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

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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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Why is an allele dominant or recessive? [duplicate]

Alleles refer to duplicate genes, where one allele can be dominant over the other. What makes an allele dominant or recessive, given that both code for a single protein?.
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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 ...
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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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Genetic effects on personality

It is said that genes are partly responsible for the choices we make in our life; our genes help to create our environment, and then that environment can influence our personality. So, beside genes, ...
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Are there any DNA base sequences that are fully conserved between the genomes of all humans?

That is, they don't differ throughout the entire population. I understand of course that we can't DNA sequence every human, so by "fully" I mean there's an incredibly small probability of there being ...
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Are alleles equally sized?

If alleles occur at the same locus on a chromosome, does that mean they are of the same size? I was under the impression that they were, but I saw a gel electrophoresis testing different alleles of ...
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Do the eggs for larger litters come from the same meiosis events, or different ones?

There are some species of animals that give birth to more than one pup at a time. In these species, are the fertilized eggs all from one or a limited group of meiosis processes, or are they from ...
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What is Mendelian Randomization, and how is it used to infer causality in epidemiology?

Studies of human traits and diseases are inherently confined to observational studies, known as epidemiological studies. This can make it very hard to determine what actually causes a particular ...
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Can molecular genetics make a boolean variable from a continuous variable?

In the same kind of idea than this question. Gene expression are regulated through complex interactions. The concentration of enhancers and repressors is an important aspect that dictate the level of ...
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177 views

(How) can a pink grasshopper exist?

I saw this foto on Reddit recently: Is this possible? How can a grasshopper become like this? Is this just natural genetic mutation?
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What are some (bioinformatic) methods to characterize potentially novel gene transcripts?

I am working with a few novel transcripts of genes- before I confirm their existence experimentally, I would like to perform some bioinformatic analysis. I have already considered coding potential, ...
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291 views

What is the relative power of GWAS studies in different species?

I would like to know of any publication studying the relative power of GWAS studies in different species. For example, I've seen reports that say genotyping and GWAS in dog breeds is much more ...
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phylogenetic analysis of gene enrichment?

Are there any tools to do phylogenetic analysis of gene enrichment? This is, I have a list of genes from an experiment performed in several species, with a z-score that can be described as ...
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935 views

GWAS: why is replication in another cohort so crucial?

Almost all the landmark GWAS (Genome-Wide Association Studies) reviews agree that, for a GWAS finding to be valid, it needs to be replicated in an independent cohort. What exactly is the rationale ...
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78 views

SNPs and locations

I am new to reading raw DNA. When comparing two people's raw data, why does one person have a different SNP than the other, at the same location, on specific chromosome? But on a different chromosome ...
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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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121 views

Effect of sex-ratio on the effective population size

As stated on this wikipedia article, the effective population size $N_e$ when the sex ratio differs from $\frac{1}{2}$ is $$N_e = \frac{4N_mN_f}{N_m+N_f}$$ I understand the biased sex-ratio ...
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218 views

Can plants live forever? [duplicate]

I know that some plants die for old age like a lettuce. But there are trees like Baobabs or larger Ficus in the tropics of whom we don't know their age. And trees like spruce reaching 9950 years old, ...
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117 views

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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Are there any mutagens that can undo the mutations they cause?

I was reading a section from my textbook about tautomeric shifts, and it seems to suggest that there are some mutagens that can be directly responsible for the phenomenon. The section is mainly ...
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158 views

Hill-Roberston effects and effective population size

From this article, first page, middle of the second column: Even if harmful alleles do not become fixed, they can still reduce the efficacy of selection on neighbouring loci through a process ...
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Difference between mutation and DNA damage

What is the strict difference between mutation and DNA damage? As far as I understand it, a mutation is an alteration in the genetic sequence, having "tricked" the repairing machinery and thus ...
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242 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 ...
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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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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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239 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 ...
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Please explain this disrepancy about ageing

We read that ageing is related to cell death when we run out of telomeres at the end of our DNA molecules. Humans live roughly for 70 years - the traditional three-score years and ten. This compares ...
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Are gene variants at different loci also called alleles?

I think the title says it. I always read that alleles are gene variants at a given locus, which confuses me. Thanks!
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How well supported is the hypothesis that aging is mainly caused by the number of mutations in tissues?

I heard the hypothesis, that the (main) reason of aging is the increasing number of mutations in body tissues. The higher the number of mutations is, the older tissue is. Is this true? And how well ...
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What's a non-allelic gene?

Non-allelic or non-alletic I stumbled across the term in my Human Genetics textbook. It didn't explain it there, and a quick google search only showed scientific papers that refer to 'recombinations ...
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147 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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Are there mechanisms that limit the amounts of time conjugation and F-plasmid transfer can happen? If yes, what are they?

Not all bacteria have acquired F-plasmids through conjugation. Some of the mechanisms for this are unsuccesful conjugation events (mechanical disruption), no transfer due to integration in bacterial ...
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“Enhancers” of enhancers?

I am looking for examples (if any) of genomic regions which regulates the activity of enhancers, either augmenting or reducing it. Essentially some kind of enhancers (or repressors) of enhancers to ...
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What percentage of the (additive or not) genetic variance is explained by the 'n'- most important loci?

Standard models in population genetics look up at the evolution of few loci which impact fitness. The variance in fitness is determined by the genetic variance and the environmental variance (and the ...
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Can a woman possessing 1 mutated allele show attenuated color-vision deficiency?

Women possess two X chromosomes. However, during development, when the embryo has about 32 - 64 cells, one of these chromosomes is randomly inactivated (in each cell) by an lncRNA named Xist. As a ...
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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 ...
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Evolutionarily speaking, why do humans have 46 chromosomes

In humans, each cell normally contains 23 pairs of chromosomes, for a total of 46. Monkeys, chimpanzees, and Apes have 24 pairs (twenty-four pairs), for a total of 48. What caused humans to have 46? ...
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How does Artificial Selection work?

As far as I know for evolution to work mutations are necessary. Mutations are the raw material on which natural selection works. But mutations are always completely random and human beings have no ...
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Is it possible for a child to grow taller than their tallest parent?

I have heard that offspring can't grow taller than either of their parents but I've also heard that sometimes some gene activation can skip generations. Is it possible for a child to grow taller than ...
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A free book/resource for learning genetics?

I took an undergrad class in genetics. I felt it was not too intensive and I do not feel prepared for grad school (if I can manage to get in.) Does anyone know of a preferably free resource for ...
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Why don't flies avoid the motorway?

Flies have a short lifespan, therefore evolution should technically happen over a shorter period of time (years). Flies die all the time from getting hit by cars on the motorway. Those flies that ...
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How to identify genes required for biofilm formation

This is just a homework question: Q: Let’s assume that there is an unknown set of E. coli genes that are required for biofilm formation. Describe a genetic experiment you could perform to try to ...
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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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Functions of the CFTR gene?

I am a senior in high school and I am studying cystic fibrosis. I don't quite get the function of the CFTR gene as this is my first time dealing with this type of heavy scientific info. I had ...
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What do the signs +/+ +/- mean in this image?

I don't understand what this graph is supposed to explain, especially what the signs +/+ or -/- mean. I just know it characterises some rats.
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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 ...
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What are the different ways an exon gets spliced?

Exons are produced by more than one mechanism, e.g. splicing out introns after transcription, if I remember correctly. Please list all mechanisms.
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Where do amino acids get attached to tRNA and where is it synthesized?

Some very basic parts of transcription/translation seem to be left out in various literature. I can't find the answer to this anywhere: How exactly is tRNA synthesized? I realize that mRNA is ...
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What is an operon?

What is an operon in a eukaryotic cell, and how does it regulate the expression of genes? I've already read Wikipedia, but it is not enough clear to me. Unfortunately my knowledge in genetics are very ...