DNA & A Question of Paternity: Part 7 – Bringing the evidence together

For the past several weeks, I’ve been describing a project for which I used various types of analysis to attempt to clarify the uncertain paternal ancestry of someone I’m calling “Bob” (all names in these posts have been changed for privacy). In this post, I’ll summarize the results of the analyses in the previous posts...

DNA & A Question of Paternity: Part 6 – Statistically testing hypothetical relationships

To predict the most likely locations for someone in a family tree (relative to DNA matches with a common ancestor), I've used the What Are The Odds? Tool to thoroughly test hypothetical trees and determine more or less likely relationships. As a complement to documentary research of a family, this has helped me narrow down paternal candidates for someone with uncertain genetic ancestry.

DNA & A Question of Paternity: Part 5 – Bringing together Autosomal & Y-DNA Results

Last week, I described using autosomal DNA matches, their relationships to each other, and their trees to start to construct a new family tree for someone (“Bob”) with uncertain paternity. The most recent common ancestor (MRCA) for Bob and some of these matches appears to be a woman born about 115 years before Bob, who...

DNA & A Question of Paternity: Part 4 – Building a New Family Tree

Over the past few weeks, I’ve been describing a problem I’ve been working on: using DNA to learn about the ancestry of someone (“Bob”) who was uncertain of the identity of his biological father. After examining what the paper records suggested for Bob’s maternal and paternal ancestors, I looked at Bob’s top DNA matches. Some...

DNA & A Question of Paternity: Part 3 – Identifying Autosomal Matches

After putting together Bob’s maternal and paternal family tree (according to paper records), I took a closer look at his autosomal DNA matches to see how they compared.

DNA & A Question of Paternity: Part 2 – Starting with what we knew

Last week, I introduced a project I have been working on to try to use DNA to learn about the paternal ancestry of someone who wasn’t sure of their father’s identity. As I mentioned before, I won’t use any real names here; I’ll call the person testing “Bob.” We ordered tests, sent in saliva, waited,...

DNA & A Question of Paternity: Part 1 – Introduction

Almost two years ago, I was talking with an acquaintance who had been uncertain of the identity of his biological father for much of his life. I suggested the idea of DNA testing to him; I would help him, and we would see what we could learn about his genetic ancestry. He was open to...

Questioning the Question

Thinking carefully about a research question before diving in can help to a) highlight what I already know and b) define what, precisely, I want to answer with my research.

Ethnicity Estimate Comparison Pie Charts…or DNA Doughnuts

Yesterday, in a guest post on the DNA Geek blog, Erik Schaefer used Excel pie charts as a fun way to visually compare different ethnicity estimates, with examples comparing paper records to DNA testing. I gave it a try with my own data. I was able to use Erik’s instructions pretty well, though on my...

Chromosome Mapping – A First Pass

I’ve seen some of the wonderful chromosome mapping images that others have generated, but I hadn’t yet gotten around to mapping any of my own DNA. Letting the perfect being the enemy of the good, I figured I hadn’t done enough analysis to be ready to map my own data yet. This week, I gave it a try.