What is the "Ashkenazi" gene? Genetic testing

amother

Violet

Sun, Jul 24 2016, 6:14 pm

I recently did 23andme and a significant portion of my ancestry came back Ashkenazi. When I click on that, it just says,

"Ashkenazi Jews are thought to have settled in Central and Eastern Europe about 1,000 years ago. DNA shows clearly the connections among those who consider themselves to be Ashkenazi Jewish: two Ashkenazi Jewish people are very likely to be "genetic cousins", sharing long stretches of identical DNA."

But this test doesn't say where the Ashkenazi gene originated. I know what our own tradition is, but what is the Ashkenazi gene exactly? I've heard talk that our DNA is close to Greeks, some say Palestinians, etc. But does anyone here actually know and have scientific sources? I'm honestly surprised that 23andme starts at Ashkenazi ppl settling in Europe. Yeah, I know we did. :/

Raisin

Sun, Jul 24 2016, 6:36 pm

All ashkenazi Jews are descended from a very small group of people who settled in Europe at some point. Specifically in the area called Ashkenaz - France and Germany. From there, some Ashkenazim moved east to Poland and Russia, others to other parts of Europe.

We also share DNA with sefardim and other Jews, (and some non Jews) but have a lot more DNA in common with each other.

I don't think there is an ashkenazi gene, is there?

amother

Lavender

Sun, Jul 24 2016, 7:22 pm

There is an ashkenazi panel of test that can be done to see if you are a carrier of a particular genetic disease. If both husband and wife are carriers of the gene, they are at risk of having a child with the disease. If only one parent is a carrier, it does not pose a risk.

I, for instance am a carrier of the genetic disease called "Goucher" but my husband is not so we don't have anything to worry about.

When one does Dor Yesharim, you don't go through all of the tests that are available today and you aren't given results either. I happened to re-do the bloodwork and the extensive ashkenazi panel before doing IVF to be sure. That is how I know what I am a carrier for, although as I mentioned earlier, it isn't an issue for us as my husband is not a carrier.

You can google the list of ashkenazi genetic diseases. There are some lists out there.

Good Luck!

amother

Lavender

Sun, Jul 24 2016, 7:23 pm

amother

Scarlet

Sun, Jul 24 2016, 9:38 pm

My grandparents on both sides are from Russia/Poland but I look very Sephardic. I've been mistaken for Arab, Indian and Hispanic among other things. I'm not sure how I got "Sephardic genes" but we do share the same ancestors!

Amarante

Sun, Jul 24 2016, 9:43 pm

I read it awhile ago but as I recall the Ashkenazi descended from a relatively small group of men who settled on Europe and married local women. Because of this, it's an incredibly small gene pool relatively speaking because the community was fairly insular in terms of intermarriage.

As I recall, it is one of the reasons, the group is often used as a way of testing genetic theories.

As I recall Israel is considered t be one of the centers of genetic research. It may be chicken or egg since Ashkenazi do have some very specific genetic diseases within a small population and therefore it interests Jewish scientists.

I could be misremembering this as I had read about it awhile ago when I was check get specific genetic traits after I had some blood work done as blood groups are associated with population groups as well. The bad and good of the Internet is that you start reading about one thing and then start following interesting hyperlinks.

Simple1

Sun, Jul 24 2016, 9:47 pm

amother wrote:

I don't know about the ashkenazi genes. But in general, for some genetic issues, a gene can be passed down with only one parent being a carrier.

Amarante

Sun, Jul 24 2016, 9:55 pm

Simple1 wrote:

I don't know about the ashkenazi genes. But in general, for some genetic issues, a gene can be passed down with only one parent being a carrier.

Depends on whether the gene carrying the diseases is dominant or recessive.

I believe most of the Ashkenazi genes are recessive or else the incidence of these diseases would be much higher and also why genetic testing is so important for couples to make sure both parents don't carry the recessive gene.

Some diseases like Huntingtons Chorea are dominant so if inherited from the parent, the child will always get the disease. This is not an Ashkenazi specific disease.

amother

Royalblue

Sun, Jul 24 2016, 11:03 pm

There is no such thing as an Ashkenazi gene.

A person has about 20,000 genes. Each gene is string of a few thousand DNA letters. Most of the letters are identical between two people but every person will differ one from the other in a small number of DNA letters.

Those letters that are different give a person their genetic uniqueness. Among close family (you, your parents, kids, even cousins), you are bound to share more of those unique letters. Among people of the same racial / ethnic bacground, you will share more of those unique letters than you will with people in the general population.

But these unique letters are in the same 20,000 genes that everyone has. It's just the unique letters that make you look more Ashkenazi.

amother

Violet

Mon, Jul 25 2016, 12:24 am

amother wrote:

Thank you so much for explaining that. I think I understand.

Regarding the diseases more likely for Ashkenazim, I came up negative for that on 23andme but I already knew that since I had done a similar test previously.

amother

Royalblue

Mon, Jul 25 2016, 5:00 am

Skippy!! wrote:

There is a kohen gene: http://www.aish.com/ci/sam/48936742.html

As this Aish summary explains, the researchers looked at DNA segments that ALL men have (not just kohanim). They identified patterns that were generally common among kohanim. (And to be very technical, they weren't necessarily looking at genes.)