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Welcome!

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And thank you for visiting! My purpose is to help people who may have done a DNA test learn all of the powerful ways they can use it to explore their family history. Disclaimer: I am not a certified Professional Genealogist, simply an experienced and always-learning family researcher with a gift for simplifying complicated concepts to make sense to a casually interested person.

I have spent many years exploring my own history in the British Isles and colonial New England, as well as my wife's Spanish and Polish heritage. I have uncovered fascinating family stories, and had incredible experiences with living relatives. Our family's past has made my present rich indeed, and that is an amazing gift that I'd love to help you unlock.

This blog will feature lots of simple posts on how to make the most of your DNA test in combination with the essential thorough traditional research. We truly live in a "Golden Age" of Genealogy, where our DNA science allows us to relia…

So What Do I KNOW About My Family Now?

Great question, and the answer is "a lot!" But there are limits, and we've discussed many of them in detail in the past few posts. Here are the highlights - some general conclusions and cautions.

There has never been a better time for those interested in their family history to do an autosomal DNA test - the standard offered by all of the popular companies like Ancestry, 23andMe, My Heritage, Family Tree DNA etc. At present more than 20 million people have done so - and that almost certainly includes a lot of people who share some ancestry with you. Add to that the enormous ongoing efforts at digitizing historic records from many countries, and bringing them online along with tools like optical character recognition (OCR) and powerful searching features. It has never before been possible to go so far back into your family's past without leaving your desk!

Autosomal DNA (measured in centimorgans, or cM) can provide conclusive evidence about people to whom we are close…

They Have the Same 5xGreat Grandfather in Their Tree - We're a Match!!!

Perhaps by now you have been exploring Ancestry's "shaky leaves", the little icon that serves notice of a Shared Ancestor Hint in the tree of one of your Matches. And how exciting - they too have a John Smith as a 5x great grandfather (5G), and Ancestry says that you are 6th cousins (6C)! Genealogy and genetics are in agreement - huzzah!

Well, maybe! The amount of the match is pretty small; clicking on the little i in a dark circle on the match page shows that you match at an amount 8 centiMorgans (cM). Since this is above Ancestry's 6 cM threshold for significant match possibilities, they have showed it to you. But….

Each generation doubles in number, and in theory we'd get equal amounts of DNA from each member of that generation:

• 2 parents (50% each)
• 4 grandparents (25%)
• 8 great grandparents (12.5%)
• 16 great-great grandparents 2Gs (6.25%)
• 32 3Gs (3.125%)

....and so on. If we go back in time 10 generations, our theoretical tree includes 1,024 8G grand…

…And What Your Results Don't Mean

In my last post we covered what we can learn from our DNA matches. This post is just as important, for there are many limitations.

We don't inherit the same amounts of DNA from each of our 16 great-great grandparents (2Gs). As we go farther back through successive generations, we find that we don't have any identifiable DNA from many different lines in our family, while DNA from a few branches of our family may still show up 10 to 12 generations distant.

Autosomal DNA has been found to be reliable over 5 to 7 generations. A 3rd cousin (3C) is five generations removed from the Most Recent Common Ancestors (MRCA), a shared set of those 2G grandparents. One in every ten 3Cs don't share ANY common segments with each other. And because siblings get 50% of their DNA from each parent, but not the SAME DNA (other than identical twins), it is quite possible to match some siblings in a family of 3Cs but not every sibling.

Similarly, a 2nd cousin once removed (2C1R) is also five gen…

What Do These DNA Results Mean?....

When your test results arrive - YIPPEE! - you will have a lot of information to sort through. And it can be overwhelming! Relax, take a deep breath, and remind yourself that this will be waiting for you later. Understanding the power of this wealth of family history at your fingertips takes time, as does learning to use it to build your "ancestories."

There are typically three categories on your results page - your settings for your account, an estimate of your ethnic makeup (more about that below), and a long list of DNA Matches. DNA Matches are our genealogy gold mine - these are other users in the company's database who match you, sorted from highest match to low confidence matches. Usually they are grouped into some category of possible relationships, but these are mostly generalized predictive ranges (e.g. 2nd-3rd cousins, 4th-6th cousins, etc.) for all but immediate family.

A quick recap from my last post; these tests look at specific sections of the autosomal DNA …

Testing, Testing - Turn this Thing On!

If you're reading this, you have probably seen those commercials on TV about the home DNA tests - "learn your ethnic origins". As evidenced by AncestryDNA sales recently eclipsing 10 million kits, interest in learning "where do I come from?" has exploded, while technology offers powerful new tools to help answer that question. So what is DNA testing, how does it work, and why should I do it? Great questions!

You have 23 pairs of chromosomes - 22 pairs of autosomes, and the 23rd is a pair of gender (XY) chromosomes. Chromosomes are made up of genes, which in turn are made up of DNA, which is the molecular basis of heredity - the traits we inherit from our parents, and they from theirs, etc.. All of your genes collectively make up your genome. For humans about 99.9% of our DNA is identical, yet this still leaves some 3 million differences between your genome and any other human. (For comparison sake, we appear to share about 96% of DNA with our closest cousin the…

Getting Started - What Do We Know?

This is exciting! We're about to take your family story and build a solid foundation onto which we will add new discoveries. Gather up what you know, get it organized, and let's go.

Whether our plans include use of DNA evidence or not, the first thing to do is to create a tree that includes all that we know. Especially important information includes BMD - birth, marriage and death records including verified dates and locations. The wonderful free resource at FamilySearch.org can be a fantastic asset in getting started with confidence. You can also build your tree there, and even export it to another website or software. (Note: family trees are stored GEDCOM files and have a standard file format just like images, movies and documents - extension .ged).

Why is building a tree so important? It is extremely likely that you have lots of cousins that you've never met, and some of them may be researching a branch of their family that you have in common. You may learn a lot simpl…

A Sharp Eye and an Open Mind

Before we dive deeply into the past, we need a couple of really important tools at all times. It is exciting to start down the trail into the mists of the pasts to explore our family origins. We may have been told some fascinating story about great-grandpa and a harrowing escape during the war, that we have Native American heritage, or an adoptee may have heard that his birth mother lived in a small town outside of Houston but moved to Kansas. It is human nature to seek evidence for a belief or a story that we may have held onto (like the one in my family about being descendants of Robin Hood!).

These are important clues to research! But, they are not facts until they have been proven. If we go into our research seeking to validate a story, it taints how we interpret the evidence - to raise its importance if it supports our belief, or ignore it when it doesn't. This is human nature, and it is called bias. We must take great care not to let preconceptions color our research - par…