I would say I’ve done an above average amount of reading about ancient history. I do wish I had studied this in post-secondary school however that’s a whole other topic. Two things I remember reading about that just seemed weird and creepy were how in the Jewish culture, you were only considered Jewish IF your mother was Jewish and pharaohs married their sisters to keep the blood-line pure which researchers believe lead to genetic problems.
My DNA has been with Ancestry for quite some time and I also sent my DNA into 23andMe. Because I could download my raw DNA data from Ancestry, I also sent the raw file into FamilyTreeDNA and MyHeritage. (I may have sent it into Gene too, I’ll check this later). In 2007, I sent my DNA into the Genographic Project which was part of National Geographic.
It’s expensive to belong to all these 3rd party genealogy companies, so I chose Ancestry and 23andMe to maintain my membership, while also paying FamilyTreeDNA $10 to get some extra detail.
Recently I’ve been trying to get my head around genetics and genealogical DNA and I just finished The Family Tree Guide to DNA Testing and Genetic Genealogy (2nd Ed.) by Blaine T. Bettinger. It was very interesting as the author lays out the differences in all the 3rd party companies, what they offer and reveal, most of which is WAY over my head.
What I gleaned from the book is that all the 3rd party companies have their pros and cons, but 23andMe seems to come out on top for lay-person level data analysis while FamilyTreeDNA is a step above lay-person, hovering almost out of touch for me.
But following is a summary of what I learned about DNA and I write all the below in an effort to galvanize the information into my own brain.
A cell has 23 pairs of chromosomes: 22 autosomal pairs plus a “sex” pair (either a XX pair for females or a XY pair for males). These chromosomes are all INSIDE the nucleus of the cell.
The mother passes along her X-DNA to ALL her children, either pure from her mother or by jumbling up her father’s X with her mother’s X. There is an 85% chance that it’s jumbled.
The father’s X-DNA (either pure or jumbled from his mother) is passed to his daughters who cannot pass it on to their children.
The father’s Y-DNA (chromosome) is only passed down from father to son, unchanged, exactly as it was going back eons. Meaning a man’s Y-DNA is the same as his father’s, grandfather’s, great-grandfather’s, all the way back to “Adam”. Also meaning you can’t tell which genealogical level it comes from. Example: Two men have the same Y-DNA. I can’t tell if its because they are brothers, first cousins, nephew/uncle, etc. Women do NOT have a Y-DNA so cannot pass a Y-DNA down to her children. Therefore, the Y-DNA will disappear in the line IF there are no sons, or said to have “daughtered out”.
The mt-DNA (mitochondrial), which is found OUTSIDE the nucleus of the cell, is only passed down from the mother to ALL her children and like the Y-DNA, it is passed down unchanged, and like the Y-DNA you cannot determine genealogical level, all the way back to “Eve”. Even though a man will receive his mother’s mt-DNA, he cannot pass it down to any of his children. Therefore, the mt-DNA will disappear in the line IF there are no sons, in essence “sonned out”.
This leaves the 22 autosomal chromosomes (or at-DNA). 50% of one’s autosomal DNA comes from the mother and 50% comes from the father. With every generation, the autosomal DNA matching gets halved. Therefore, autosomal disappears over time, meaning, the further away a match is shown on Ancestry or 23andMe, the less sure it is. Once you get past the 3rd or 4th cousin, there’s only a small percentage of matching DNA. Example: Siblings will show a 50% match. First cousins will show a 25% match. Second cousins will show a 12.5% match and third cousins will show a 6.25% match.
That being said its the autosomal DNA that reveals loads about the full ancestry of a person, because you potentially have a little bit from every ancestor in your tree, or potentially have nothing from an ancestor because it got filtered right out.
Example:
My life-partner, Lorne, is 100% Ashkenazi Jew. Our daughter, Meghan, is 50% Ashkenazi Jew. But Lorne would not have passed down his Y-DNA to her nor any of his mt-DNA from his mother. Therefore, Meghan shows 50% Jew solely from Lorne’s at-DNA and from his X-DNA (jumbled or pure).
Now for my conspiracy theory. Is it just a coincidence that the ancient Jewish people and the pharaohs set up rules surrounding the pureness of their children’s bloodline?
If a pharaoh had to have children with his sister, than would mean the Y-DNA, X-DNA, mt-DNA and at-DNA would all be 100% and pure.
By my calculations, if siblings always have a son and a daughter, who marry, and then the incest continues:
- Y-DNA is always transferred to the sons; never “daughters out” as long as there are male children
- X-DNA from the father never stops as it is passed down through the daughters
- X-DNA from the mother never stops as it is passed down through the sons
- mt-DNA stays pure, as it wouldn’t matter if it jumbles, and is always passed down
- at-DNA stays at 100%
In royalty, the daughters are often married to male cousins, when INCEST became scandalous and a very bad idea.
In the Jewish faith, the mother needing to be of Jewish blood before you can say you’re Jewish because the mother passed down the mt-DNA 100% and the mother’s X-DNA (which can be a jumble of mom’s X and dad’s X) is passed down to daughters 100%.
My question, why would the female DNA be more important than the male DNA which holds the all-important Y??
Answer: Because in the Jewish faith, its the man who chooses a wife to bare his children. The man is Jewish and Y chromosome will be passed. But he MUST choose a Jewish wife for mt-DNA and the X-DNA to be passed. The Y-DNA will lead back to Adam and the mt-DNA will lead back to Eve.
This comes back to my initial conspiracy theory/question: How did they know? I cannot believe these traditions just came out of no where. Is it in the bible?
