Questions tagged [genetics]

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

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Why does size decrease across the sequence of human chromosomes?

The following graph shows a decrease in the number of base pairs per chromosome across the sequential set of human chromosomes: Is this because chromosomes were originally numbered by their size on ...
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1answer
265 views

How can the number of genes increase through evolution?

I am aware of the basics of evolutionary theory, however I don't understand how mutations can add genes over time. Am I correct in thinking that creatures within the same species who mutate to have ...
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What is the instructional language of DNA?

DNA carries most of the genetic instructions used in the development, functioning and reproduction of all known living organisms and many viruses (Wikipedia). Is it already know how ATCG's sequences ...
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3answers
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Can genes change as we age?

Let's say you're a 23-year-old man who impregnates a woman. Will your genes be the same if you were to impregnate another woman at age 35? Will your genes in those 12 years have changed/mutated/become ...
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Why do most animals never seem to evolve over millenia?

People often say, including those with extensive knowledge in biology, that a certain species of animal will evolve in one way or another: From changing environments. Mutations. Possibly even genetic ...
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2answers
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Does one parent transmit more DNA to the offspring than the other one?

Does one parent transmit more DNA to the offspring than the other one? Or do both parents always transmit the same amount of genetic material to their offspring? In other words, can a baby be ...
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4answers
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Why is a heritability coefficient not an index of how “genetic” something is?

On his blog, Eric Turkheimer writes: [T]aken as a number, a unit of analysis, heritability coefficients are funny things to aggregate on such a massive level. What exactly are we supposed to ...
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How does DNA still work after recombination?

If you take two computer programs and randomly swapped pieces from each of them. The result is not going to work. It will just be garbage. If you take two novels and randomly swapped chapters the ...
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4answers
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Why do men have nipples?

I'd be tempted to call nipples in men vestigial, but that suggests they have no modern function. They do have a function, of course, but only in women. So why do men (and all male mammals) have them?
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How much of my ancestry will match with my brother?

Recently, my brother (full sibling) got his ancestry checked from MyHeritageDNA. They have a similar service like 23 and me and I've found out that both companies are offering the basic service almost ...
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4answers
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Could we detect GMO foods if there were no samples to compare with?

In my understanding, there’s nothing “special” in how a GMO product is composed inside compared to a “natural” product. I mean, still, same principles apply to both: some DNA that controls protein ...
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Do men and women have the same number of genes?

As far as I know, humans have 23 pairs of chromosomes, each one which contains a particular amount of genes. But in the "last" pair, men have a XY pair chromosome, and women have a XX pair chromosome. ...
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Are mutations a source of genetic variation?

Here is a question from the book SAT II Success Biology E/M (where the SAT is the exam taken by the American high school students): Which of the following statements is true about mutations? (A) ...
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893 views

How can a chromosome translocation in somatic cells lead to disease?

Looking at this picture... (source: nih.gov) ...I get the impression that the part of chromosome is attached to other chromosome, but it is not mutated. When we assume that all genes in the ...
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1answer
598 views

Microsatellites and Minisatellites: Which of these form the basis of DNA fingerprinting?

I'm in a fix. Prepare yourself for a long read We've just learned about minisatellites and microsatellites at class (okay, by "learned", I mean we were told their definitions and essentially ...
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1answer
23 views

Repopullation after a mass extinction [duplicate]

Is it possible to restart the whole human species with less than 10 individual. let say that the whole human species was wipe out of the surface of the earth by a catastrophe only 8 different couple ...
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1answer
29 views

What is the difference between Regulatory Gene and Modifier Gene?

If both controls the expression of another gene by physically or genetically interacting with the target gene, which attributes make "Regulatory gene" different from "Modifier gene" or vice-versa?
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GEN file format, SNPs and alleles

I have a few questions I can't seem to get a straight answer to, regarding the .gen file format and also biology in general. The ...
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0answers
48 views

The Viceroy Evolution Paradox [duplicate]

The viceroy butterfly generates a toxin compound which make it distasteful to predators. Biologists agree that the viceroy must have developed this trait as a passive defence mechanism to prevent ...
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0answers
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what is the difference between homozygous and heterozygous duplication?

In a genetic test result it's written homozygous duplication or heterozygous duplication Does it mean four copies of the ...
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0answers
29 views

The afflictions of Tarrare

Are there any conjectured mechanisms that cause Tarrare's extremely oversized stomach and abdominal cavity? Along with his superhuman appetite of course. Whether from a medical perspective or a ...
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1answer
40 views

Interpretation of genetic results

Result of genetic testing indicated: c.341del, p.Thr114Lysfs*37. The c.341del probably means:deletion at the cDNA 341 nucleotide. Buy what does the second part:p.Thr114Lysfs*37 ?
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2answers
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Solving Hardy Weinberg problems

I really fail to understand Hardy-Weinberg equilibrium and can't find an easy enough source of information. Can you help me to understand Hardy-Weinberg equilibrium? My goal is to be able to solve ...
7
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1answer
119 views

Evolution of Wheat

In the evolution of wheat, there are two instances of chromosomal doubling, when Emmer wheat Triticum turgidum was formed from Einkorn wheat, and when Triticum aestivum was formed from Emmer wheat. ...
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0answers
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Does the law of independent assortment apply to homologous chromosomes or alleles, or both?

My textbook is giving me two definitions 1st def: "random orientation of homologous chromosomes at the metaphase plate in meiosis 1." 2nd def: "alleles for one gene separate into gametes ...
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2answers
138 views

Why is Turner syndrome a problem?

Turner syndrome is a chromosomal disorder where one of the X chromosomes is missing. For more details visit the Wikipedia page I don't understand why missing one X chromosome would be harmful. In ...
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1answer
318 views

Which is the reference 16S rRNA?

Recently, I've stumbled upon a fact, which hasn't bothered me for many years. The fact is that all universal 16S primers are written as "[FR][0-9]+" (in regex notation), that is they have a position ...
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2answers
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Why do people with type O blood have anti-A and anti-B antibodies?

People with type O blood have anti-A and anti-B antibodies, even without receiving a transfusion. Why?
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315 views

Minor Allele Frequency (MAF) higher than 0.5? [closed]

I have a set of data in PLINK format (*.bed, *.bim and *.fam files). There are around 2000 individuals in my dataset. I used PLINK to calculate allele frequencies in the population: ...
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1answer
81 views

Is evolution theory falsifiable by whether mutations result in a loss or gain of genetic information? [closed]

If I understand the theory correctly, evolution revolves around the process of adaptation of a being to its environment which results in the increment of survival and reproduction chances for that ...
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1answer
109 views

What is mRNA expression level?

I cannot find a clear explanation of what is mRNA expression level, and how to measure it. I would appreciate if someone explained it or gave a reference.
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1answer
56 views

How do biologists discover information from fossils? [closed]

I have a query about the study of fossils (palaeontology). Let me know about the study of fossils. How do biologist discover "DNA" information from dead and old fossils such as a dinosaur? (answer ...
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1answer
83 views

Can I train my non-dominant hand and make it dominant?

Are our dominant limbs decided on birth or is there some way in which I can train my non-dominant hand and make it as coordinated as my dominant?
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0answers
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What are the issues with excessive tandem repeats in replication?

Why is it that tandem repeats like CAGCAGCAG cause primer-template misalignment and diseases like Huntingtons disease? By my understanding, too many such repeats can cause strands to form hairpins and ...
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1answer
191 views

Do all gene mutations in pathogens lead to more harmful consequences for humans?

It seems that the concern we always hear is that bacteria and viruses mutate to dodge our treatments either through random mutations or survival of the fittest. Do harmful living things ever mutate to ...
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1answer
24 views

What does Ercc1-/- / DAT-Cre+ mean?

I really need to know what Ercc1-/- / DAT-Cre+ mean. I think the 1st part means that the mice don't have the Ercc1 gene (knockout). But what about DAT-Cre+? This question arised from reading the ...
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1answer
35 views

How are mitochondrial diseases like MERRF inherited?

I am doing a project on the disorder MERRF in Mitochondrial DNA. I have to make a pedigree and explain how it is transferred on from generation to generation. I know that it is inherited maternally, ...
2
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1answer
92 views

What makes an E.coli an E.coli, genotype or phenotype?

According to this paper, among 61 strains of E. coli they studied only 6% of the genes are common in all. Which means that the overwhelming majority of the genes are not shared. And wikipedia ...
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1answer
132 views

Are all genetic disorders inherited?

I know that genetic diseases such as cystic fibrosis are often passed down through generations and are therefore classified as genetic disorders, but if a mutation occurs spontaneously, which for ...
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1answer
56 views

Why not self pollination for finding the genotype instead of test cross?

Test cross can tell us what's the genotype of a plant is. But we can know that even by self pollinating the plant. For example, If a garden pea plant has the genotype TT, then self pollinating them ...
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2answers
94 views

How much of my ancestry comes from each grandparent?

Three of my grandparents were Eastern European, back at least several generations. I recently discovered that I am less than 25% Eastern European, the rest being Western European and other. How likely ...
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0answers
41 views

What are the different types of SNPs?

When I search for this online I get answers such as substitutions, deletions, insertions etc. But I mean in the sense that I have been reading different terms infront of the word SNP such as: lead SNP,...
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2answers
553 views

Chromosomal pair possible in metaphase - I

There is this question which was asked in my exam. A diploid cell contain 6 chromosomes. How many possible random arrangement of homologous chromosomes could occur during metaphase-I? (consider ...
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1answer
50 views

How can inbreeding be used for selecting mutations?

I understand that inbreeding, after a number of generations of crossing genetically related individuals eventually yields homozygotes, however I can't seem to understand how it can be used for ...
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1answer
38 views

Have there been new discoveries concerning the perception of taste for the last 10 years? [closed]

What are the last discoveries concerning the perception of taste for the last 10 years? We discovered the 5th flavour: umami. Also the 6th and 7th: oleogustus and starchy. Anything else? Maybe in ...
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1answer
118 views

What's the exact meaning of and how to derive the coefficient of the path from sire to offspring?

According to Wright's Coefficients of Inbreeding and Relationship, the coefficient of the path from sire to offspring is given as $p_{o \cdot s}=\frac{1}{2}\frac{\sqrt{1+F_s}}{\sqrt{1+F_o}}$ But ...
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1answer
70 views

Can environmental pressures affect genes in one generation? [duplicate]

Environmental pressures are the catalyst of evolution. Pushing a species to adapt to changes therein. My question is can these mechanisms cause significant adaptation over one generation(parent-> ...
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1answer
48 views

What impedes the understanding of genotype/phenotype relationship without statistics? [closed]

Most genetic research tries to establish a relationship between a certain genotype and certain phenotype. To me this is like trying to understand a system as a black box, where you try to establish ...
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0answers
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What genes in a plant determine whether a stem is erect or climbing?

I was randomly reading this Wiki article on Jasmine and this question crossed my mind after reading the following lines: Jasmine can be either deciduous (leaves falling in autumn) or evergreen (...
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1answer
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What exactly does the phrase “chimerical sharing” mean in this abstract?

The Gizmodo article Australian Siblings Are Semi-Identical Twins, Some of the Rarest Humans Ever links to the new paper in NEJM Molecular Support for Heterogonesis Resulting in Sesquizygotic Twinning ...