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17

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 ...


16

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 ...


14

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 ...


10

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 ...


8

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 ...


6

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 $n$ ...


5

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 ...


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 ...


4

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 ...


4

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 ...


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 ...


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 ...


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 ...


3

The reason that there are no stripes when black and white people get babies is the fact that the number of pigment cells is the same for black and white people. What is different is the amount of pigment produced, and it will be different in the kids as well (lighter than the dark parent, darker than the light parent) See references 1 and 2 for details on ...


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 ...


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

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). ...


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, ...


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

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 ...


2

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

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.


1

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


1

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 ...


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 ...


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 ...


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 ...


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.


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. ...



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