Question

How can traits "disappear" and then "reappear"?

Answer 1

"The inheritance of traits is determined by genes which are long stretches of DNA that are passed down from generation to generation. Usually, the genes are made up with a coding part and a non-coding part. It is the coding part of the gene which determines the functional output, whereas the non-coding portion contains switches and units that determine when, where and how much of the functional output should be generated.

Some genes are dominant and some are recessive, and it is the dominant gene that produces the trait.. it is always there but if another more dominant gene is also there then it will be dormant.For example, if a trait is produced by a recessive gene, one of your parents may be a carrier but not possess the trait (because she inherited a dominant gene that overrode the recessive one). However, when her genes were recombined to produce the ovum from which you grew, and when that combined with your father's DNA, the trait may resurface.

Traits 'skip' generations because most traits are not accounted for by a single gene, but by their combination with other genes. There is no brown hair gene, or blue eye gene. These traits may be controlled by recessive genes, so they seem to skip a generation from grandparent to you."

Answer 2

Traits can disappear because even though they are still in the genes, they are just not expressed. Take a person, and the gene will be eye color. So they inherited a blue color allele from their mom and a brown from their dad. And in they have brown eye color. So the brown eye allele is dominant and tends to be expressed, and the recessive allele isn't. However later on, especially if the person has a family with another person with blue eyes for instance, the opposing are likely to have blue eyes, so the allele reappears.

Answer 3

Thank you both!

Answer 4

cool beans :)