Dahyun week9

What can DNA tests really tell us about our ancestry?

Human genes are 99% identical. The differences between individuals occur in the remaining 1%.

Genetic testing can inform about paternity, but it cannot definitively answer whether one has ancestors from a specific region. There are two reasons for this. First, due to recombination during the process of meiosis. During the formation of gametes, base pairs mix through recombination. As generations pass, some parts inherited from one ancestor may be relatively more prominent, while parts from another ancestor may be relatively less so.

The genes received through recombination are unique, so even among siblings, the percentage of ancestry from a region, such as French, could differ significantly, with one sibling having 10% and the other 0%.

The second reason is the inability to precisely know an ancestor's genetic information. Identifying which ancestors' genes are included from a certain region is based on the genetic information of people currently living in that area. It involves looking for genetic markers common among the population of that region.

ref: https://www.youtube.com/watch?v=BIP0lYrdirI