The number of copies per nanogram of DNA is going to depend on the size of the mitochondrial genome. I'm assuming you mean mammalian so it's about 16.5 kb. If you are using a mixed DNA extraction with both nuclear and mitochondrial DNA, then there is no easy way to know. In general, there are many mitochondria in a cell, and each mitochondrion has many copies of the mtDNA. Depending on the tissue type, this could be 10-10,000 mtDNA/nDNA. Mitochondrial DNA is also less sensitive to degradation over time so it's the easiest to test for from ancient samples and/or crime scenes.
The number of copies per nanogram of DNA is going to depend on the size of the mitochondrial genome. I'm assuming you mean mammalian so it's about 16.5 kb. If you are using a mixed DNA extraction with both nuclear and mitochondrial DNA, then there is no easy way to know. In general, there are many mitochondria in a cell, and each mitochondrion has many copies of the mtDNA. Depending on the tissue type, this could be 10-10,000 mtDNA/nDNA. Mitochondrial DNA is also less sensitive to degradation over time so it's the easiest to test for from ancient samples and/or crime scenes.
Hello, Asmaa.
Typical somatic cells have 1,000~2,000 mitochondria per each cell, and each mitochondrion has 2~10 copies of mtDNA. So, a typical somatic cell has minimum 2,000~ maximum 20,000 copies of mtDNA.
For typical diploid somatic cell, we have 2 copies of a specific gene per cell. Nuclear genomic DNA and mtDNA will be mixed in the ratios of minimal 1:1,000~maximal 1:10,000 in isolated DNA solution. This means that the template fragment you targeted for PCR are present 1,000~10,000-fold higher than that of genomic DNA.
Since 3.6 pg DNA/cell, 1 ng DNA is calculated as 278 cells' DNA (~300 cells). Therefore, the number of mtDNA copies would be about 300(2,000~20,000)=0.6 million~6 million copies of mtDNA.
0.6~6 millions mtDNA copies are present in the isolated 1 ng DNA of diploid somatic cells.
That is amazingly high number. Still, a haploid human oocyte has 0.1 million mitochondria unlike somatic cells. This makes 'African Eve' story!!!
--- Misconceptions about mitochondria and mammalian fertilization. Proc Natl Acad Sci U S A. 1996 Nov 26; 93(24): 13859–13863.
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