What kind of marker is generally used to detect total DNA content?

I do a lot of animal cells, I can give you a reference.

Animal genomes are generally shown in the 20 kb band (although this should be much larger).

Takara's 1kb Lader Marker up to 10kb, 1kb gradient;

The maximum band of the in-hindiii marker produced by Fermentas is about 21kb, but the maximum band is generally very bright;

Bands over 10kb are particularly small;

Therefore, it is recommended to use the in-hindiii marker and the 1kb lader to run electrophoresis at the same time. The marker itself will mark the amount of DNA, run out of electrophoresis and analyze it according to the brightness.

I've learned about it before, and I can only provide you with the following information.

There are two kinds of DNA markers commonly used now, one is obtained by enzymatic digestion of DNA such as viruses, and the other is a fixed value, such as 100bp, 200bp, etc.

Both markers are not difficult to make, for the first one, it is slightly more difficult, mainly to obtain large genome fragments such as viruses, and then use appropriate enzyme digestion, after the cutting is complete, you can get the corresponding map. The second is actually very simple, if you have any vector at hand, and its sequence is completely clear, then you can use the PCR method to obtain a series of fragments of different sizes, for example, the upstream primer can use one, and then use the method of counting to determine the downstream primer at 100bp downstream, the amplified fragment is the 100bp fragment, the primer at 200bp is the 200bp fragment, and so on, you can get a series of fragments of different sizes, after amplification, put them together, I got a homemade marker.

The DNA marker is available in 100bp, 200bp or other sizes. You can roughly estimate how much bp of DNA you want to measure, if it is very small, use 100bp, if you are unsure, you can run down the electrophoresis with 200bp to see how the result is.

Molecular markers are genetic markers based on nucleotide sequence variation in genetic material between individuals, which is a direct reflection of genetic polymorphisms at the DNA level. Compared with several other genetic markers, such as morphological markers, biochemical markers, and cytological markers, DNA molecular markers have the following advantages: most molecular markers are co-dominant, and the selection of recessive traits is very convenient; Genomic variation is extremely abundant, and the number of molecular markers is almost unlimited; At different stages of biological development, DNA from different tissues can be used for labeling analysis; Molecular markers reveal variations from DNA; It is neutral, does not affect the expression of the target trait, and has no association with the undesirable trait; The detection method is simple and fast.

With the development of molecular biology technology, there are dozens of DNA molecular marker technologies, which are widely used in genetic breeding, genome mapping, gene mapping, species kinship identification, gene bank construction, gene cloning, etc. An ideal molecular marker must meet the following requirements: (1) have high polymorphism; (2) codominant inheritance, i.e., the use of molecular markers to identify heterozygous and homozygous genotypes in diploids; (3) Be able to clearly identify alleles; (4) throughout the genome; (5) Except for the markers of special loci, the molecular markers are required to be evenly distributed throughout the genome; (6) selective neutral (i.e., no gene pleiotropy); (7) The detection method is simple and fast (such as the experimental procedure is easy to automate); (8) The development cost and use cost are as low as possible; (9) Good reproducibility within and between laboratories (convenient for data exchange).

However, none of the molecular markers discovered so far separate different biological DNA molecules are separated by electrophoresis and then hybridized to them with labeled, specific DNA probes to reveal DNA polymorphisms by autoradiography or nonisotopic chromogenic techniques.

Forget about copying and pasting, and it's not right to get a bunch of things.

DNA markers have different meanings in different fields. In molecular biology, it refers to the markers used to represent the length of DNA in electrophoresis, and in genomics, it refers to individual-specific genetic markers. I don't know which one you're talking about?

If you want to know more about a certain aspect, please feel free to ask.

Marker selection method during electrophoresis:

If it is a nucleic acid marker, it is relatively simple, that is, look at the relationship between the size of the marker band and your target band, and try to choose a marker with a target band close to the molecular weight, or a marker with more bands near the target molecular weight

In addition, if the target molecular weight is very small, and the gel usually chooses a large concentration, you should not use a marker with a large molecular weight, for example, if you only detect a 200 bp band, then it is more appropriate to use a marker with a molecular weight of up to 1000 or 500.

If the molecular weight is very large, for example in a few k, a marker up to 23k such as Lamda Hindiii may be chosenOtherwise, the gel concentration is not appropriate, and the marker bands will be inseparable, which will affect the judgment of the molecular weight of your target molecule.

In the past, we used the 2000 and 15000 markers the most in the laboratory, which can cover most molecular weight measurements.

The 100 bp DNA Ladder is a mix of 10 PCR amplified fragments.