Genealogical DNA Analysis Tool

Utilizing Autosomal DNA to Research Family Trees

What is Genealogical DNA analysis?

Genealogical DNA analysis is a method that can be used to trace a person's ancestry and family history using DNA samples. DNA, or deoxyribonucleic acid, is the genetic material that is found in the cells of all living organisms and carries the instructions for the development and function of the organism.

Genealogical DNA analysis involves analyzing specific regions of a person's DNA, known as markers, to identify patterns and similarities with other individuals. These patterns can provide information about a person's ancestry and family history.  It can provide information about a person's heritage and help them connect with distant relatives. However, it is important to note that genealogical DNA analysis is not a perfect science, and the results may not be 100% accurate. It is also important to be aware of the potential ethical and privacy implications of DNA testing.


The Genealogical DNA Analysis Tool (GDAT) is an app developed by Becky Mason Walker (Beckins LLC) that utilizes autosomal DNA to aid in the research of family trees.   GDAT is specifically designed to analyze DNA data from genetic genealogy tests and help users identify their biological family members and ancestry.

GDAT provides several features for analyzing and visualizing DNA data, including triangulation, segment analysis, chromosome mapping, and ancestry estimation. It also offers various tools for comparing and filtering DNA matches, including surname searches, geographic searches, and pedigree analysis.

GDAT is available for download as a desktop application for Windows, Mac, and Linux operating systems.

History and Purpose

GDAT was released by Beckins LLC in January 2020 to replace its predecessors, Genome Mate and Genome Mate Pro.

The purpose of GDAT is to collect in one place the data from genetic genealogy tests and provide the tools to conduct family tree research using DNA. It is specifically designed to store data locally in an encrypted database on the user's desktop computer, not on an internet server or the cloud. It provides a generic import process that allows users to import data obtained from the testing companies of their choice.

Types of Data Collected

Analysis Fundamentals

Core to the Genealogical DNA Analysis Tool functionality is identifying the Most Recent Common Ancestor (MRCA) between the profile person and associated relatives by reviewing relative ahnentafels and assigning a group name to each DNA segment. Group names are derived from the standard surnames of the MRCA's parents (i.e., Mason-Miller) and automatically assigned when the Profile person's ahnentafel is loaded.

Given the vagaries of surname spelling, a standard surname table is populated from the Profile's ahnentafel and can be modified or expanded by the user. All ahnentafels are assigned a standard surname from this table when loaded, providing the ability to assist in the identity of a relative's MRCA.

Once a known MRCA is identified, unknown relatives can be researched utilizing GDAT's built-in triangulation and mutually in-common-with (ICW) functions. Triangulation involves identifying 3 individuals descended from 3 different siblings of the same ancestral couple on the same DNA segment. One of these individuals being the Profile person.

For example, on chromosome 12 from base pair 24.5 to 76.2, a triangulation between Becky the profile person, DNA relative Jack and DNA relative Jill means there are DNA segments identified between Becky and Jack, Becky and Jill as well as Jack and Jill. This means Becky, Jack and Jill descend from the same ancestor.

Triangulations assist in identifying what branch of the Profile's family tree that all three are all related and can be used to identify previously unknown ancestors when shared ancestors are found in the DNA relative's ahnentafels. Mutually ICW is used when triangulation data is not available and is less reliable as it says that all three people are related but not necessarily on the same DNA segment.

Analysis Tools

The Genealogical DNA Analysis Tool app provides several tools that assist in finding Most Recent Common Ancestors (MRCA) of DNA relatives whose MRCA is unknown.


The Genealogical DNA Analysis Tool app features include:

Quick Links

If a menu is not displayed on the left hand side of the screen, clicking on the three horizontal lines in the top left hand corner will show the full menu.