Problems with 23andMe Ancestry Composition

If You’re Korean, That Is….

Does your 23andMe DNA results say you are Japanese or Chinese?  If this is confusing to you then please read.

Note:  This article was written in response to posts from highly confused Korean adoptees and other 2nd and 3rd generation Korean-Americans whose DNA results showed their “Ancestry Composition*” as being Japanese and/or Chinese. Across the board, 23andMe has the ancestry composition of Koreans to be as much as 35% “Japanese.” Who could blame them for being confused, It’s confusing even for those who aren’t adopted to see such results. 

*(Incase you’re not familiar with, they have a feature called “Ancestry Composition”. As described on 23andMe, “Ancestry Composition tells you what percent of your DNA comes from each of 31 populations worldwide. This analysis includes DNA you received from all of your recent ancestors, on both sides of your family. The results reflect where your ancestors lived before the widespread migrations of the past few hundred years.”)

These are “sample” Ancestry Compositions taken directly from the 23andMe website to explain this. Ironically enough, among some of their examples include “Example Chinese Person” and “Example Japanese Person.” If you’re Korean, it would be reasonable enough to expect that your results would look something similar to these examples. Right? Well guess again.



이모의 AC

THIS  is a what a typical ancestry result of a Korean person looks like. This is my aunt’s (mother’s cousin 5촌) ancestry composition. She is absolutely Korean.

Here is my story: Having a layperson’s knowledge of both Korean history and knowledge of my family (I am not adopted), I was shocked to find that nearly 1/3 of my East Asian regional composition and nearly 1/2 of my brother’s was Japanese! There is absolutely no way my family is 30-45% Japanese! I even double checked with my mom who was adamant about the fact we do not have a drop of Japanese blood, let alone a third! (OK, I will admit there’s probably a few drops here and there, but definitely not anything close to 45%…or even 20%!)  To fully understand your DNA results, you need to understand Korean history…..not a whole lot, but even just a little.

My family has been in the same area in Korea as far as their family records go. Now this is where the history part comes in.

(Please note: I’m not going to attempt to cram in 5,000 years of history.  This is going to be as high level as it gets. It’s what the average Korean person who was raised in Korea already knows. Please consider this simply an entry point for further exploration.)

Sample Korean Ancestry Results

This is my uncle’s ancestry composition, who is completely and utterly Korean. Interestingly, this is one of the LOWEST percentage of Japanese that I’ve seen compared to other Ancestry Compositions that I’ve seen.

Most of the area in the Southern part of Korea where my family is from (today’s Jeolla-Do) sits in what was the kingdom of Baekje. Most of the area in the Northern part (today’s North Korea and parts of China/Manchuria) was another Korean kingdom called Goguryeo. There was also another competing Korean dynasty called Silla. Together they made up what is known as The Three Kingdoms.

Ancient Japan (known back then as “Wa” 왜(倭)) was a very isolated place made up of various warring ethnicities/tribes. In the eyes of the ancient Koreans and Chinese, the ancient people of Wa were considered barbaric and uncivilized. In around 367 AD, the Korean kingdom of Baekje took one of the tribes under its wings and helped them to unify all other tribes as one Japan. Baekje sent its politicians, scholars, doctors, artists, artisans and fighters to maintain stability and to quickly bring them up to speed with the rest of the civilized East Asian society. Baekje even introduced Buddhism to Japan. For hundreds of years Baekje and Japan had a very tight “Big Brother/Little Brother” relationship. The daughters of Baekje royalty and nobility were sent to Japan to marry their nobility with the goal of tightening the bond between the two even more and having future Japanese emperors through Baekje mothers. In return, Japan provided additional military protection against Baekje’s neighbor, Silla.

This relationship lasted until the fall of Baekje in 660 AD by the Silla/Tang Alliance (Tang was a Chinese dynasty). After the fall of Baekje, many took refuge in Japan which was thought of as a better alternative than to be absorbed by the enemy.  In 2001, Japan’s emperor Akihito told reporters “I, on my part, feel a certain kinship with Korea, given the fact that it is recorded in theChronicles of Japan that the mother of Emperor Kammu was of the line of King Muryong of Paekche.” ¹  (btw – Paekche is an alternative way to spell Baekje). For more reading on this part of history, check out and excerpt from the book “Ancient Korea-Japan Relations: Paekche and the Origin of the Yamato Dynasty”  by Wontack Hong, Professor Emeritus at Seoul National University.

Over the course of next 1400 years, there were a lot more interactions, but it would take volumes to go over every detail, so let’s just fast forward to modern history. Japan colonized Korea in 1910. Leading up to this time around the 1870’s, Japan made great efforts to be looked upon by the rest of the world stage as superior to Korea. Much of this was done by distorting Korean history by either inserting themselves into Korean history or deleting Korea’s contributions to Japan’s history.  Japan succeed in getting the rest of the world (America and Europe) to believe they were the dominant people, hence they were allowed to take Korea with no objections from the West.

Up to and through the Japanese colonial period, Pro-Japanese Korean traitors sent their children to Japan to improve their own positions. Many of them took Japanese names and married into Japanese families.

Around 1920 Japan experienced a major labor shortage, so thousands of Koreans moved there to escape the dire poverty they were facing Korea under Japanese colonization. By 1930 Koreans were considered a major recognized group in Japan. During World War II, around 700,000 Koreans were forced to go to Japan to fill wartime labor shortages in factories and farms and another 200,000 Koreans fought in the Japanese Imperial Army. By 1945 there were around 2.5 million Koreans in Japan.

Now I’m not suggesting that Koreans have 100% pure Korean blood, there’s no such thing. There’s no such thing as 100% Japanese or Chinese either. But for Koreans across the board to have such high amounts of Japanese seems awfully suspicious to me. The median percentage of Japanese DNA is about 30% whereas the median percentage of Chinese DNA is about 10%. Keep in mind that Korea and China actually share a land border which has moved around lot over the past 1000 years; whereas Japan is at its closest point is about 200 miles away from one another.

Therefore, I would argue that the so-called “Japanese DNA” they have found in Japan is in fact KOREAN DNA. Same goes with China. The Chinese Government (DPRC) recently (starting in the 1990’s) started making claims that Goguryeo is actually Chinese history and even call the people of Goguryeo a Chinese “Minority Group.” (however, I think most Chinese people recognize it as a part of Korean history). With that said, because of constantly moving borders over the past thousands of years, the lines are a bit fuzzier when it comes to what is Korean DNA versus Chinese DNA. I suspect the more north your family was originally from, the higher the Chinese DNA will be. But when it comes to Korean and Japanese DNA, you need to be a geneticist to see that something’s just not right.

This is disturbing on many levels.  For starters, there are a lot of adopted Koreans who have no idea what their DNA results means and now think they are part Japanese or Chinese. There are also non adopted Korean-Americans who know nothing about Korean history who are also confused. Most importantly, there’s an ENTIRE SCIENTIFIC COMMUNITY who are mislabeling the Korean people.

Japan won’t admit they were ever under Korean wings and that Korean DNA is littered throughout Japan. The Japanese want the world to believe that it’s THEIR DNA that has been spread throughout Korea, not the other way around. They won’t even allow their royal tombs to be examined in fear that it will turn up to be buckets full of Korean blood!

Here’s another example of actual ancestry results from my 2nd cousin (6존) – My mom’s cousin’s child, who is very much Korean.

We need to encourage 23andMe, as well as the entire the scientific/genetic community to take these factors into account rather than “assume” that just because similar DNA was found in Japan, we MUST all be Japanese. They need to look at historical facts and actual evidence rather than blindly accepting Japanese revised version of history (which by the way, is the version we are taught in the West).

I suspect the average Korean person in Korea does not even realize this is happening because: A) DNA testing is new for most everyone, especially for Koreans in Korea and B) Koreans in Korea have no reason to do a DNA test because they know who they are and where they came from. Therefore, it us up to us Overseas Koreans, Mixed-Race Koreans, Korean Adoptees, etc to spread the word since we are those ones who are doing the DNA tests. We need to encourage scientists and geneticist to help educate the rest of the world and to set this right, because no one else will.

So despite what your ancestry composition says, rest assured: YOU ARE KOREAN!!!

I encourage you to share this and post your thoughts. 🙂

Sources: 1 2 3 4 5 6 7 8 9 10 11 12

Additional Thoughts (Part 1:

I did a bit more research to validate an assumption. There are several international genetics groups such as HUGO (Human Genome Organization, The International Conference of Human Genetics (ICHG) established in 1956; The International Congress of Genetics (ICG) which has been meeting since 1898 (Tokyo was the host city in 1968) and is a part of the International Genetics Federation (IGF). Below is the membership roster of the other international genetics body HUGO (Human Genome Organization).

If you explore any of these organizations, you will see that Korea has never had a seat at the international genome table, which is exactly as I suspected.  When one doesn’t have a seat at the table, they will never get the chance to be heard nor the opportunity to defend their position.

Australia 2 Austria 1 Belgium 2 Canada 11
Denmark 2 East Germany 1 Finland 1 France 15
Greece 1 Israel 2 Iceland 1 Italy 2
Japan 11 Norway 2 South Africa 1 Spain 1
Sweden 3 Switzerland 4 The Netherlands 7 United Kingdom 33
U.S.A. 103 USSR 5 West Germany 9 Total 220

Additional Thoughts (Part 2): X Chromosomes:

Let me start by providing a very high level and brief overview about X chromosomes. Males have only an X chromosome which comes from their mother. Females have both an X chromosome from their mother but also a Y chromosome from their father. Now, when looking at the chromosome view within 23andMe, you’ll see that if you are a female, you will have two X bars. One of those bars is from X and the other Y.  Males will only show one X bar.

Korean x-chromosomes

Chromosome View on 23andMe’s Ancestry Composition. These are examples from two Korean males. As you can see, they have primarily, if not all Japanese labeled X Chromosomes.

In looking at ancestry compositions through the “chromosome view” of countless people who have shared their results with me, I could not find a single Korean male with X Chromosomes labeled as Korean. They were all labeled either 100% Japanese or primarily with the remainder being general “East Asian”  or a tiny bit of Chinese. As for females, only the Y Chromosomes showed partial Korean DNA.

I can’t even fathom a legitimate scientific explanation for why Korean males have absolutely no Korean X Chromosomes, nor have I been able to find any explanation for this.

Seven Prong Sword of Baekje (백제 칠지도). This sword was given as a gift to the State of Wa (present day Japan) in the 4th Century. Baekje served as a major cultural and political influence to Wa (Japan). The last original copy remains in Japan.

Seven Prong Sword of Baekje (백제 칠지도). This sword was given as a gift to the State of Wa (present day Japan) in the 4th Century. Baekje served as a major cultural and political influence to Wa (Japan). The last original copy remains in Japan.