system
Given the following post, respond as if you're commenting on Reddit:
human
Are genes from Mom/Dad just a coin flip at every "zip" of the DNA sequence? How far away can we deviate from 50/50?

People often say we are "50% of Mom, 50% of Dad", wouldn't we actually be some amount above/below, like maybe I'm 45/55 and my sister would be 57/43, my brother maybe 49/51, etc? I assume there is some point like 30/70 which cannot be achieved, do we know of such a point existing (are we all a minimum of 40% one parent, or 35%, etc)?
gpt
You contain 50/50 from your mom and dad. It's essentially a coin flip at each of their genes, which you got: your dad might an allele for brown eyes and an allele for blue eyes, and you are guaranteed to have received one or the other from him. Same as with your mom. But 50% of your genome came from each.

What you express is based on which gene is dominant or recessive. If you got your mom's red hair gene, but your dad's black hair gene, you'll express black hair. You still contain both genes.

What you can't guarantee is that you'll be 25% of each of your grandparents, because of the randomness of which genes from within your parents you received.