Eli5: What are recessive genes? Why do we always get passed down genes that don’t show?
In: 5
So I’m going to simplify it even more than what some other people have said
Take a piece of paper and put one drop of light blue paint and one drop of dark brown paint next to each other. This is your dad and mom’s eye color.
You get half your genes from your mom and half from your dad. Your dad’s eyes are blue so all he can give you is a drop of blue. Your mom’s eyes are brown and she gives you a drop of brown. So put a drop of blue paint on the paper and then put a drop of brown paint on top of it. Which one is visible? The brown, because the brown is the “stronger” (i.e. dominant) color. But the blue is still there underneath the brown, right? That’s the recessive gene.
Now you have a child with a person who has blue eyes. But because of your dad you have a non visible blue gene to give. Your partner has ONLY blue genes to give, because clearly if they had a brown gene, they’d have brown eyes, right?
So you have Brown/blue and blue/blue. That combination can produce one either blue/blue or Brown/blue.
That’s the way recessive/dominant genes work.
Latest Answers