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Author Topic: Race and Genes  (Read 2965 times)

Offline John.C

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Race and Genes
« on: 23/02/2007 13:03:53 »
I heard that white poeple have a lack of melanin (melanin causes the black pigment in the skin) which is known as hypomelanistic. The darker skin helps people handle the sun better. I also heard that black people don't produce Vitamin D as effectively as white people. If a white person and black person reproduce, is it possible the child could have the best of both worlds passed down? or perhaps the opposite and the worst of both worlds?


 

another_someone

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Race and Genes
« Reply #1 on: 23/02/2007 13:50:08 »
As far as I am aware, the only issue with production of vitamin D is as a direct byproduct of the sun protection - you literally cannot have one without the other, no matter what race you are.  Simply putting sun block on your skin will reduce your ability to synthesise vitamin D, since vitamin D is produced by the same ultra violet rays that are permeating through your skin from the Sun that you are trying to block out in order to protect yourself from skin cancer.  All that people with a darker skin have is a built in sun block factor.
 

Offline John.C

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Race and Genes
« Reply #2 on: 23/02/2007 14:15:24 »
Well, because the child would be brown (I guess) it would only be half blocked, not fully blocked like a black person and not unblocked like a white person. Does that make sense? Sorry if I sound stupid.
 

another_someone

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Race and Genes
« Reply #3 on: 23/02/2007 15:56:14 »
Well, because the child would be brown (I guess) it would only be half blocked, not fully blocked like a black person and not unblocked like a white person. Does that make sense? Sorry if I sound stupid.

A child of mixed race parentage can be any colour through the spectrum of the colours of its two parents, or anywhere in between.  The greater probability is that it will have a skin colour somewhere around the midpoint between the colour of its parents, but there is no certainty that it will be so.

Even more complicated will the colour of the grandchildren.  Even if the child of parents who are black and white, come out mid brown, and that child then marries someone who is black, their child may still be lighter than either of their parents, taking after the lightest of the grandparents (or, equally, if the mid brown child marries someone who is white, their child could take after the black grandparent).

If someone is mid brown, it will give them better protection against skin cancer, and less efficient production of vitamin D and folic acid than the white parent, but not so extreme as the black parent.  Whether this is an advantage or a disadvantage depends on the environment the child is likely to be living in (which is why white skin is an advantage in areas of the world with little sun, but a disadvantage in areas of the world with lots of sun - although with ever more of our lives being spent sat at a desk in an office, ever fewer of us see that much sun even in sunny climes).

I suspect the real problem most of us (at least those of us in the affluent world) have is that on a day to day basis we have too little sun for our daily vitamin D and folic acid requirements, and then we overdose on sun when we can, so exaggerating our risk to skin cancer without providing the regular doses that would benefit us.
 

Offline John.C

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Race and Genes
« Reply #4 on: 23/02/2007 16:01:10 »
Thanks for the great answer :)
 

jolly

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Race and Genes
« Reply #5 on: 24/02/2007 18:36:11 »
well it could be either, each child would be different from the next as is the case with all chrildren some would have the best of both some might not. all would probably benifit in different ways. Dont forget mutation which would also be a positive and negative depending on which you consider to be which. I think theres probably more positive than negative in that exchange though. If for no other reason than- people should get on better, mixing helps that process. but we should also mix in culture not just genes.   
 

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Race and Genes
« Reply #5 on: 24/02/2007 18:36:11 »

 

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