This question adresses a paxadoxon concerning genetic relationships: In textbooks, I read that DNA of man is 98 % identical to that of chimpanzee. Doing a genetic test at 23 and me revealed that I am just 49% related to my own father. How come?
Sites like 23andMe report percent relationships between people and that can help you identify relatives. For example, biological parents, children, and full siblings share about 50% (1/2); grandparents, grandchildren, aunts & uncles about 25% (1/4), and first cousins about 12.5% (1/8). But this is shorthand for the percent of DNA that varies within the human population. Almost all our DNA is shared in common (~99.9%). Think of genetic testing profiles like the Mendel inheritance charts we would make in high school bio. Estimates comparing humans to other animals or plants, are talking about all the DNA. Hope this helps, Maximilian. ~ Kevin
Kevin Wrote: But this is shorthand for the percent of DNA that varies within the human population. Almost all our DNA is shared in common (~99.9%).
Max: I still do not quite understand: genetic code consists of a sequence of base pairs in a certain order. If this order is identical, this means shared DNA, right? If certain base pairs in the order are different, this means "not related". So, which difference is between shared DNA between men and chimp and shared DNA between father and son?
Max
Similarity measures for DNA molecules depend on what you compare.If you compare coding regions for proteins (which are a minute amount amount of total DNA) you get the famous 98% ape-man similarity.If you compare total contiguous DNA which includes non coding regions that play important but not well enough understood roles in gene expression and regulation I bet you are much closer to your father and much more distant to the chimpanzeee,Finally if you compare SNP's in a population of human genes from various individuals you get other numbers for similariries
Thank you, Dikeos, this is now better understandable. But, honestly, it is astonishing that these different measures are not well seperated when communicated in the public!
Dear Maximilian
In the times we live it is very common to communicate to the public information which is not properly validated and described but is "sexy " enough to draw attention in the media and unfortunately also in textbooks,often serving politically
correct purposes.
- Badges
- Science topic
- Similar topics
- Biological Science
- Biochemistry
- Biomolecules
- Nucleic Acids
- RNA
- Small RNA
- microRNA