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0

http://phagesdb.org/phages/Bxb1/ here you can click "Locally BLAST this genome" it will give you the sequence in FASTA format and then you can click BLAST if you want additional information about the sequence, alignment, etc


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After thinking about it for a while I have arrived to a slightly but important different view on this problem. I will try to explain the statistics behind it to the best of my knowledge. I will use the eyes’ color probabilities in @Remi.b’s response, but of course those may not be accurate and the results can change accordingly. The problem is to determine ...


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Possible...yes of course! The answer could stop there but I guess you want to ask how likely it is. Here is a chart of probability of a given kid to have eyes of a certain color given the parents eyes color. (Note that the second column contain probabilites and not odds contrary to what the figure is stating). The probability that $k$ kids out of $n$ ...


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Practically, there is an obvious barrier to changes in chromosome number: haploid cells produced by diploids must contain exactly one copy of each chromosome (or chromosome section, or locus). Otherwise over- or under- expression of genes can lead to dosage problems. Across all of diploids some large groups show strong conservation of number of chromosomes ...


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Yes there are many such mechanisms. One of the simplest, but perhaps most easily overlooked, is metabolism. Conjugation requires ATP. In environments with low levels of nutrients, heterotrophs might not have enough "extra" ATP to fuel the conjugation process. Note that both donor and recipient need to expend ATP in conjugation. The donor needs to make ...


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It has to do with dosage compensation: The Y chromosome contains relatively few genes. Interestingly, chromosome 21 and 18, which are over represented in the most common viable trisomies, are also relatively small. Humans already possess a mechanism to compensate for additional X chromosomes: X inactivation. Normally this inactivates the extra X ...


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The morbidity is high because autosomal trisomies affect somatic / autosomal chromosomes, which are essential to the process of life. In fact, the majority of fetuses affected by autosomal trysomy are miscarried, with a few exceptions (Down syndrome is one). The sex cells have only half the number of chromosomes,23, of which the affected ones are usually the ...


0

I am not used to this expression but basically this expression is a mean $$\frac{1}{m}\sum_{i=1}^m ...$$ ($m$ is the number of SNPs) of the ratio $$\frac{numerator}{denominator}$$ where the numerator is a covariance $$(a_i-C)(b_i-C)$$ and the denominator is the expected heterozygosity $$2pq$$ Therefore, it represents how much do two individuals ...


2

Species definitions are a somewhat contentious part of biology. There are no hard boundaries in nature that mean "this group here is one species, this group here is another species". Some people don't even believe that species truly exist and there are only gradations of relatedness. That being said, the Biological Species Concept is one of the more popular ...


1

MIT Open Course Ware has a course on genetics, which uses the following text: "An Introduction to Genetic Analysis", Griffiths, Anthony J. F., Jeffrey H. Miller, David T. Suzuki, Richard C. Lewontin, and William M. Gelbart, 7th ed. New York: W. H. Freeman, 2000.


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There has been some research in order to explore this direction, for instance, see this reference: A. Weiss et al. - "The Heritability of Personality Factors in Chimpanzees", Behavior Genetics, Vol. 30, No. 3, 2000., in which the authors study five human-like factors - Surgency, Dependability, Emotional Stability, Agreeableness, and Openness. Quoting ...


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GENETICS: Analysis and Principles, 4th edition, Robert J. Booker This book is used in my school's ( NYU Poly) undergraduate genetics class.


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Short answer Skewed X-inactivation may lead to phenotypic manifestation of X-linked color blindness. Background What an interesting question! In a study by Jorgensen et al. (1992) two female identical twins that were heterozygotes for X-linked deuteranomaly were investigated. Phenotypically, deuteranomaly refers to anomalous trichromacy, i.e., reduced ...


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This is a matter of pragmatism in the culture process. Taking 100 colonies instead of 1 increases the inoculation volume by a factor of 100, which then saves you perhaps 2 hours of bacterial growth time before your culture reaches the OD you want. However, mutations and loss of plasmid in culture, while unlikely, are possible, especially if the bacteria ...


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Speaking of your DNA in general, you have alleles from all four of your grandparents. The 22 pairs of autosomes (non-sex chromosomes) can receive DNA from all four with random mixing. On a few chromosome pairs you may be missing alleles from one of your grandparents due to the randomness, but on average you will have about a quarter of your autosomes from ...


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While all colonies on a selective media SHOULD contain a resistance gene, that's a long way from them containing the plasmid you want. A typical cloning experiment will insert a gene of interest into a empty vector backbone to make an intact plasmid. The backbone usually contains some antibiotic resistance gene. If your gene of interest is not correctly ...


1

Remember: A and B are genetic markers that might be linked to the disease gene. Neither A nor B are actually the hemophilia disease mutation (or gene), A or B are proxies, or substitutes for the mutation in the disease gene. Since it is an X-linked recessive, it is only the Mother's two X chromosomes that are candidates. You can completely ignore the ...


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Forever no. For thousands of years yes. And not only plants, other organisms have what is called biological immortality. Look here for some examples https://en.m.wikipedia.org/wiki/List_of_long-living_organisms


0

Probably, there are narrow and wide definitions for imprinting. I am guessing the history of researches about imprinting would be like the followings. Initially, maternal or paternal phenotype transmissions were recognized and some of such phenotype seemed because the maternal or paternal responsible gene does not work. As you know this is clearly ...


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The answers to these questions often boil down to "what do you mean by live forever?". You've included vegetative cloning, so I infer that counts as one living organism for your purposes. In that case, the answer is absolutely. Pando is at least 10 thousand years old and only getting larger. The Cavendish banana is about 150 years old, but produces at ...


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The Coursera Introduction to Genetics and Evolution is an excellent MOOC. If I remember correctly it contains links chapters in the online version of Griffiths et al (i.e. deep links to this: http://www.ncbi.nlm.nih.gov/books/NBK21766/ ) There is also Introduction to Biology - The Secret of Life from EdX, it is not just genetics, it covers a lot of ...


2

At the moment, the youngest diagnosed Huntington's case was 2 years of age. This paper appears to discuss not only this boy's onset, but also the diagnosis of symptoms in the early-onset disease. Here they research a link between age-of-onset and the length at which the repeats are. The thing is that these repeats won't just constantly get longer. There ...


2

Christian, great idea to ask this question here before taking important decisions. Are those media articles a hype? Yes. Over the last 10 years I constantly see those hype stories in media about "revolutionary" large-scale-study/big data projects with mind-blowing numbers (gigabases, teraflops, terabytes, thousands of papers and hundreds of genes). ...


3

I work at the Wellcome Trust Sanger Institute, one of the world's largest genomics centres. We do maintain a website for the public wanting to learn about genomics, but it might be a bit basic for you: YourGenome.org You can get into this field without going through grad school: learn at least one programming language (Python is probably the key one ...


1

From the comment section: We don't have to see the actual changes. It's like chemists who will mix compounds together and obtain a new molecule. They dont see the chemical reaction per se but can test the new molecule to make sure what they predicted would happen had happened. Finally we often use fluorescent proteins to track some of the modification ...


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As you said, the question is pretty broad. Genetics is a big gigantic field and it is quite hard to know what you are exactly looking for. If you could refine into one of the subfields (molecular genetics, population genetics, phylogenetics, etc..) it would be much easier to give you better advice. As you talk about both biology and bioinformatics, it might ...


1

Since there are 2 alleles of each gene and 3 different genes, 2EE3 = 8? Let's test this by making a table, for 1 gene there are two different kinds of gametes, so 2EE1 = 2, for 2 genes there are 4 different kinds of gametes (AB, Ab, aB, ab) so 2EE2 = 4, and you already did the calculation yourself for 3 genes, and 2EE3 = 8. Why don't you try working it ...


0

Your illustration is wrong. During second meiosis the sister chromosomes go to each their cell, not the same cell. This would correspond to switching the colors up in your illustration like this:


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The paper by Lobo and Levin is an attempt to learn a model that represents the inner workings of a biological system by fitting parameters to data. This is a common topic in "systems biology", a model-based approach to studying biology that is popular in some fields. Even for small systems, this is a phenomenally hard problem. Unlike most machine learning ...


0

A genetic marker is, by empirical definition, something that you can unequivocally place on a genetic map. A genetic marker may be an allele of a known gene that confers either a dominant, or a recessive phenotype. Alternatively, a genetic marker could be either a restriction fragment length polymorphism--whose segregation can be detected by either a ...


1

Chromosomal aberrations have defined notations you can find here. The notation rule for multiple genetic abnormalities is to concatenate them. In the presence of an unbalanced translocation two abnormalities will be indicated as you have both a translocation and another event (e.g. deletion, duplication, ...). In your example, as no other ...


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The fruit, sadly, does not hang so low. Short version Lobo et al (the work you refer to) is a nice and not especially novel application of basic Systems Biology modeling approaches to the wound healing system in flat worms. The main barrier to the wider application of such work is the lack of the necessary experimental data. Lobo et al themselves don't ...


1

Genetic markers don't cut the DNA. They're simply regions of DNA sequence that happen to be variable between individuals (see my answer to your previous question). They might be measured using restriction enzymes (i.e. RFLP) to identify the exact difference, but it's not the marker that's cutting DNA. Furthermore, they don't necessarily cause disease. ...


1

This translocation is balanced: if it was not there was a specific sign for specific unbalanced event, for example "del" for deletion or "+" and "-" signs etc.


0

Well the simplest way is to cut the gene at the both ends from operon by means of proper restriction enzymes but in case that you get more than one recognition site then you can use microRNA or proper oligo to make a hairpin loop and break that part If you only want to silence the operon then you just need to cut it nearly at middle of the gene and ligate ...


2

Let's consider all the options. X-linked recessive: I:2 is a carrier and II:5 is also a carrier, and I:1 is affected. Everyone who marries into this family(except for II:2, lucky guy. He better not have any sons though.) is a carrier for the same genetic disorder. While it does work, it's vastly less likely than the other options. Observe: II:4 is affected, ...


4

It's actually very simple. You misunderstood the term polymorph in this situation. A microsatellite is a sequence composed of a short repeated DNA motif. A polymorph satellite is then simply a microsatellite varying in length between individuals, i.e. composed of more or less repeats of the motif. The flanks of the microsatellite are the DNA sequences ...


3

I think you pretty much nailed the problem. If I understand correctly, you are just confused about the approximation that your textbook does, an approximation that is correct but not needed. Let me restate the solution to the problem first. Resolution of the problem As you said the frequency of sick people $\frac{1}{300} = 2pq + q^2$ in this case, where $q ...


0

It is possible to insert a new gene in another organism. The technique is very new. I know I have done it at school where we had a colony of bacteria, and we did some things to them that some of those bacteria would 'adopt' a gene that would make them able to live on a different pertium dish. If you are intrested in these subjects you should try to ...


3

I will focus my answer on the evolution of orb web spiders (Fig. 1), because arachnids, like insects, are relatively non-complex creatures with an obvious systematic behavior (the weaving of highly symmetric, repeating structures). Hence I reasoned this would be a good approach of investigating the answer to this question. The orb-weavers (Orbiculariae, an ...


2

As hello_there_andy (and also the Wikipedia page) has indicated, genetic markers are DNA sequences that can be used to distinguish individuals (can also be tissues, cells, etc.). Linkage of a phenotype with genetic markers is used to identify regions of the genome that are likely causative for that phenotype, as hello_there_andy says, but there is nothing ...


1

This is more of a comment Mutation in tumour suppressor is a recessive trait and there is no active "silencing" of the mutation. If a tumour suppressor is a TF then a mutation in the DNA binding domain can have no effect if there is a complementary mutation in its binding site. This is just a theoretical possibility and I have not heard of any examples as ...


-1

Genetic markers are sequences of DNA that tend to co-occur with some biological property, in a population. Examples E.g. Imagine you have 200 individuals in a population. 100 individuals have some sequence GGGCCCGGGCCC at some locus (position on the genome), and those 100 individuals have blue eyes. The remaining 100 individuals have AAATTTAAATTT, at the ...


0

It is not possible to know in most cases whether a chromosome is maternal or paternal without knowing the genome sequence of both mother and father (with some additional effort; see below). There are certain exceptions and these include chromosomes that bear imprinted genes. For example H19 gene on chromosome-1 is maternally imprinted i.e. the paternal ...


0

The cytogenetic notation seems to refer to parts of the chromosome when they're being karyotyped when the chromsomes are condensed in metaphase. If so, I think you might be able to use FISH to look for pieces of maternal or paternal genetic content on the chromosome. It looks like you can use mat and pat to refer to a maternal or paternal chromosome.


2

Unless someone has actually done this specific fusion and reported on the activity, this question won't have an answer. I can't find anything about proline aminopeptidase fusions, but enzyme-HlyA fusions have been done that retained activity similar to the wild-type protein (examples: cutinase, β-lactamase). Your fusion might work fine or folding might be ...


2

As you probably know, there exists many different species concepts (or definitions of species). Often, you see a separation into at least six different categories of species concepts, which are then often subcategorized futher (and they can also overlap to some extent), namely: Biological species concept Phylogenetic/cladistic species concept Evolutionary ...


0

In Hardy-Weinberg problems the frequency of a homozygous recessive genetic occurrence in a population is q2. Sort of but not quite. If the locus has two possible alleles, $A$ and $a$, the frequency of each allele in the population is $p$ and $q$ respectively. If the population size ($N$) is 500 diploid individuals, there are 1000 loci ($2*N$, because ...



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