is being black a recessive or dominant gene?

Answer 1

The skin pigment melanin is present in most races. The degree to which it is expressed correlates to latitude of the environment, the selection process is a scale of vitamin D deficiency if you were too high a latitude and dark, to skin cancer of you wer at a low latitude and light.

So you could say humans come with a built-in sunscreen that can be dialed in to the optimal SPF over a few dozen generations.

The caucasians that migrated to india are a case in point.

Answer 2

There are many characteristics that are associated with race, but no real concrete definition of race, and few characteristics that are contained solely within a race. As a result of this, the exact line where you say "this person is black" or "this person is not black" is largely (but not completely) arbitrary. And if you can't even define what it means to be black in the first place, it's going to be a lot harder to figure out which genes are involved as well!

One thing we CAN talk about with some confidence is skin color, if you like. Pretty much all the color in peoples' skin is produced by cells in the skin called 'melanocytes'... these prodce pigments called (predictably enough) 'melanin'. There's two kinds of melanin that can be made: one is red to yellowish in color, and the other kind is dark brown to black in color.

The exact color and the amount that is produced by melanocytes is controlled by around five different genes. Each of the five different genes comes in a variety of types, not just two, and none of them are dominant or recessive. Instead they all operate pretty much all the time. Here's how that works:

Some genes kind of control simply whether you can do something at all. If you have one working copy of a digestive enzyme, you produce some. You produce the broken copy too, usually. If the broken copy doesn't do anything, we say it's a recessive disease because if you have two broken copies you have no working enzyme and that's a problem. If, on the other hand, the broken copy causes problems, we say it's a dominant disease because having only one copy will cause problems.

Well skin color is no disease. But the same thing happens. No matter what you have, you produce both. If you have red pigment genes and black pigment genes, your skin will have both red AND black pigment, though you may have trouble seeing the difference. If you have two black ones you'll make lots of black pigment, if you have one you'll make about half as much, and if you have none you won't make any. Since there are a half-dozen genes involved and lots of variations, you can see how this can easily produce the cornucopia of colors we see in people everywhere!

Hope that helps! Black or white, you're people-colored!

Answer 3

There's no "black gene" or "white gene." What makes a person appear more black or white is based on many genes which control what features they have. Some are dominant and some are recessive. If a black person and a white person have a child, the child will have a combination of features associated with both races, they will not have either a white or black baby (which would be the case of only one gene was responsible.)

Answer 4

It depends on what you mean by "black." If you mean "of African American descent," then blackness is mathematically governed. If both parents are fully African American, their offspring will be also. If one parent is African American and one parent is caucasian, the child will be "half black." And so forth, just like if we were talking about being Italian or Chinese. On the other hand, if you are talking strictly about skin color, it is governed by between four and six genes that have incomplete dominance. In this situation, the different genes contribute different amounts of melanin, the pigment that darkens skin, and when different genes are passed onto the child, the skin color is intermediate between those of the parents; incompletely dominant genes are neither dominant nor recessive.

Answer 5

Skin color is not controlled by a single loci recessive vs. dominant mechanism. You can tell this because of the broad range of skin colors, which include almost all intermediate values.

Answer 6

it is a collection of genes... but for a single gene it should be dominant because one copy of the gene is enough to give a phenotype