assortment?

As indicated in this question, what do you think is is the best explanation for the observed progeny, is it because distance between genes affects recombination frequency? My main concern is ...
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1answer
192 views

Genetic Drift: Models, assumptions and empirical observations

There two main mathematical models to describe the process of genetic drift are Moran model and Wright-Fisher model. My questions concern the assumptions of these models, the existence of other ...
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1answer
130 views

Gene pool simulation [closed]

this simulation, you sampled the gene pool without replaceing beads in the beakerafter you drew each one. Thus, f(A) and f(a) in the gene pool changed slightly after each bead was drawn. For example, ...
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1answer
87 views

calculate the number of heterozygotes [closed]

The ability to taste PTC is due to a single dominant allele "T". You sampled 215 evolution students, and determined that 150 could detect the bitter taste of PTC and 65 could not. Assuming this trait ...
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1answer
51 views

GULO only for mammals?

I am not a biology student, but just want to know if GULO gene are present only in mammals or all species possess it ? And is GULO gene active in human fetus?
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37 views

What indices can we use to describe fitness landscapes?

We usually talk of smooth or rugged fitness landscape. Are there any (standard) indices to measure the "structure" of fitness landscapes? For example, one might consider the mean epistatic ...