Are the factors that create black skin colour genetically dominant over white skin colour?
The general rule for mixed race children is that they will be darker than the light parent and lighter than the dark parent. The difficulty with the prediction is the purity of the subjects. Because either parent may have mixed ancestry, even generations back, you cannot be sure what genes they're carrying. So you get a much more varied genetic expression. I suppose if you took a scandinavian parent and an african parent, the children would be much more constant.
Reply:Not even worthy of an answer!
Reply:I find it quite puzzling that since it is now thought that human life began in Africa, how we have so many white people in the world!
After all, if the black gene was dominant, it would long since have displaced the white gene, and absolutely white could not come out of any sort of mix.
Pity that we are so concerned about skin colour, but whites want to be a sunburnt brown and in the Philippines (and likely elsewhere too) darker skinned people want to be white!
We should all be satisfied with what we are, and enjoy our differences!
Reply:Skin colour is boring. Who cares? LoL!
Reply:A very interesting question!
I have a friend, who is a 'thorough bred' white Englishman. He married a Chinese girl while we were together in the forces in Singapore. They had four children (three girls and a boy), all born here in the UK (all have Herefordian English accents, by the way) and they all consider themselves English. The mysterious thing is that they ALL 'look' Chinese. None of them look 'English', after their Dad.
Does that mean that Chinese genes are 'stronger' than English genes?
Reply:My friend's mom is african american and her dad is white(irish). She has whiter skin than i do and freckles, the only thing she got from her mom was cheekbones and the untameable hair. Black is not dominant and neither is white, it's actually a coin toss. My friend maya's dad is dark(south indian) and her mom is white(north european) and maya is white, her brother is as dark as her dad, and her second brother is in between. It really just depends.
Reply:I though twe were beyond skin colour.
Reply:Brown eyes and brown hair are dominant genes, but skin color is the result of many genes, so there would be a variety of colors among the children's skin tones.
Reply:As far as I know (I may be wrong), skin colour is not genetic. Skin colour of offspring tends to be a blend of the parents' skin colours. Exposure to the sun influences melanin levels, which change skin colour, so that is another factor.
Although skin colour isn't genetic, the same principle of the gene pool could apply. For example, dark-skinned individuals may stand out in African grasslands, and so, they may be preyed upon by predators. This reduces the number of dark-skinned individuals in the reproductive group, which influences the skin colour of that group's next generations.
Reply:i think its a genetic advantage as melanin in the skin protects us from UV
Reply:I think yes, though I'm not sure. The 'black skin color' and brown eyes, black hair etc, is the result of a gene encoding for the presence of melanin protein in the body. The more efficient the gene, the more melanin present in the body, the more darker the hair and eyes and skin.
In white people, the gene for melanin is not very active, the reason why their hair are lighter, skin is lighter, and the iris/retina pigment of the eye is lighter (ranging from brown, to blue to green, to gray etc).
I think in a mixed race couple, the more efficient Gene would likely pass on to the children, though of course according to Mendel's laws we can predict that a small fraction of say 1 in 10 would be perfectly white, (using the 9:3:3:1 ratio, that is the one which considers all the manifestations of a gene ) while others would have a mixed color. They could have blue eyes with dark skin/hair etc.
Genes are not easily predictable. you never know which gene went where during fertilization, and you never know whether it was counter-ed by another or not.
So this is all I can tell you, although I'm sure I haven't completely answered your question.
Reply:" I'm guessing none of them will have blond hair and blue eyes and none of them will have white, northern european type skin colour. "
My nephew is mixed and has blond curly hair, blue eyes, and light brown skin. I have meet his dad's family and none are mixed.
Reply:The plants Mendel used had only 1 gene locus to control flower color, so co-dominance and/or dominance/reccessiveness of the flower color was easy to understand. Human skin, eye, and hair color on the other hand is much more complex. The current estimate is approximately 5-10 genes that are involved in determining the skin tone of an individual. Some of these genes can be turned on or off in utero, and so skin color is extremely variable among the offspring of parents with different skin tones. I think that the genes for darker skin are generally dominant to those for lighter, but not always. Light skinned individuals with dark skinned ancestors can have children with darker skin than their own.
