This post is the second in a series developed to support the Genealogical DNA Analysis Tool (GDAT) User Group at the Society of Australian Genealogists (SAG). It does not replace the extensive user guide and help video tutorials already developed by the GDAT team. Members of the User Group should always consult those resources first.
You can access Part 1 by clicking on the link below, or the user guide for more specific information.
DNA Research Methodology
To get the most out of your DNA results you need to apply the DNA Research Methodology, first published in 2021. GDAT caters for working on both sides of the DNA Framework:
* Broadly - via Total cMs (F8) and tree triangulation; or
* Specifically - by chromosome (F7) using both segment triangulation and tree triangulation. It is at the segment level that GDAT provides the most benefit.
Identifying shared ancestors via tree triangulation requires work. You need to build out your own tree to at least 5th great grandparents, where possible. In working with your DNA matches you will often need to also need to build out their trees and analyse the results to identify the shared ancestors.
Always work on your largest matches first. When using the broad approach we focus on shared matches and clusters to identify the common ancestor. Past 2nd great grandparents we utilise the specific approach using chromosome analysis to identify triangulated segments and groups. Whether you are working with shared match clusters or triangulated groups, the methodology is the same to identify the common ancestor through tree triangulation.
When there are no privacy concerns (particularly people who were born over 100 years ago), don't hide all that extra research in private trees - add them to a 'free' one world tree such as Wikitree to assist other researchers.
Relevant Workspaces and Tools
As you work with the genetic tools you will be predominately working in the following three GDAT workspaces. When you first start using GDAT it can be difficult to navigate the site and to be clear about the different perspectives you need to apply when working in each of these areas.
- Relative - views relevant to your DNA matches;
- Profile - views relevant to people whose DNA you are monitoring;
- MRCA - tools to assist your research.
- Overlapping segments;
- In common with (ICW) on the same segment;
- Triangulation - what it is and when it shows data on GDAT.
- F8 - Relative List: This page is best for viewing all matches by total cMs. It also has many useful search and filtering functions;
- F1 - Relative Page: This is where all the data about your DNA match (Relative) is stored. It has an extensive notes field and quick links to DNA match pages, pedigrees and email;
- F7 - Chromosome Browser: There is a separate chromosome page for each of the 23 chromosomes for every profile. This is where you identify matches who may belong to the same shared ancestor group. It can be sorted and filtered in different ways;
- F4 - DNA Comparison Page: if you have loaded sufficient data, this is the engine room for your analysis. You can often make decisions about matches without the need to go back and forth to the DNA testing site, saving research time.
To get help:
* Make sure you first consult the extensive GDAT User Guide;
* Join the Facebook Group for GDAT and search the site to see if the question has been asked before. If not, ask the question there;
* SAG members can join the 'private' SAG GDAT User Group on Facebook for general collaboration between members.
* Back up regularly (under File);
* Use the available Help resources (under Help);
* If imports or views aren't behaving as you would expect, you probably need to adjust some of the defaults (under Preferences)
* Keep notes, one of the great features of GDAT is being able to easily pick up where you left off last time!
Finally....
