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6

They aren't, anymore. It was a fair guess at the time, but first I think we should define what cloning in this context mean. Our own cloning tag says: The process in nature or in the lab by which a new organism is created that is genetically identical to its predecessor. For animals - I'm going to use Dolly as an example since you do as well - when ...


4

Preamble Any answer regarding the origins of our biochemical evolutionary origin will be reasonably speculative given that this is a very hard question to scientifically test and this field is generally understudied to say it is pretty much the most fundamental biochemical question. But there are a few reasons why RNA makes sense as the prime genetic ...


4

Those are the break points of the inversion. So chromosome 4 was cut at p13 and q22 and the fragment was reinserted in the reverse direction, giving a pericentric inversion.


3

You have made an incorrect assumption-- that all the genes on both chromosomes necessarily remain intact. It's possible that they do, and the the translocation is harmless. But the transition point could be within a gene. This would usually lead to that copy of the gene becoming inactive, which can cause diseases just like any other loss-of-function ...


3

In the Down syndrom typically, the translocation does not induce (usually; see later) any disease. We call someone carrying the translocation a "balanced carrier". The problem arises after, at the moment of segregation. When balanced carriers reproduce Consider someone who has a translocation as you showed. You showed only one chromosome of each types ...


3

No they are not. High gene density is correlated with GC content. Most genes are found in GC rich isochores, which are not distributed uniformly (as can be seen on any karyotype). It is also shown through direct sequence analysis (gene density shown in red, GC content in green): Venter et al. go on to say: This inhomogeneity, the net result of ...


3

In a population of mice, the presence of black spots is the result of a homozygous recessive condition. If the frequency of the allele for this condition is 0.15, what is the approximate percentage of heterozygous genotypes in this mouse population? (Assume that the population is in Hardy-Weinberg equilibrium.) We know the frequency of the allele (0.15) ...


3

C765 is a transgenic Drosophila strain that has a specific Gal4 expression pattern ("embryonic salivary glands and larval wing and leg discs"). Gal4 is a transcription factor from yeast which binds an upstream activating sequence (UAS) and also happens to function in other species (like flies). In the Gal4/UAS system, a strain expressing Gal4, under the ...


3

The first DNA circle is double-stranded. If you could melt the double-helix completely you would not be able to pull the two stands apart without breaking the sugar-phosphate backbone of at least one of the two strands. This is a topological problem, the two strands are linked to each other. Now consider DNA replication. In the simplest example there is a ...


3

Remi.b talked at great length in his answer about copy-number variation and the generation of new genes. However, I don't think he quite answered what I think is a pretty basic question: How many copies of any particular gene are there in (a human) genome? The answer to that question is also simple: two - one on the chromosome from the mother, and one ...


3

Cell cycle Talking about physical copies of gene, we would indeed have at least 1 copy during the haploid phase, 2 copies during the diploid phase and 4 copies during the mitosis (and during the first phase of the meiosis). Of course, species having mitosis during the haploid phase would have 2 copies of the gene during the mitosis. I am not talking about ...


3

The short answer is yes, other animals can experience dwarfism, including dogs, although it may not be what you are expecting. Dogs are apparently particularly susceptible but they often are a special case. We've so heavily bred dogs for whatever traits we desire, so now entire breeds are affected by dwarfism, such as dachshunds and corgis. The reality is ...


2

From the way I have read what you have written z(1-z) translated into a sentence would be the frequency of the neutral variant (z) times the frequency of all other possible variants (1 - z) at the particular time t. Nucleotide diversity is then the average of 2 times the sum of all of the frequencies of neutral variants (z) times the the frequency of all ...


2

The term allelic class is defined in Innan and Tajima (1997) Suppose that there are two nucleotides, say A and T, in a particular site.Then, we can divideDNA sequences into two classes: one class includes sequences with A and the other includes sequences with T in this site. We call such a class an allelic class Two elements that were misleading (for ...


1

In short; Theoretically yes. In practicallity no. Non-specific PCR require random primers to anneal to a target sequence to initiate replication during PCR. Theoretically this should anneal to every combination of bases and therefore allow the amplification of all DNA (or at least in a fragmented form). Practically, all the primer combinations will have ...


1

Well, though it is possible to have SNPs of more than two alleles, and some exist, due to the low probability of having a basepair change twice in the same base-pair (there are aproximately 3.000 Mb in the human genome) and have it in more than 1% of the population (remember we are talking about single nucleotide polymorphism) to classify as a polymorphism ...


1

Probably they are not all the same species, as there are many fruit fly species in the UK and all over the world. It is also probable that you are not creating hybrids, as fruit flies have quite specific mating behaviours that change rapidly sometimes even between strains. Anyway, you are assuming that the eggs come with the fruit, but that's hardly ...


1

I think that the rest of the paragraph that you left out of your quotation helps to clarify. The CHO have 21 chromosomes, while the somatic lung cells have 23. Neither case is exact for Chinese Hamsters, 2n = 22. So they have almost the complement of chromosomes that a diploid Chinese hamster somatic cell would have but they are missing one or have one ...


1

Yes, people can definitely grow taller than their parents. Height is a polygenic quantitative trait (so affected by many genes), that is also strongly affected by environmental factors. You are also forgetting that there is a sex difference in height (~14 cm, Wright & Cheetham, 1999), so the height of the mother does for instance not set an absolute cap ...



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