Tag Archive | 23andme

23andme Basics and an Update

My favorite capabilities at 23andme are: finding new relatives with DNA and comparing them in the chromosome browser, looking at my ancestry composition in depth, and having the ability to look up specific genes. Most of the recent changes at 23andme are to the ancestry composition tools, specifically there is more granularity in the areas it shows for your ancestors’ origins.

With three generations of Munsons on 23andme, thanks to my niece’s recent test, I can finally evaluate the GrandTree. This tool, found on the Family & Friends menu, lets you look at what you inherited from each grandparent. Not surprisingly my niece LM got way more from my mother, whose mother she strongly resembles, than from my Dad. There is no guarantee that you will get exactly 25% from each grandparent. In my case, I got more from my maternal grandfather which I deduce from my 28% jewish ethnicity.

This tool will look at the traits and health items tracked through the generations even if you did not buy the health reports. This will be discussed in more detail later in this article. Meanwhile, I will do a quick review of the current 23andme basics as a guide for my niece and any other new testers reading this.

Finding DNA relatives and comparing them in the chromosome browser

Click on DNA relatives on either the Ancestry menu or the Family & Friends menu to look at your cousin list. Here are my previous posts on this topic, still fairly accurate:

Looking up a specific gene

You can look up a specific gene or marker in the Browse Raw Data function which is found on the menu under your name. Click here for my blog post about the AIDS resistant gene which details how to  do that type of look up.

Ancestry Composition

The great thing about the ancestry composition display at 23andme is that it shows you the details by chromosome. None of the other testing companies do that. What’s more if you put your cursor on a specific ethnicity, it will highlight just those segments on the diagram. Click on Ancestry Composition on the Ancestry menu to get to the page with the most details, including the chromosome by chromosome display.
Continue reading

Are you genetically resistant to AIDS?

There is a gene called CCR5 that can have a variation that prevents AIDS. You need to have two copies, one from each parent, to be immune to AIDS. If you have only one copy, your resistance is increased. The current theory is that this mutation became prevalent in Europeans after the ravages of smallpox or perhaps the Black Death and was selected for, since it is presumed protective against those diseases. It is more frequent in Northern Europe than Southern, but is found as far south as North Africa.

from wikipedia – By US National Institutes of Health – National Institute of Allergy and Infectious Diseases – US National Institutes of Health – National Institute of Allergy and Infectious Diseases, Public Domain, Link

The down side is that this CCR5 change may increase your risk of an abdominal aortic aneurysm and put you at risk for complications from various viruses like West Nile or tick born encephaliitis. Wikipedia has an excellent and detailed article about CCR5 here.

This AIDs protective variation is actually the loss of 32 alleles (so it is called delta 32) on chromosome 3 at location 46414947.

It is that change that the Genetics researcher He Jiankui claims to have made on two embryos in China using CRISPR technology which has caused such an uproar around the world. Click here for the NPR article about that which mentions that their father is HIV positive.

If you have tested your DNA at 23andme, you can check your own CCR5 for the delta 32 variation which is known as i3003626 there. Here’s how

Continue reading

Finding Cousins at 23andme

There are a number of posts on this blog which can help you navigate 23andme (click here) but as always in life, things change. Now there are many new features and ways of finding information that are not covered by those articles. Plus the tests sold during the holiday sales are coming in and I have lots of new cousins.

The Family & Friends page – red arrows show what to click to get to the DNA relatives list from either top menu or this page

The key to using your 23andme test for finding new cousins is to navigate to the DNA relatives page and then click on each name of interest to go to the page with information about that match. The contents of that page are well covered in my previous blog post (click here)

Most importantly, you can get to the version of the chromosome browser that shows the actual segment locations and sizes from that match page. Here is why that is important.

When a new tester matched me, my dad, and several distant cousins for 33cM on a specific location on the X, I knew she was related via the Fatland farm family from Halsnøy island, Hordaland, Norway, because I had previously identified the ancestral source of that segment from the 1700s (click here to read about that). It took me a little over an an hour using Ancestry’s possible parent clues to build her a tree and find her descent from that family. It helped that I knew what I was looking for and only one of her Norwegian lines was from the Hordaland region.

23andme does not do tree matching for you like Ancestry does, but it does provide a chromosome browser. This means that sometimes you can tell from the segment that a cousin matches you on who the likely common ancestor is. When you keep a large master spreadsheet of all your matches from all the companies, this can sometimes be quick and easy (click here to read about using spreadsheets for DNA ).

Continue reading

23andMe News: A Sale and New Features

There is a Valentine’s Day Sale at 23andme.com for American users, $20 off for up to two kits until Feb. 14 which brings down the price for the ancestry only version to $79, more in line with the other companies.

In other news, rumor has it that non-American users will finally be transitioned to the new experience in the next few months. If anyone from 23andme is at Rootstech this week, I will ask for more specifics on that.

Meanwhile there are several new features at 23andme for those of us, Americans, on the new experience:

  1. The automated triangulation feature now shows all DNA relatives, not just open sharers, and includes anonymous users with a link to request a share.
  2. Ancestry composition includes a timeline indicator making a guess as to when your ancestor with that ethnicity might have lived.

Click the read more for the details on these. I confess, I am at Rootstech right now, so not there is not much time to write about these in depth, just a few thoughts and images.

Continue reading

Ancestry Composition Numbers by Segment at 23andme.com

Did you know 23andme now provides the segment data for its ancestry composition assignments? This is a pretty recent feature and might even be useful. Unlike the other companies, 23andme does its admixture (aka ancestry composition) in chunks. This may make it more accurate than the others but in any case it means that they can give us the segment numbers. Then we can compare those to our matches.

To get these numbers, first pull down the reports menu and click on ancestry. On the initial ancestry page click on Ancestry Composition or the > symbol next to your highest group. Both are marked with my red arrow below.


The next page, the ancestry composition page has the pretty chromosome picture with ancestries displayed where you can change the confidence level from speculative (50%) to conservative (90%). To get a CSV file of the segments you click on Scientific Details at the top or the bottom of this page.


Then scroll all the way to bottom of that next page until you see this. You can select your confidence level as well for your downloaded data.


Continue reading