DNA Testing Strategy for Your Family Tree
Learn how to strategically plan DNA tests to get maximum genealogical value from your family tree research.
Why DNA testing order matters
Not all DNA tests are equally valuable for genealogy. The oldest generation carries the most unique DNA that's being lost each year. A DNA sample from a 90-year-old great-aunt is genealogically more valuable than testing yourself, because she carries DNA segments from ancestors that may not have been passed down to you.
Strategic testing means identifying which living relatives carry the most unique ancestral DNA and prioritising them before it's too late.
GEDminer's DNA Planner
The DNA Testing Planner analyses your GEDCOM file to identify:
- Patrilineal lines: Male-line ancestors traced through Y-DNA inheritance
- Unique surnames: Distinct family lines that could benefit from testing
- Testable individuals: People likely still living based on birth dates
- At-risk individuals: Elderly relatives whose DNA should be preserved soon
The planner helps you see which branches of your tree have the most to gain from DNA testing.
Which tests for which questions
Different DNA tests answer different questions:
- Autosomal DNA: Best for finding cousins within 5-6 generations. Test as many relatives as possible.
- Y-DNA: Traces the direct male line. Test the oldest male in each surname line.
- Mitochondrial DNA: Traces the direct maternal line. Less useful for most genealogy but can confirm maternal ancestry.
For most genealogists, autosomal DNA provides the best value. Y-DNA is essential for surname studies.
Prioritising who to test
Follow this priority order:
- Oldest generation first: Great-aunts, great-uncles, elderly cousins
- Unique line representatives: The only living descendant of a particular ancestor
- Brick wall branches: Relatives connected to your most challenging research problems
- Diverse branches: Test across different family lines, not just one
- Yourself: Test yourself to have a baseline for comparison
Even if an elderly relative has passed, consider testing their children - they carry 50% of the parent's DNA.
Using results with your tree
Once you have DNA results:
- Compare across platforms: Several services accept raw DNA uploads, expanding your match pool
- Sort matches by shared cM: Higher shared DNA means closer relationships
- Use GEDminer's Kinship Explorer: Calculate expected shared DNA between any two people in your tree to verify matches
- Build clusters: Group DNA matches by which ancestor they connect through
- Document everything: Add DNA evidence to your source citations in your genealogy software