SomeGuy
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Just a question about genetics: blond hair is a recessive gene in humans, and I'm curious - how many generations can blondism "skip"? That is, if two babies are born, both of them the kid of a blond and of a Native American say, then they'd both be carrying the dominant black hair gene and the recessive blond hair gene. What then, if these two kids eventually got together and had a kid? From what I know of grade 11 biology, there is a 25% chance that the kid of these parents would be given two 'bb' genomes (or whatever they're called), and hence, be born a blond. Is that correct? I mean, I just can't imagine a half-blond and half-non-Caucasian mating with the same, and giving birth to a blond kid. I have half-black/half-white friends at work, some of whom had blond fathers, and yet I just can't see these dark-skinned people having blond kids. (When someone is half-black they're always quite dark.)
What have I misunderstood here? Is it that hair colour / skin pigmentation is determined by something more complex than just one genome (or whatever those Bb Tr things are called)? Or can dark people have blond babies? :?: I'm confused.
Thanks for your help, if you can offer any.
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| SomeGuy
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If you can't answer this question, but know of a better website to ask it on, please tell me. Thanks.
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| beiwen
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I'm not sure either. However I would think about codominance characteristics regarding with skin and hair colours.
It may be simpler to deal with eyes-colours. Blue is recessive, brown is dominant. However, I think, grey or green ar the result of two codominant genes like a light-brown with a blue eyes gene coming together.
Remember that exercises on genetics always intend to simplify the questions to give a gross idea about the way genotypes come out to be finally represented by fenotypes.
Many times, one characteristic is not given by a gene but by a group of genes. That is to say, it may need more than one protein to be synthetysed. [/b]
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