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MitchellSince1893
11-05-2013, 03:51 AM
I may have stumbled across something pertaining to 23andme's Global Similarity Map feature. Then again, I may be way off base.

My theory is 23andme has me more Irish than either my mother or father because I have the red hair/fair complexion gene and they do not.

Just a little background from their website:

"In this map, each icon or colored square represents a person. The closer two people are on the map, the closer they are genetically. You can see how close you are to populations from around the world and to your 23andMe connections, all at once."

When I got my test results I came out solidly in the Irish area. I was somewhat surprised based on my genealogical research. I thought I should have been in the English block. According to my research, on paper I should be approximately 40% English, 25% Scottish and Irish, 20% Welsh, and 15% German. Based on what you inherit, I understand that there will be a difference in the composition of one's genetic make up vs. one's genealogical background.

Fast forward a few months and my mother and father's results come in. They are both solidly in the English box with my mother being closer to the German side and my father closer to the Irish side. This matches my genealogical research for them. One would think I should be in the English box in between my parents. I'm on the left, father in middle, and mother on the right in picture below.

874


I then looked at my health results and saw that I have the red hair gene. At the MC1R gene I was:


rs1805007 CT
rs1805008 CT

I then looked at my parents results. Neither had this red hair combo but I think I can see how I got it.

Mother
rs1805007 CT
rs1805008 CC

Father
rs1805007 CC
rs1805008 CT

I'm a novice at this but I'm assuming I got my rs1805007 CT from my mom and my rs1805008 CT from my dad. This combo gave me red hair?

If I'm reading this right, then this may explain why 23andme has me way over in the Irish box. Due to this hair color/complexion gene I am genetically more similar to Irish than English.

FWIW, using the various admixture tools on gedmatch I don't see this Irish tendency. Also, when I got my McDonald results my center point was in the Netherlands (about what one would expect...in between Germany and Britain).

For comparison, 23andme's ancestry composition tool on speculative mode:
I'm 52.6% British & Irish, 6.3% French & German, 36% non-specific N European
Father is 53.7% British & Irish, 10.1% French & German, 32.5% non-specific N European
Mother is 47.7% British & Irish, 16.6% French & German, 28.6% non-specific N European


Let me know if there is a flaw in my logic or my understanding of gene inheritance.

AJL
11-05-2013, 04:20 AM
I believe they only use a small subset of ancestrally informative SNPs to do that map -- and it might include MCR1. My guess is that through sheer luck of recombination you happened to inherit from your parents most of the Irish and Scottish SNPs thet they use and much fewer German ones.

Recombination does odd things, as you mention. My mother is around the English Channel while my maternal aunt is solidly in the Irish section. Meanwhile my paternal grandfather is in the Middle East and I end up simultaneously in Austria, Poland, and Italy. That map was not bad in 2008 but I don't find it nearly as useful as Ancestry Composition or Countries of Ancestry.

geebee
11-06-2013, 02:35 AM
I then looked at my parents results. Neither had this red hair combo but I think I can see how I got it.

Mother
rs1805007 CT
rs1805008 CC

Father
rs1805007 CC
rs1805008 CT

I'm a novice at this but I'm assuming I got my rs1805007 CT from my mom and my rs1805008 CT from my dad. This combo gave me red hair?


Your assumption isn't quite right. Each of the letters in each pair came from a different parent. So it doesn't make sense to say you got the rs1805007 CT from one parent, and the rs1805008 CT from the other.

Yet you did get a C and a T from each parent. You inherited your rs1805007 T and your rs1805008 C from your mother, and your rs1805007 C and your rs1805008 T from your father. This ends up looking the same as what you said, but it isn't. In neither case did you get the combination from a single parent.

You're still essentially on the right track. Your red hair is likely the result of the combined effect of the alleles you inherited from each parent.

vettor
11-06-2013, 04:59 AM
my 23andme placings.........lower bottom of austrian square.

BTW........how do you see what SNP you have in 23andme

http://img809.imageshack.us/img809/4862/vfnm.png (http://imageshack.us/photo/my-images/809/vfnm.png/)

Uploaded with ImageShack.us (http://imageshack.us)

MitchellSince1893
11-06-2013, 05:20 AM
You inherited your rs1805007 T and your rs1805008 C from your mother, and your rs1805007 C and your rs1805008 T from your father.

Thanks for the clarification. If I understand correctly it would look like this?

MitchellSince1893
11-06-2013, 05:35 AM
BTW........how do you see what SNP you have in 23andme

There may be a more direct route but for this particular gene, I went into the health section, and clicked on melanoma.

I then clicked the technical report tab, which displayed a table showing my mother, father and my names in the far left column.
The column headers in the table were SNPs used, Genotype, Allele, and Adjusted Odds Ratio.

Obviously you have to have your mother and father tested at 23andme to see their results in this table. I identified them as such using a feature in the 23andme family tree feature.

vettor
11-19-2013, 08:20 PM
as per my chromosome depiction breakdown based on location.
Can I assume that since I know I have records of both paternal and maternal for last 9 generations ( for each) in North-East italy, that chr 2, 3, 7 and 10 at least represents this Italian part?

http://img853.imageshack.us/img853/2512/993i.png (http://imageshack.us/photo/my-images/853/993i.png/)

Uploaded with ImageShack.us (http://imageshack.us)

vettor
11-20-2013, 02:28 AM
as per my chromosome depiction breakdown based on location.
Can I assume that since I know I have records of both paternal and maternal for last 9 generations ( for each) in North-East italy, that chr 2, 3, 7 and 10 at least represents this Italian part?

http://img853.imageshack.us/img853/2512/993i.png (http://imageshack.us/photo/my-images/853/993i.png/)

Uploaded with ImageShack.us (http://imageshack.us)

since I posted this a few hours ago, it seem that now 23andme has updated my chromosome with an inclusion of 0.1% of north African and the french and german went up to 5.9% . .............must have been an upgrade of something at 23andme .................test was under Standard choice

Chr #6 where my Ashkenazi is is only under my North European section .............that is, ALL #6 has NO South European...is this normal?

MitchellSince1893
11-23-2013, 03:39 PM
Vettor,

My composition percentages have stayed the same...at least in speculative mode. I read on another thread that 23andme was in the process of updating their ancestry composition populations.

I cannot answer your questions about your chromo 2, 3, 6, 7, and 10.

Tolan
11-23-2013, 07:25 PM
my 23andme placings.........lower bottom of austrian square.

BTW........how do you see what SNP you have in 23andme

http://img809.imageshack.us/img809/4862/vfnm.png (http://imageshack.us/photo/my-images/809/vfnm.png/)

Uploaded with ImageShack.us (http://imageshack.us)

Thank you for posting your map because I did not know it existed on 23andme!
Here is mine.
To see the SNP chomosomes tested, click on the top right of the page, in your name, and select "browse raw data"

960

vettor
01-03-2014, 11:25 PM
since I posted this a few hours ago, it seem that now 23andme has updated my chromosome with an inclusion of 0.1% of north African and the french and german went up to 5.9% . .............must have been an upgrade of something at 23andme .................test was under Standard choice

Chr #6 where my Ashkenazi is is only under my North European section .............that is, ALL #6 has NO South European...is this normal?


Running with the setup CONSERVATIVE and Chromosome view, I noticed it filtered out the "newest" ancestry split and gave me only Italian at 1.6% on Chromosome #20. This was about 30% of the bar.

It also gave me 50% of the X chromosome as Italian

I have no other portions of percentages allocated to anyone else or any other continent.

Does this indicate my line is very old in Italy? or ......?

AJL
01-03-2014, 11:55 PM
Running with the setup CONSERVATIVE and Chromosome view, I noticed it filtered out the "newest" ancestry split and gave me only Italian at 1.6% on Chromosome #20. This was about 30% of the bar.

It also gave me 50% of the X chromosome as Italian

I have no other portions of percentages allocated to anyone else or any other continent.

Does this indicate my line is very old in Italy? or ......?

Probably, though both Italy and all areas around it are undertested, so it is hard to be confident.

Dimanto
01-30-2014, 07:10 AM
http://s20.postimg.org/p41rg0b61/Me_and_mum_cluster.jpg (http://postimg.org/image/p41rg0b61/) The green flag is my mum.