What to do after you’ve taken a DNA test

Getting ready for your results & learning more about DNA

Once you decide on a DNA test use the time waiting for your results wisely – get your tree up to date and check for accuracy. I know I’ve found mistakes on mine so it is a good idea to give it a spring clean and check it from roots to bud!

Have fun! Any mistakes you may make when experimenting with your ancestry DNA test results can be corrected and be sure of the fact that the companies continue to add new features and developments to aid you with your DNA journey.

The guide and glossary are by Karen Evans, with glossary input from Donna Rutherford and John Cleary.

Watch videos and read up on using your test company

Get the best from your results.

MyHeritage have a Knowledge Base for example which has compiled short videos on many aspects of its DNA test, for instance.

To learn more about each of the main DNA family history websites, explore our guides to the testing companies:

Ancestry

FamilyTreeDNA

MyHeritage

LivingDNA

23andMe

What tools do genetic genealogy testing companies provide?

DNA genealogy testing companies provide tools such as details of your shared matches, tools to help you put your DNA matches into groups that share DNA with one another, family trees of you DNA matches and family tree building tools. Each DNA testing website provides a different selection of tools. AncestryDNA and MyHeritage lead the way with tools and this shows in my discoveries.

Tools really are a game changer in helping you discover how you and a match may be related. I have occasionally found a connection using a match’s name only, but this is much more difficult and not to be expected at all.

As I say, AncestryDNA and MyHeritage lead the way with tools and this shows in my discoveries.

Of the 161 4th cousins or closer I have found on my maternal line, the majority are from AncestryDNA, 18 from MyHeritage, 6 from 23andMe and 4 from FamilyTreeDNA.
So here are a list of some of the tools that companies offer to help you with your matches.

Do you need to pay extra at DNA genealogy testing companies?

The access you get to the DNA testing companies' websites varies. Very often, in addition to having purchased a DNA genealogy test, you will also need to buy some sort of paid membership or pay some sort of add-on fees in order to access more of the tools for the DNA testing company you are using.

When the sites are fully operational the DNA tools and resources available include such things as: a match list; a chromosome browser; surnames of interest; and relatives in common (or a shared matches facility which allows you to group matches to find a common ancestor).

Only FamilyTreeDNA and 23andMe allow access to their whole site without needing to pay for upgrades/add-ons.

LivingDNA does not require a subscription to access its match list and tools but offers paid add-ons comparing your DNA to groups such as Vikings, for instance.

AncestryDNA is a little more complicated. You need a paid membership to gain access to your shared match list and most tools. This can be a family history membership to Ancestry, or Ancestry also offers an AncestryDNA Plus membership. A regular Ancestry family history membership will give access to everything without the need for the AncestryDNA Plus membership. Ancestry Pro Tools subscription too (£7.99 per month, paid monthly, over and above any other Ancestry membership you may have) provides access to additional tools - most usefully and importantly 'enhanced shared matches'.

So that leaves MyHeritage. I love their DNA site but you cannot access many of its features without a subscription. This includes the shared matches facility or your match’s tree. Although you can still use your match list, it makes it difficult to discover their connection.

Learn about grouping & match labelling to colour-code your ancestry DNA matches

Colour-coding your DNA matches enables you to group matches together into possible ancestral lines. It goes hand in hand with shared matches. The ‘coloured dots’ are currently available on AncestryDNA, MyHeritage and LivingDNA.

Below is an example of some of the groups that Karen has created for her Mom on AncestryDNA.

How can a chromosome browser help me with DNA?

A chromosome browser is a more advanced DNA genealogy tool which shows where you and your match share the segments of DNA on one or more of the pairs of chromosomes. It can be useful for identifying matches who share the same ancestors (using triangulation) and is used to build up your personal chromosome discoveries.

MyHeritage and FamilyTreeDNA have chromosome browsers at the moment. 23andMe have have a version of their own former chromosome browser, which is known as the Advanced DNA Comparison tool.

DNA glossary for family historians

DNA has a language of its own, one you may be unfamiliar with, but it’s worth getting to grips with it to help you make use of genetics in your genealogy.  I have included only those words that crop up really frequently when talking about DNA and family history. Some are general scientific terms and others are phrases that have evolved, specific to the genealogy community. Below they are explained in fairly basic terms but there are also included links to help you delve deeper. [This glossary was published in the January 2026 issue of Family Tree and compiled by Karen Evans with input from John Cleary and Donna Rutherford. We are grateful for all their assistance.]

Autosomal DNA

‘Autosomes are the 22 pairs of non-sex chromosomes found in both males and females,’ writes genetic genealogist Donna Rutherford. ‘The 23rd pair are the sex chromosomes (X and Y). Most consumer DNA tests (like AncestryDNA, 23andMe, MyHeritage, etc.) are based on autosomal DNA, which can identify relatives from both sides of your family, going back about 5–6 generations.’

Biogeographical ancestry

Biogeographical ancestry (BGA) (also known as Origins, My Origins, Ancestry, Ancestry composition, and formerly referred to as an ‘ethnicity estimate’). Biogeographical ancestry gives a breakdown of where your ancestry comes from geographically. Each company compares your DNA to a reference panel made up of people whose ancestry indicates a long history in a particular region. They see which population in the reference panel each segment of your DNA looks most similar to and add up the results to get percentages.

Because each company has a unique reference panel and analyses your DNA slightly differently you will find that your biogeographical ancestry will vary according to which company you have tested with. Biogeographical ancestry is generally accurate at the continental level but the fact that the same test can show different results depending on the platform indicates how approximate they are.

DNA companies amend their reference panels periodically and update the way they analyse DNA to improve precision. You may see additional biogeographical regions, regions that change geographically or ones that disappear altogether.

This means that your ethnicity estimate will change over time with each company, even though your DNA doesn’t change. Ancestry also show a range within each ancestral region.

CentiMorgan (cM)

‘The amount of shared DNA you share with a genetic match is expressed in centiMorgans,’ writes John Cleary.

Donna Rutherford expands: ‘It’s a measure of how likely recombination is to occur between two points on a chromosome. In practical terms, the more shared centiMorgans you share with someone, the more closely related you are likely to be.’

Chromosome

Chromosomes are found inside the nucleus of a cell. Inside each chromosome is DNA. Humans typically have 23 pairs of chromosomes, that is 22 pairs of autosomes and one pair of sex chromosomes. Each pair contains one chromosome from the mother and one from the father.

Chromosome browser

This is a tool displaying which segments of a chromosome you and a DNA match share. MyHeritage, LivingDNA and FamilyTreeDNA have chromosome browsers.

Clusters

Clusters ‘are groups of DNA matches who are also related to each other, writes Donna Rutherford. ‘If several of your matches share DNA with one another, and with you, they are likely connected through the same common ancestor or ancestral couple.

‘Clustering helps you figure out which branch of your family tree a DNA match belongs to. Most testing companies offer tools to help identify shared matches and group them into clusters to support your research. Some companies (like Ancestry and My Heritage) offer visual cluster tools, often called “auto-clusters” which display the groups of related matches.’

• Find out more on the MyHeritage education hub

Endogamy

Endogamy is the practice of marriage within the same cultural or geographic group over many generations, for example Ashkenazi Jews, Polynesians or Amish populations. ‘This impacts the genetics of descent,’ writes John Cleary.

From a DNA test results perspective, ‘This causes people to appear more closely related than they really are,’ explains Donna Rutherford, ‘because they may share DNA from multiple common ancestors.’

Learn more from the DNA Geek about endogamy.

Ethnicity estimate

See ‘biogeographical ancestry’.

GEDmatch

GEDmatch is a free site where you can upload your autosomal DNA test, looking for matches from other testing sites.

Gene

A gene is a precise section of DNA that has the instructions to influence some trait or aspect which makes you, you.

• Learn more about genes in the Ancestry learning hub

Haplogroup

‘A Haplogroup represents a deep ancestral line and is based on specific DNA mutations passed down through either the direct paternal line (Y-DNA) or the direct maternal line (mtDNA),’ writes Donna Rutherford.

John Cleary expands: ‘Haplogroups are identified by possession of particular shared markers – SNPs [pronounced ‘snips’ – Single Nucleotide Polymorphisms]. A haplogroup is a group of testers who share a SNP through descent from a common ancestor. It’s the SNPs that are given names, and these are used to identify haplogroups.’

John Cleary continues: ‘Biological males can be assigned to two haplogroups: Y-DNA and mtDNA; biological females can only be allocated to an mtDNA haplogroup.’

Donna Rutherford continues: ‘Haplogroups are used to trace ancient migration patterns and deep ancestry, they don’t identify recent relatives.’

• You can learn more about haplogroups at this 23andMe blog post.

Identical by descent

Identical by descent (IBD) An identical segment of DNA between two or more matches inherited from a common ancestor is known as IBD.

There may be reasons why you share DNA with a match that is not IBD and that is covered in detail here: dna-explained.com/2016/03/10/concepts-identical-bydescent-state-population-and-chance/

Matrilineal

Matrilineal is the direct maternal line following your mother’s mother’s mother’s line.

Mitochondrial DNA (mtDNA) Genetic material inside the mitochondria, which are the ‘powerhouses’ of a cell. Both sexes inherit Mitochondrial DNA from their mother but only females can pass this genetic material to their children. Because mtDNA changes (mutates) slowly, it’s useful for tracing direct maternal ancestry over a vast time period. Only FamilyTreeDNA offers an mtDNA test with matching database.

• You may find this video from by Martin McDowell on YouTube, about mitochondrial DNA helpful.

MPE or misattributed-parentage event

MPE or misattributed-parentage event, also known as NPE – ‘not parent expected’ or ‘non-paternity event’.

Donna Rutherford sums it up as: ‘An MPE/NPE is when a person’s biological parent is not who they expected, often due to adoption, donor conception, infidelity or undisclosed family events.’

Whichever acronym you prefer, they all basically mean the same thing – someone on your tree does not have the biological parent (or parents) you thought they had.

Many people think an MPE is a child where the attributed father turns out not to be the true one, due to a ‘liaison’ outside of the known relationship. But there are many scenarios where the presumed parents might not be the biological ones.

• An adoption to unrelated family took place that was either secret or has been forgotten over time.
• A child was brought up by a stepfather but, because of time or surname change, you believe he is the biological father.
• A child was brought up by the real parents’ family eg a married sister bringing up her unmarried sister’s child or grandparents taking on their son’s illegitimate child
• A donor situation of sperm (and/or more recently of an egg)
• The tree created is incorrect because you have followed the ‘wrong’ John and Mary Smith.

Most Recent Common Ancestor (MRCA)

Most Recent Common Ancestor (MRCA) is the closest ancestor, or ancestral couple, you and a match share.

Patrilineal

Patrilineal is the direct paternal line following your father’s father’s father’s branch.

Pedigree collapse

Pedigree collapse happens when a couple who share a common ancestor or ancestral couple reproduce. The resultant child will have fewer unique ancestors than expected.

Quick and Dirty Tree

A Quick and Dirty Tree is sometimes known as a ‘research tree’, this is created to find how you may be related to a match. It is done with speed (Quick) and using information which may or may not be accurate (Dirty). These trees should always be private and unsearchable to others so any mistakes are not perpetuated.

Recombination

Recombination is the process where segments of DNA on pairs of chromosomes are exchanged and rejoined when an egg or sperm is made to create new combinations of genetic material. Recombination is random so each egg or sperm will carry its own unique combination of the parent’s DNA.

Relationship calculator

Testing companies use the amount of DNA you share with a match to predict the relationship you share. These are always estimated as no test can categorically know how you are related. Some companies give all the possible relationships that you and a match share and how probable they are.

Segment

A segment is a ‘piece’ of DNA from a chromosome. ‘A shared segment is a stretch of identical DNA,’ explains Donna Rutherford. ‘Be aware that segments under about 7-10cM may be false positives or not IBD.’

The longer the unbroken segment the more closely you tend to be related to your match. Many testing companies tell you how many segments you share with your match.

Timber

Timber is an algorithm created by AncestryDNA which ‘downweights’ segments of DNA that it believes may not be shared because of a common ancestor.

• Find out more about Timber in this Ancestry article.

Whole Genome Sequencing (WGS)

Whole Genome Sequencing examines the entire genetic code of an individual. In autosomal DNA testing typically 700,000 SNPs (pronounced ‘snips’ – Single Nucleotide Polymorphisms) are analysed, but in WGS the entire run of 3 billion base pairs are looked at.

Y-DNA

The Y sex chromosome is only found in biological males. The Y chromosome is passed directly to a biological male from his father, who inherited it from his biological father, and so on. This is known as the patrilineal line.

• See more about Y-DNA at Your DNA Guide.

Y-DNA testing

Y-DNA testing can be used by people with a Y chromosome to research their patrilineal ancestry. Because the Y chromosome is passed down with very few changes (mutations) over many generations it can be used to trace your biological father’s paternal line a long way back in time – thousands or even tens of thousands of years. FamilyTreeDNA is the only company to offer Y-DNA testing with a matching database.

• Find out more about Y-DNA testing on  YouTube, in John Cleary's presentation.

TAKE YOUR LEARNING FURTHER...

Included in this glossary are only the most common words used in genetic genealogy here, and they are explained here at a basic level.

As your interest and confidence increase you are bound to come across many more, and you might find these other glossaries useful:

• The Ancestry Glossary

• The International Society of Genetic Genealogy Glossary

• The FamilyTreeDNA Glossary