San José State University
Thayer Watkins
Silicon Valley
and Tornado Alley

The Problem of Missing Genes
from a Mixed Female Ancestor

I was told that my great grandmother was half Cherokee and thus I am one-sixteenth Cherokee. For a number of reasons this delighted me. When I got my DNA analyzed through 23 and Me I was expecting confirmation of that ancestry but I was disappointed. 23 and Me told me that I am of 99+ percent European ancestry.

I have great confidence in 23 and Me so I was perplexed. There is a problem historically with the matter of Cherokee ancestry. The Cherokees freely adopted nonCherokees into the tribe. For example, the Texas independence leader Sam Houston was an adopted Cherokee.

Perhaps my family was wrong in the belief that my great grandmother, Molly Green, was half Cherokee. I have found other people puzzled by DNA analysis not confirming family beliefs concerning great grandmothers.

I was especially fond of claiming Molly Green as a half Cherokee ancestor because of a bit of history. There were two migrations of Cherokees out of the Southern Appalachians. The famous one occurred in the 1830's at the instigation of President Andrew Jackson and settled the Cherokees and four other tribes in a place called Indian Territory which later became the state of Oklahoma. But there was an earlier one in the early 1800's. Two Cherokee towns in Eastern Tennessee got into a bitter dispute concerning territory. They called upon President Thomas Jefferson to settle the dispute. He offered to transport the residents of one of the towns to territory west of the Mississipi River that later became the states of Missouri and Arkansas.

Jefferson's solution was accepted. However the Cherokees were transported to isolated settlements with no communication between them. Later a Cherokee leader named Benjamin Green set about establishing links between the Cherokee settlements.

After the 1830's migration the earlier migrants and their descendants were known as The Old Settlers.

It was easy for me to believe that Molly Green was a descendant of Benjamin Green so I definitely wanted Molly Green as an ancestor. But I thought 23 and Me was telling me something different.

That is not the case. The answer is very simple. Molly Green had two X chromosomes. One X chromosome was from her Cherokee parent and one was from her nonCherokee parent. Luck had it that the X chromosome she passed down to my later ancestors was the nonCherokee one. So I am a descendant of Molly Green but not really genetically Cherokee. So my personal characteristics that I attributed to Cherokee ancestry, such as dark tanning, came from different sources.

Upon consulting with a friend who is professionally knowledgable about DNA analysis I found that women do not typically pass on unchanged to their children one or the other of the X chromosomes they receive from their parents. Instead they compose new X chromosomes from their two X chromosomes.

He also informed me that 23 and Me is not infallible. They may not have enough Cherokee DNA to establish Cherokee ancestry.

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