New Addition to Family DNA Project

I neglected DNA analysis last year but am determined to spend more time on it this year.  Taking the SLIG course, Genetic Genealogy, in January was the first step.

Secondly, I am proceeding with visual phasing of my siblings and I.  This is proving more challenging than expected, but I am slowly making progress, all the while dodging coronavirus carriers and rooting on national unity.  Using the spreadsheet developed by Steven Fox, I uploaded the DNA for three siblings from Gedmatch.com and have set all the recombination points.  I am now assigning grandparents to each segment on each chromosome, but some chromosomes are problematic.

Part of the problem is that we don’t have a lot of close cousin matches on my father’s side, at least on Gedmatch, so it is proving hard to figure out whether a segment is paternal or maternal in some cases.  The closest match on my father’s side is only 53 centimorgans (cMs).  This could be a relationship that is anywhere from 3C to 7C and I don’t know the exact connection.  (I suspect it’s from my Blalock line, which only goes back to 2GG.)  I have one more match at 50 cMs and a bunch in the 30s.  The bottom line is that none of my siblings and I have paternal matches in Gedmatch who are 1C or 2C.

However, I just learned that you can use cousins with an unknown relationship as long as you know whether they are paternal or maternal.  So that will help.  Anyway, this is ongoing.

In the meantime, I am happy to announce that a new member of our family has joined our DNA project.  For privacy reasons, I will refer to him as Bifrost.

Bifrost is a first cousin to Sibling Set 1.  His shared cM totals with this set of cousins are all in the 800s.  He is most closely related to Jelly Bean at 883 cMs, followed by Nurse Betty (871), then Fjordster (855) and lastly Valhalla (830).  However, these differences are not great and since the average amount of cMs that first cousins share is 866, we can see that these are all healthy, middle-of-the-bell-curve amounts.

On the other hand, the genetic relatedness of Bifrost to Sibling Set 2 is far more varied.  These are the children of Jelly Bean, and thus are his first cousins, once removed (1CIR).  Bifrost is most closely related, first, to Bizzy (563), and second, to Jonnesy (508).  Both are above average amounts for the 1C1R relationship.  According to the Shared cM Project 4.0 Tool,^[1]Blaine T. Bettinger, “The Shared cM Project – Version 4.0,” March 2020, www.thegeneticgenealogist.com, CC 4.0 Attribution License., 1C1R relationships share 433 cMs on average, so 563 cMs is definitely above average.  His relationship to JazzMa at 391 cM is a bit below average, while his relationship to Boyboy at 308 cMs is decidedly low.  It’s so low that if we didn’t know their true relationship, we would guess they are more likely to be half 1C1Rs (54%) than full 1C1Rs (36%).

Within Sibling Set 1, the closest genetic relationship is between Valhalla and Fjordster; the most distant is between Fjordster and Nurse Betty.  Within Sibling Set 2, the closest genetic relationship is between Boyboy and JazzMa, although Boyboy and Jonnesy are right on their tail and practically the same (2892 and 2878); the most distant is between Boyboy and Bizzy.

Siblings on average share 2613 cMs – thus, the siblings in both sets tend to share more cMs with each other than the average family.

This new addition to the family adds credence to my hypothesis that Bizzy possesses more Norwegian DNA than any of her siblings.  Bifrost is half-Norwegian because his mother is my Norwegian grandfather’s sister.  Our genetic connection, therefore, is wholly Norwegian in origin.  Once completed, my visual phasing project will eventually answer this.

A first cousin to Sibling Set 2 should be joining the project soon, so there will be more to report then.