mitochondria contain their own DNA, when tested for mom and dad, you can tell mom specifically. Why?

Question

females don't have Y-DNA
Male's have Y-DNA and M+Dna but only pass on Y-DNA

Answer 1

It's pretty easy if you think about it. You started as two cells, right? Egg and sperm. Only the egg has mitochondria, so you get your mother's mitochondrial DNA.

Meanwhile, since women are XX chromosome, and males are XY, you can only get a Y chromosome from one parent, your father. Women have their mother's and father's X chromosomes, while men have their mother's X and father's Y.

Answer 2

Both of those statements are true.

Y-DNA is the DNA found only on the Y-chromosome. So it's only in males.

mtDNA is the DNA found in the mitochondria. It's in all mitochondria, in cells of males and cells of females. However, only the mother's mitochondria are passed on to the offspring in the cytoplasm of the egg cell. So a child's mitochondrial DNA is entirely from the mother.

Answer 3

From the very source (Peter Sutovsky):
"Maternal inheritance of mitochondrial DNA has long been regarded as a major paradox in developmental biology. While some confusion may still persist in popular science, research data clearly document that the paternal sperm-borne mitochondria of most mammalian species enter the ooplasm at fertilization and are specifically targeted for degradation by the resident ubiquitin system. Ubiquitin is a proteolytic chaperone that forms covalently linked polyubiquitin chains on the targeted proteinaceous substrates. The polyubiquitin tag redirects the substrate proteins to a 26-S proteasome, a multi-subunit proteolytic organelle. Thus, specific proteasomal inhibitors reversibly block sperm mitochondrial degradation in ooplasm. Lysosomal degradation and the activity of membrane-lipoperoxidating enzyme 15-lipoxygenase (15-LOX) may also contribute to sperm mitochondrial degradation in the ooplasm, but probably is not crucial. Prohibitin, the major protein of the inner mitochondrial membrane, appears to be ubiquitinated in the sperm mitochondria. Occasional occurrence of paternal inheritance of mtDNA has been suggested in mammals including humans. While most such evidence has been widely disputed, it warrants further examination. Of particular concern is the documented heteroplasmy, i.e. mixed mtDNA inheritance after ooplasmic transplantation. Intracytoplasmic sperm injection (ICSI) has inherent potential for delaying the degradation of sperm mitochondria. However, paternal mtDNA inheritance after ICSI has not been documented so far."

Answer 4

???What is Y-DNA?? do you mean a Y chromosome?

Mitochondiral DNA is cytoplasmic DNA. The reason it's passed through the maternal line in humans and other primates is that the egg has cytoplasm and sperm does not. Not all animals pass mitochondrial DNA through the female line only. For instance, Sea Urchins inherit cytoplasmic DNA form both parents.

Answer 5

Sperm have a lot of mitochondria, which they need for the energy burst necessary for their trip to the egg. But none of them enter the egg when the sperm contacts the egg. All that is left is the mitochondria already in the egg, which came from the mother.

The Y-DNA is from the nuclear DNA that enters the egg.

Answer 6

Because Y chromosones contain little useful genes besides those for male characteristics. The X from the mother contains the most information, and many genes that can be traced specifically to the mother.