Saturday, January 21, 2017

Segmentology and the X chromosome- a theory

It isn't hard to find references to "sticky" DNA or inheritance of segments in blocks on blogs today. And almost all of the experts will tell you not to use the X chromosome for analysis and confirmation of relationships. I am not a hundred percent convinced that we should avoid it entirely though.

I don't know the reason for the affinity of some DNA to stick around in larger segments over several generations. Is it because within those SNPs is a sequencing that is more preferential, or is it a factor of genetic dominance? I really don't know. And maybe someday I will become more educated and understand the why better. For now though, I don't need to know the why.

There is definitely prevalence for large inheritance patterns in the first 22 chromosomes on both of my parents, mostly my mom, but what about the larger DNA segments on the X chromosome? Is there a way of looking at the amount of DNA and guessing the location of the generation it comes from? I am not sure, but I would like to try and find out.

The X chromosome is funny. For one thing, men only have one, so they pass what they receive entirely to their daughters. But the mom's well they can pass it along in all sort of ways. I have seen one analysis in one blog where one of the X was passed as whole for several generations. Which is why I think they say don't look at it. My daughter got 2/3 of her X chromosome from me from my father, and only 1/3 from my mother. Something I think that explains a great deal in why she has so much less Native DNA in admixtures. A lot of my mom's Native DNA is on her X chromosome.

Looking at my father's X, he (well we) share a rather large segment in common with several descendants of  our McCurdy family and a few others. I have been trying to pinpoint a common X donator between two of those others to give me a clue on the mother of my ancestor Barsheba Collins. How did I pick her? Well, if you don't know how to tell your X donators, there are some excellent blogs, but basically it goes like this.

If your female, your X donators are your mother and your paternal grandmother. If your male your donator is your mother. It goes back from there in the same pattern.

My father's mother was Evelyne Virginia Hardy. Her mother was Lula Bell Pyburn, and her paternal grandmother was Talula Johnson. Lula Bell's mother was Plina McCurdy. Her paternal grandmother was Mary Jane Chitty. I don't know Talula's mother, but her paternal grandmother was Elizabeth Parker. Plina McCurdy's mother was Amanda Beck, and her paternal grandmother was Barbara Sunday.

Each of the other McCurdy's share the same pattern back to Barbara Sunday, and only one of them has Amanda Beck. Which means for the side I know I have to look at Barbara Sunday. We don't know her paternal grandmother's full name, but she was born in Europe, which doesn't look like the likely candidate since the others all have trees firmly in America, most specifically Georgia. So Barbara Sunday's mother was Barsheba Collins. That's how I got to her.

Looking at the amount of DNA depending on the company, your X is around 196 cMs. The segment I am looking at is 40 cMs, so not a small segment. Which in theory should mean, it should be closer, well, in my theory anyway. So can I take that 40 cM and look at the amount and possibly look at a number of generations?

My mom and her father's first cousin share 89 cM on the X chromosome. In this case, the cousin is female, so her entire X chromosome from her father came from her mother, Margaret Trahern. Mom's entire X from her father came from Bonnie Adams, a daughter of Margaret Trahern.

Though the inheritance patterns stick around longer on the X, I would think that it may be reasonable to assume that siblings on average share 25-75 percent of the X, but that range in theory could be 0. In terms of cMs then 46-140 cM's, with the possiblity (rare?) of 196 cM's.

I am going to probably not make this very clear, but I propose that all of your first x donators be generation 1, then all of their x donators be generation 2, and so on. Instead of a deduction by 50 percent, since the rate of change is slower and only one parent recombines, I did 25 percent. I also added a 10 percent anomaly range because well, X inheritance is funny. I would be interested to know if this theory of ranges pans out in triangulated matches as an approximate average.

Generation Number for your X donator
Maternal (X donator)
Paternal (X donator)
Proposed range cM
Additional 10 percent for anomoly
1 See note
Father’s mother (female)
Grandmother and mothers paternal grandmother
Paternal grandmother’s mother and paternal grandmother’s paternal grandmother
Grandmothers mother and paternal grandmothers mother and her paternal grandmother
Paternal grandmothers mothers mother, and so on …
28-78.5 cM



  Note: There are rules for this range.
1. Sisters will share entirely one X chromosome that they inherit from their father. They can share a possibility of  none (in case of non recombination) to 100 percent on the Chromosome they get from their mother.
2. A brother and a sister would share none to 100 percent of their X from the mother.
3. Two Brothers also would share none to 100 percent of their X from the mother.
4.  Paternal females first cousins will always match their grandmother's X at 196 cM's but may not match each other at that high of a rate, (it would be the same as brother to brother).

I have edited this to include the clarification above and this explanation.
I was corrected on my chart by another researcher who cites non recombination as up to 3 percent in occurrence on the X chromosome. I have read several scientific articles however that show the recombination rate on the X is 0.8 percent with three hot spots where recombination is likely to occur. That is the reason I gave a proposed range of 25-75 as an Average for siblings. Someone way smarter than me gave a statistical math formula for the inheritance of the X. That blog is here.

 In the case of both my parents, the table holds true for mom's and for Dad's, it's accurate for their common ancestor, and most likely DNA contributor as the source. I looked into two more, one for each parent, and it would seem that the range is a good place to start looking. For example, my mom matches her mother's sister at 61 cM's which is within the range for 2 on the chart. Note due to recombination, I do not match my great Aunt.

Dynastic relationships among the Choctaw

If there were truly dynastic relationships among the Choctaw of the late 18th and early 19th century then who were they?

Let's begin with the traders themselves. Among the earliest traders established in the Choctaw nation by 1773 were Benjamin James and Thomas James, cousins from Virginia. A Spanish Census in 1881 shows the presence of Alexander Frazier, Cornelius McCurtain, John Turnbull and Jesse Wall. We know also at this time there was Nathaniel Folsom and his two brothers, Edmond and Ebenezar Folsom, William Riddle, John Jones, Samuel Jones, and Thomas Jones in the Eastern district. 

By 1787 we have the following (I believe an incomplete) list of  traders (Simon) Favre at Yanabe, Louis at Outanoula, Chastang at Yazoo Loukfata and Petit Baptist at Bitabogoula all within the Eastern district. In the Western district there were Alexander Frazier with three employees at Yazoo, Louis (Favre's mulatto) at Cushtusha, Louis Leflore at Caffetalaya, the Pitchlynn Brothers (Isaac Pitchlynn) at Tchanke and Moses Foster at Mougouloucha. In the Chickasaw nation there was Louis Durant, Hardy Perry and John Turnbull. It is likely around this time Zadoc Brashears came to the territory. Charles Juzan began trading in the Southern district around 1788. Records involving the American Revolution and it's effect within the Spanish Mississippi territory also show the presence of James Welsh and James Cole.

Susanna Vaughn the wife of Zadoc Brashears is believed by many researchers to be the illegitimate daughter of John Turnbull and Winifred, who later married Thomas Vaughn and had several sons. The early prominence of the Vaughns in territorial records and treaties suggests to me that they are associated with a prominent Western district Choctaw. Given the wane of their influence after 1805, I highly suspect that Winifred was a female relative of Franchimastubbee. The Vaughns appear to have resided southeast of current Jackson, Mississippi. If the Vaughns appear to fade from influence, the Brashears do not. Primarily I believe, because of the intermarriage of the Brashears within other prominent family lines. 

Simon Favre married a daughter of Franchimastubbee in the late 1780's, and due to his influence with him, historians have long suspected the same for Turner Brashears (a distant cousin of Zadoc). 

When I look at the possibilities for the father of my ancestor Peggy, and her four siblings (both full and half), the most likely candidate I hypothesize is Thomas James. From his familiarity with Franchiamastubbee in his letter of 1792, a relationship with a female relative (I suspect possibly a sister of Apuckshunnubbee) may truly be indicated. Add to that the prominence of Molly and her family as recipients in the treaties of 1820 and 1830, and I think the theory has some good points. If he was in fact in partnership with his kinsman Benjamin James, the relationships of both men would have cemented trade relationships with all the major districts within the nation. Benjamin James with a woman of Shakihuma connections in the Eastern District, Thomas James with Nahotima of the Kunsha and the mother of Molly and her two sisters, relatives of Apuckshunnubbee and Franchiamastubbe. 

Four of these women would produce children that would influence the Choctaw in many ways. Molly's son James L. McDonald, Robert M. Jones (whose mother name we don't know),  Sally first wife of Middleton Mackey and mother of most of his children, and Peggy, the mother of Pierre Juzan and my ancestor James N. Trahern. The marriages of the Juzan's and Mackey's with other elite mixed bloods perpetuated the interconnections for another two generations.

If at one time I accepted the theory that Shumaka was a relative of Apuckshunnubbe, I no longer do. Records that indicate the location of Apuckshunnubbee in 1820 and 1830 when compared to the location of Shumaka lead me to believe, along with a letter from Coleman Cole, that the influence of Shumaka's son Robert Cole was not because he was a relative. It is rather, I believe, related to his position as a Shakihuma. Louis Leflore married two granddaughters of Shumaka, while his brother Michael married a Choctaw we don't know her family connections.

I have begun to suspect that Daniel McCurtain was an illegitimate son of Cornelius McCurtain and not his brother. His intermarriage with Hannah Cole, a daughter of James Cole and Shumaka is one of the many complex Yalobusha area relationships. The Perry's, Fraziers, and descendants of Shumaka have a complex series of marriages both in the Choctaw and Chickasaw nations. Though most believe the Perry's and Fraziers are seperate Chickasaw or Choctaw, I suspect that they share the Shakihuma heritage that the descendants of Shumaka have. The influence of the Perry and Frazier group is unique in that aside from the children of Benjamin James, and John Pitchlynn by his first wife, they are the only ones who receive land from both the Chickasaw and Choctaw.  

As I have mentioned before, Benjamin James family appears to have a dual citizenship status similar to that of the Yalobusha families. We also know that both the wives of Nathaniel Folsom had kinship with the first wife of John Pitchlynn, and that they were considered Choctaw and Chickasaw, suggesting that they too were Shakihuma or another tribe with similar status. It is no secret to any who know Choctaw history that the Folsom and Pitchlynn family have a large place in history.

Ebenezar Folsom and William Riddle both married daughters of Homomastubbee. Ebenezar's daughter, Sophia is the second wife of John Pitchlynn, her half siblings are the children of John Kincade and her mother. At one time I had thought that Edmond's wife may be a relative, but I don't any longer. I do suspect that Edmond Folsom also  married into a medal leader's family, but who isn't clear. It is quite possible based on proximity on the Armstrong rolls that the wife of Edmond Folsom was related to the mother of the Hall children.

The Jones brothers all intermarried and resided in the Eastern district. Robert M. Jones' father was most likely a son of John Jones. And here is where the foundations of the first generation begin to strengthen, as an Okla hannali elite married a Okla Falaya elite. It is a pattern we see for several generations among families with the surname Leflore, Folsom, James, Pitchlynn, Kincade, Riddle, Nail and Juzan. I forgot to mention the Garland family of Kunsha familial connections, or the Gardner family, whose ancestry we don't know.

The next time you look at a book on Choctaw history, and you read the names, realize that who they were was often as important in their prevalence in history.