Are there some genes that are peculiar to certain races?

[twang]

For example are there genes that only native Americans, or Africans, or Europeans have? And can they be detected with DNA testing?

[darroll]

I used the National Geographic.
Haplogroups will show you where you came from.

[Yaffa]

Haplogroups on Y and MT DNA does go to one direct line ancestor and will tell you where they came from on only that one specific ancestor who has tested.

There are also some diseases that may be found in certain Ethnic back rounds.

You might want to be a little more specific on your question as to what specific information you are looking to find this way someone on the board can help you with what kind of DNA testing will help you.

[Helen]

For example are there genes that only native Americans, or Africans, or Europeans have? And can they be detected with DNA testing?

Yes (although strictly speaking the association is geographical not racial), they are called Ancestry Informative Markers (AIMs).

[Ann Turner]

No, literally speaking, there are no *genes* that are found only in one population. There are variations in genes (or other genetic markers between genes) that occur at different frequencies in various populations. These variants are called alleles.

There are just a small handful of markers that are completely informative, however (found in 100% of one population and 0% of another population). For the most part, the difference in frequencies are rather modest, maybe 60% of one population has a certain allele, 23% of another population, 39% of another population. For another marker, the numbers for an allele might be 7%, 49%, and 57%.

If you look at hundreds or thousands of such markers, you may begin to see a pattern.

[twang]

No, literally speaking, there are no *genes* that are found only in one population. There are variations in genes (or other genetic markers between genes) that occur at different frequencies in various populations. These variants are called alleles.

There are just a small handful of markers that are completely informative, however (found in 100% of one population and 0% of another population). For the most part, the difference in frequencies are rather modest, maybe 60% of one population has a certain allele, 23% of another population, 39% of another population. For another marker, the numbers for an allele might be 7%, 49%, and 57%.

If you look at hundreds or thousands of such markers, you may begin to see a pattern.

So with these differences in alleles geneticists will be able to tell if someone is descended from an Eskimo, or an African, or maybe an Australian aborigine?

[Ann Turner]

So with these differences in alleles geneticists will be able to tell if someone is descended from an Eskimo, or an African, or maybe an Australian aborigine?

Yes, with a couple of caveats.

1) You must have good reference data. The Human Genome Diversity Project has quite a few populations, but it was terminated (prematurely, in my opinion) for political reasons.

2) The process is most straightforward when all of your ancestry is from one region. Admixture complicates things.

[smith1]

I don't know about in other parts of the country but around here Smith's are usually red-headed and have freckles. Tucker's are usually very tall and dark headed. Williams are usually very, very athletic. Baldwin's are usually pot-bellied, bald, and kinda short. But that's just what I have noticed around my part of the country.

[Darren]

Please keep the topic related to genetic genealogy and try to refrain from generalizing a certain type of person or surname.

-Darren Marin
Family Tree DNA

[smith1]

Would you care to explain how that is not related to genetics?

[MMaddi]

Would you care to explain how that is not related to genetics?

This is the first sentence that you wrote above: "I don't know about in other parts of the country but around here Smith's are usually red-headed and have freckles."

I think it's a given that Smith is the most common surname in the U.S., or perhaps the second most common surname, after Jones. Do you really think that all Smiths in your part of the country are from the same paternal line, therefore somehow have inherited red hair and freckles from some ancestor in that paternal line?

For your statement to relate to genetics, that would have to be the case. And even if all the red-haired/freckled Smiths in your part of the country were from the same paternal line (highly unlikely), the y chromosome plays no role in hair color or whether or not someone has freckles. All the genes that determine hair color and whether someone has freckles are located on autosomal chromosomes, not the y. The autosomal chromosomes are inherited from all the ancestors, not just the paternal line ancestors.

So, merely because someone is named Smith in a large part of the U.S. there is no proven relationship to genetics involved in how they look.

[smith1]

so the redhair and freckles landed from outer space? The point is that everything genetic about us comes from someone back in the family tree. Some genes are DOMINANT. VERY dominant. And are "locked in" and spread throughout a family from one branch to the next and one generation to the next. I'm not crazy enough to think that ALL smiths are related or even that all of on particular surname are related in one area of the country. My point is that a large portion of them are. ANd those genes they carry all came from somewhere.

[MMaddi]

so the redhair and freckles landed from outer space? The point is that everything genetic about us comes from someone back in the family tree. Some genes are DOMINANT. VERY dominant. And are "locked in" and spread throughout a family from one branch to the next and one generation to the next. I'm not crazy enough to think that ALL smiths are related or even that all of on particular surname are related in one area of the country. My point is that a large portion of them are. ANd those genes they carry all came from somewhere.

What you're reporting is merely anecdotal and speculative. It doesn't reach the level of genetic science, just casual observations which may or may not be true. I think that was the moderator's point in his posting.

[rainbow]

What you're reporting is merely anecdotal and speculative. It doesn't reach the level of genetic science, just casual observations which may or may not be true. I think that was the moderator's point in his posting.

The moderator deleted my post before he posted. Unjustly, in my opinion.

[smith1]

It appears to me that anyone that asks a hard question or has a different opinion than the status quo around here gets there posts deleted or rebuked for having a different point of view. How can easily observed physical traits not reach a level of "genetic science" ? Isn't that what Genetics is ? Genes ?