What causes some genes to be latent and others expressed?

Question

If I had a genetic mutation in my family, my uncle has expressed it, but my mom doesn't express it, but I have it and express it, then what would cause this? Is it really environmental to express a latent gene or is it like the lottery? I don't understand how a gene can turn itself off one generation then switch back on the next generation.

Answer 1

Some genes booze heavily and hibernate.
While the others - ex-pressed!

Answer 2

Typically genes come in pairs. Dominant and recessive genes. For example pair A a . If your mom has the pair A a and Dad has A a there is a chance you could end up with a a which means the mutant gene is expressed. Try looking up punnet square to help you work it out.

Answer 3

There are two parts to the answer. First, there are two types of genes, recessive and dominant. You get half your genes from each parent. If you recieve a recessive gene and a dominant gene, guess which gene shows its effect? The dominant. Only if two recessive genes combine, is the effect shown. Statistically, there is only 1 chance in 4 where recessive qualities are shown in the individual. Its kind of a lottery. Your mother probably didnt get the two recessive genes, while you and your uncle got them.

Then again, some qualities are exacerbated by the environment, but in a single family, the environment effect can be discounted, since the basic environment shared by the family members is similar.

Answer 4

We have 2 copies of each gene, one from our mum, one from our dad. The genetic mutation in your family sounds like it is recessive. This means that you need to have two mutated copies (ie a mutated copy from both your parents) for the mutated charcteristic/ disorder to show. Your uncle may have inherited two mutated copies from his parents, but your mum may have only inherited one mutated copy (so the mutation doesn't show). She would have passed this on to you and you would have had to inherited a second mutated copy from your dad for mutation to show.

Answer 5

it all has to do with the Punnet Square Grid.