Grandsons' atDNA Inheritance: A Case Study

If you are familiar at all with genetic genealogy, you know that children inherit 50% of their autosomal DNA (atDNA) from their mother and 50% from their father. You also may know that while children inherit about 25% of their atDNA from each grandparent, these amounts may vary.

I recently had the opportunity to compare the amount of atDNA shared by two of my grandsons with each of their four grandparents and with one great-grandparent -- father of their maternal grandmother:

	P-GF	P-GM	M-GF	M-GM	M-GGF
G-son A	1852.9 cM	1731.5 cM	1882.2 cM	1719.8 cM	727.2 cM
	25.8%	24.1%	26.2%	23.9%	10.1%
G-son B	2025.7 cM	1558 cM	1584.9 cM	2017.4 cM	885.4 cM
	28.2%	21.7%	22.1%	28.1%	12.3%

As you can see above, the percentage actually shared by each grandson with each grandparent varied from 21.7% to 28.2%. No big surprises there. We have long been told that after the first generation the amount of atDNA inherited is somewhat random and varies from one grandparent/grandchild pairing to another.

Note also that the amount inherited by both grandsons decreased by more that 50% between the amount they inherited from their maternal grandmother (M-GM) and her father (M-GGF). In this case the decrease seemed to be in proportion to the amount they had inherited from their maternal grandmother but I don't think we can come to any solid conclusions from this very small sample.

One thing did jump out at me that I had never though about before. As I mentioned above, it is well known that all children receive 50% of their atDNA from each parent. However, it had never occurred to me that all grandchildren inherit 50% of their atDNA from each pair of grandparents. While the amount inherited from each of the four grandparents may vary considerably, the amount inherited by the maternal grandparents combined or from the paternal grandparents combined will add up to 50%. It is a logical conclusion but not one that I had thought about before.  

Now I'm pondering to what extent this principle can be extended. For example, can we calculate how much atDNA my grandsons may have inherited from the mother of their maternal grandmother (M-MG). Can we conclude that each of the grandsons inherited 25% combined from the parents of their maternal grandmother? That would be useful, if true, because we only have DNA test results from one of the great-grandparents.

I'm still pondering how far, if at all, this bonded inheritance can be extended. Do any of you have data and/or thoughts? 

The Winning Innovators for 2017 Are

Last year a big portion of the $100,000 in cash and in-kind support from the Innovation Showdown at RootsTech 2016 went to TapGenes which has continued to develop its product and outreach for those seeking to organize and share family health information. 

This year 40 contestants from the US, Europe and Canada entered the competition. Ten semifinalists were invited to compete this week in Salt Lake City during  the world’s largest family history technology conference. In case you want to look back at those semifinalists now, you can look at my earlier post where the ten are listed with links to where you can find more information.

Judging focused on both the promise of the product as well as the soundness of the business model. Each contestant had two minutes to present the product. Then the panel of five judges had a combined two minutes to ask questions or make comments. If you are familiar with the television show Shark Tank on ABC, you should be able to visualize this format. 

Although the originally announced prize pool of $100,000 in cash and in-kind support was impressive, three new sponsors emerged and enabled the awards to swell to almost twice that amount. The new sponsors were Amazon Web Services (AWS), Kickstarter Seed Fund and Sorenson Legacy Foundation. Friday the five finalists competed before a live audience and those watching via streaming around the world. Both those in Salt Lake City and those streaming were able to text their choices. Interestingly, the people's choice and the judges choices were different.


2017 RootsTech Showdown Winners

First Place Judges’ Choice ($90,000 cash, AWS credits, and an investment from Kickstart Seed Fund), Bill Nelson of OldNews USA.

OldNews USA

The easiest way to find your family in historic newspapers - on your phone!

Second Place Judges’ Choice ($44,000 cash and AWS credits), The Qroma tag mobile app for embedding stories into pictures, tagging them by voice commands, and making the data accessible on various platforms.

Third Place Judges’ Choice Award ($26,000 cash and AWS credits), Louis Kessler, Double Match Triangulator, an app to help sort autosomal DNA matches into groups of relatives.

People’s Choice ($25,000 cash and AWS credits), Kindex, an app designed to help users create searchable, shareable archives of family letters and other documents using tags to help users easily locate information.

The distinguished panel of judges were: 

Kenyatta Berry, Co-host of The Genealogy Roadshow; 
Al Doan, Co-founder and CEO of Missouri Star Quilt Company;
Thomas MacEntee, Founder of High Definition Genealogy;
John Richards, Founder and CEO of Startup Ignition; and
Dalton Wright, Partner in Kickstart Seed Fund.

More information about the awards competition can be found in the press release.

Keep in mind that the overall winner may not be the new product that will be the one most useful to you in your research. 

The Innovation Showdown Finalists Are....

Last year a big portion of the $100,000 in cash and in-kind support from the Innovation Showdown at RootsTech 2016 went to TapGenes which has continued to develop its product and outreach. Today the ten semifinalists competing for a similar windfall of support and recognition were winnowed down to the five who will receive final consideration on Friday. By the end of the week the 2017 winner will be announced.

In case you want to look back at those semifinalists now, you can look at my earlier post where the ten are listed with links to where you can find more information.

Judging focused on both the promise of the product as well as the soundness of the business model. Each contestant had two minutes to present the product. Then the panel of five judges had a combined two minutes to ask questions or make comments. If you are familiar with the television show Shark Tank on ABC, you should be able to visualize this format.

These five projects were advanced to Friday's final round. The prize pot is being expanded beyond the announced $100,000. Three new sponsors just signed on. More information about this significant financial and in-kind support will be announced in a day or so.

Double Match Triangulator (DMT)

An autosomal DNA analysis tool for genealogists   From Canada.

Emberall

Capture, organize, store and share the life history of a loved one - from your smartphone in as little as 30 minutes!  caption

Kindex

Accessible, searchable archives for everyone through collaborative record sharing and indexing. 

OldNews USA

The easiest way to find your family in historic newspapers - on your phone!

QromaTag

Add your story to any photo using your iPhone and your voice.
Digital tagging of family photos with metadata and linking to GEDmatch files

As the winner is announced I'll update the list and add more information. If you are among the fortunate twelve thousand or so of my closest genealogical colleagues who have joined me in Salt Lake City for RootsTech, you will have a chance to "kick the tires" and "look under the hoods" of these new products over on Innovation Alley (through the turquoise gateway over the entrance on the left below) in the Exhibit Hall.

If not fortunate enough to be in Salt Lake, I'll update you as the competition unfolds. Keep in mind that the overall winner may not be the new product that will be the one most useful to you in your research. 

Now There Are Ten Innovation Semifinalists

Last year a big portion of the $100,000 in cash and in-kind support from the Innovation Showdown at RootsTech 2016 went to TapGenes which has continued to develop its product and outreach. This year there are still ten semifinalists competing for a similar windfall of support and recognition. That number will be reduced to those to receive final consideration by the middle of next week. By the end of the week the 2017 winner will be announced.

In case you want to take a peek at those semifinalists now, I have listed them below in alphabetical order with links to where you can find more information: 

Champollion 2.0

The scribe for savvy paleographers   

CSI: Crowd Sourced Indexing

Small organizations need an easier way to manage their indexing projects, and this is it. 

Cuzins

Cuzins is a mobile app that shows how you're related to friends & celebrities, and how they're related to each other

Double Match Triangulator (DMT)

An autosomal DNA analysis tool for genealogists   

Emberall

Capture, organize, store and share the life history of a loved one - from your smartphone in as little as 30 minutes!  caption

JoyFLIPS

We combine easy photo scanning, voice storytelling, and AI that brings in relevant historical data from everywhere   

Kindex

Accessible, searchable archives for everyone through collaborative record sharing and indexing. 

OldNews USA

The easiest way to find your family in historic newspapers - on your phone!

QromaTag

Add your story to any photo using your iPhone and your voice. 

RootsFinder

Family history for the whole family 

As the finalists are announced and I've had a chance to examine each product and talk with its developer(s), I'll update the list and add more information. If you are among the fortunate ten thousand or so of my closest genealogical colleagues who will be joining me in Salt Lake City for RootsTech, you will have a chance to "kick the tires" and "look under the hoods" of these new products over on Innovation Alley (through the turquoise gateway over the entrance on the left below) in the Exhibit Hall.

If not I'll try to update you as the competition unfolds. Keep in mind that the overall winner may not be the new product that will be the one most useful to you in your research.