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14

The ABO blood type is controlled by a single gene (the ABO gene) with three types of alleles inferred from classical genetics: i, IA, and IB. The IA allele gives type A, IB gives type B, and i gives type O. As both IA and IB are dominant over i, only ii people have type O blood. [1] So from this standpoint, normal Mendelian genetics cannot explain the blood-...


13

Purely going off experience here having used golden gate assembly methods for 5+ years now, there is a definite lack of literature regarding small part assemblies. In my current lab, we use CIDAR MoClo (a golden gate method) and have assembled 100's of constructs successfully with parts as small as ~ 70 bp. However, when we assemble smaller parts we tend to ...


11

If you're synthesizing the insert then you just design it with restriction sites that are compatible to the vector. Otherwise, you can design PCR primers that have restriction sites in them. That way when you amplify your insert you'll attach the restriction sites to it. EMBL, Addgene, and NEB all offer somewhat more detailed explanations of this on their ...


10

Consider that: RNA polymerase (RNAP) is a large complex (~400 kDa in bacteria); inertia and drag would hinder its rotation. RNAP is attached to its RNA transcript, which becomes increasingly large as transcription proceeds thus increasing inertia and drag. Additionally, if RNAP were to begin to rotate around DNA, the transcript could begin to wrap around ...


9

A plasmid is a length of circular or linear double stranded DNA that exists independent of chromosomal DNA with a cell (i.e. extra-chromosomal DNA) and often confers a selective advantage to an organism such as antibiotic resistance. Plasmids have been identified in archaea, prokaryotes, and eukaryotes and allow horizontal gene transfer within a population, ...


8

It depends on the regions of sequence homology between the two chromosomes. Crossing over occurs through pairing of homologous regions. If there's a substantial stretch of chromosome without a matching homologous region on its pair, that non-homologous region should loop out and not be involved in crossing over. Crossovers will occur only in paired ...


8

I don't have hard data to share regarding you question, but I can provide some anecdotal evidence. I have used golden gate assembly to build hundreds of plasmids using ~20bp annealed oligos, as well as hundreds of plasmids using ~70bp promoter+RBS, 720 bp eGFP, and ~70 bp terminators encoded on plasmids into a ~6kb backbone. In these cases I use 40 fmol ...


5

The De Vlaminck Lab has extensively studied the origins of circulating cell-free DNA (cfDNA) in human plasma and its utility in detecting infections and organ injury.1,2 Concerning your question of parasite DNA detection and parsing signal from noise, I don't think you'll find a better resource than their 2020 publication in Microbiome.3 If the (uncited) ...


5

I assume you are referring to the "typical 5’—3’ order of appearance". The correct way to pronounce these is with the word "prime", that is, "Five prime to three prime". These are not units but refer to the directionality of RNA/DNA and the numbers five and three refer to specific carbon atoms arranged in the sugar molecules ...


5

because fractals are emergent structures created by simple rules, as are many biological structures. The same kind of simple recursive signals that lead to fractals are simple enough to be stumbled on by biological evolution and are effective ways to deal with the scaling problems created by the square cube law. https://www.complexityexplorer.org/system/...


5

It may also be worth considering how you are amplifying and isolating your small part. Gel extraction kits sometimes have an optimum DNA size ranges that may prevent recovery. Or if your part is similar to your primer length you may see considerable contamination in your 'purified' product if say the size of a single RBS.


5

There are a few plausible ways: As someone mentioned in the comments; Alcohol works well for this. We have samples from a hundred years ago (e.g. Thylacine), which have been stored at room temperature in a museum for that period of time and have had DNA easily extracted from them. Unfortunately for many species, alcohol preservation fell out of favour due to ...


5

tl;dr although basenjis are an "ancient" dog lineage and although they live in an area that has never been part of wolves' geographic range, they are thought (like all other dogs) to have originated in Asia by splitting off from wolves, after which their ancestors migrated to Africa sometime around 15,000 years ago. Domestic dogs are thought to be ...


4

DNA sequence is what we call a string of nucleotides in the DNA polymer, such as GATTACA, representing a chemical structure wherein each letter ("G", "A", "T", "T", "A", "C", "A") represents a nucleotide that has a chemical bond to the next nucleotide. Possible nucleotides in DNA are ...


4

As a point of order, the existence of DNA was demonstrated first by Miescher long before these terms came up (around 1870). He called it "nuclein" but he pretty fully characterized it chemically. However, it was not until the 1944 Avery-Macleod-McCarty experiment published in 1944 that DNA was shown to be the hereditary material. Now a partial ...


4

In this context, that symbol is read as "prime". "...a typical 5’—3’ order of appearance..." would be read "...a typical 5-prime to 3-prime order of appearance..." In organic-chemistry, these values are used as a systematic means to denote different Carbon atoms that are part of the same compound. DNA and RNA consist of a ...


4

Unlike RNA, where the sense of the molecule is unique, DNA is double stranded, with the two strands having the opposite sense. In the sense of chemical stability it odesn't matter, which sense is considered positive, and which is negative. Thus, if we consider a base pair step WX|YZ, we have Y folowing W on the positive sense strand (W->Y), and X ...


4

The first person to directly indicate a linkage between the hereditary material and enzymes was Garrod in 1902, based on the observation of the hereditary enzymatic disorder alkaptonuria. This is after Mendel's death. The tetranucleotide hypothesis (i.e. DNA is not informative) that you refer to seems to have been formulated around 1910. So there is no way ...


4

The different protonations forms are considered in the averaged Mw. Removing two H2O is the step that makes your average different than the traditional 650Da per base pair. But you must remember that the last base pair in the sequence will have it's OH group so you need to add 17.008 gr/mol * 2 = 34.016 gr/mol. The effect of this changes with the length of ...


4

If the query genome is unknown, a microarray cannot be made for a target species. Microarrays have DNA fragments of what you want to amplify on them. Those fragments must be known. From nature: DNA microarrays are microscope slides that are printed with thousands of tiny spots in defined positions, with each spot containing a known DNA sequence or gene. ...


4

First, I think you have misunderstood the concept of sense/antisense. These are defined individually for each gene, with the sense strand always referring to the coding (non-template) strand of a gene, and the antisense strand to its complement, the non-coding (template) strand. So in your plasmid example above, all genes are encoded by their respective ...


4

A genomic library is generated for the purpose of encapsulating the full genetic component of an organism. You do this by fragmenting the genome with restriction enzyme that cuts at its recognition sequence. These fragments are then taken and cloned into a plasmid, so that they can then be sequenced inside the plasmid using common sequences that are found ...


4

The answer to this question is very much no. Genomes are of arbitrary length and structural organisation (i.e. ploidy), so there isn't a fixed number of 'slots' that different base-pairs could inhabit (like e.g. rolling a dice). As a consequence (and as jamesfq mentioned in the comments), no matter what genome you have, you can always add additional levels ...


4

Meaning of Motif in Molecular Biology In English the word, motif (borrowed from the French), has a variety of meanings in different areas. The one that is borrowed in molecular biology is that of pattern together with a hint, perhaps, of emblem or badge. The word pattern indicates both repetition and a master mould from which copies are made. In molecular ...


3

It seems to me that "genic" is a perfectly good word. This paper uses "genic" directly as a contrast to "intergenic", so that seems like a reasonable precedent: ‘Noncoding DNA’ can be found both surrounding genes, and within genes (see schematic Figure 1). We will call the first type ‘intergenic’, and the second type ‘genic’, a ...


3

EF1-alpha is considered a ubiquitous/constitutive promoter; it is effective in all animal cells and tends to provide strong expression. Embryonic (and other) stem cells are more difficult to target than other cells because they don't express genes under the cell-type specific promoters that are often used for other populations of cells, which is why you're ...


3

I am not sure about apiculture, but in academic research it is typical that people use microsatellite markers for identifying subspecies of bees. Microsatellite are repetitive regions of the genome that are useful in at identifying different species/subspecies, as well as for generating pedigrees and paternity analysis. Different species/subspecies have ...


3

Yes, it was solved in the early 1960s, starting about 1961. See Wikipedia's Genetic Code - History, and perhaps "Establishing the Triplet Nature of the Genetic Code".


3

When describing mutations, $\Delta$ usually stands for deleted sequences. In this case it means the exchange of 4 cysteine residues in the NCAM protein by serines to disable palmitoylation and the association of the protein to lipid rafts. If you search for this specific mutation, you will find the paper from Niethammer et al., 2003, which describes the ...


3

In saline solution all the DNA ends up at the very bottom. Under centrifugation, the Caesium Chloride solution forms a density gradient, each DNA rises or sinks to the equivalent density. The same procedure is used with Sucrose solutions for other separations.


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