This year, microbiologists took a major step toward understanding the origin of eukaryotes, the group that includes plants, animals, and other organisms with cell nuclei.
And while most of your cells have their own DNA in the cell nucleus, mitochondria actually have their own genome in DNA, which is more similar to a bacteria.
While most of an animal's genes are contained in chromosomes located inside the nuclei of cells, the amh gene remains apart, floating freely within the cell nucleus.
Because they derive from bacteria that became symbiotic about 2bn years ago with cells ancestral to animals, plants and so on, mitochondria have their own DNA, separate from that in a cell's nucleus.
因为它们源自大约 20 亿年前与动物、植物等祖先的共生的菌,所以线粒体有自己的 DNA, 与核的 DNA 分开。