Will recessive genes eventually go away?

Question

This might sound like a stupid question. If there is a better chance for someone to get darker eyes or hair because darker colors are more dominant then wouldn't it be possible for recessive genes to go away? Because if the chance of darker is greater, more people will be born with them and if they have them not only are they dominant it will then be in their genes so its even a less chance their child will have a recessive gene unless the mom/dad has recessive genes. I'm bad at explaining but I hoped you understand where I'm coming from.

Answer 1

Its possible. Remember Ye Ole Punnet Square?

1st generation

    A__A      /      A__a      / a__a        / A__a     /

    AA /AA   /A/    Aa/aa  a/  Aa/Aa   A/  AA/Aa  / A

    Aa/Aa    /a/    Aa/aa  a/  Aa/Aa  A/     Aa/aa  / a

2nd generation

A__a        /      A__a          /

Aa/aa   a/       AA/Aa   A /

aa/aa   a/        Aa/aa    a/

And so on, it looks like my A isn't going to die out, but in theory recessive genes will fade and die out over time. In theory.

According to the Darwin awards, we should be getting smarter, but I haven't noticed any great increase of intelligence lately.

Answer 2

Population geneticist describe populations with the hardy weinberg principle.  The frequencies of genotypes are constant if certain criteria are met.  Given that assumption, recessive alleles never go away.  So there is an evolutionary advantage to having even a super small percentage of recessive carriers in case there is a large selection event and that homozygous recessive trait gives a selective advantage so the population doesn't go extinct.

Answer 3

they dont necessarily go away there will be a less chance. liuke if ur arenst both have A DD dominant. there is still a small chance very little that u can get recessive.

Answer 4

Not unless there is strong selection pressure against the the recessive allele. Just because an allele is recessive, doesn't mean that it is disadvantageous to carry it.

Even if an allele is selected against in individuals who are homozygous recessive, the recessive alleles can be maintained in heterozygotes.  

Answer 5

Recessive doesn't necessarily mean that it happens less often than dominant traits. That is more of statistics and numbers. Dominance and recessive-ness only influences the physical expression of the gene itself. For example, polydactyly, the presence of more than 5 fingers, is actually a dominant trait! Imagine that...if dominant meant more prevalent, then we'd all have more than a total of 10 fingers... Is that true though? Polydactyly is actually quite rare in today's society. Dominant doesn't mean more common and recessive doesn't mean rarer. Rarity is affected by natural selection. The only way for polydactyly to become prominent is that people actively looked for them and married them and had children with them that expressed the gene.

Answer 6

No because you're forgetting that all people carry two forms of the gene. Maybe two dominants or two recessives etc. Just because it is dominant doesn't mean it is more likely to be passed on. If you have blue and brown gene for eyes, your no more likely to pass brown than blue to your children. The only reason that people are more likely to have brown eyes is that depending on their combination,

Br Br   brown

Br Bl   brown

Bl Br   brown

Bl Bl   blue

They are just more likely to be displaying the dominant trait. But you can see, the recessive gene is still carried and has the same chance of being passed on to children as the dominant trait.