Genetic Genealogy

Genetic Genealogy & DNA Tests

I am able to offer assistance with making sense of DNA tests for my clients, and in certain circumstances these can be used to identify and locate relatives (in conjunction with my normal genealogical enquiries).  This is now termed ‘Genetic Genealogy’.

If you have a specific question you would like resolved, contact me and I will be pleased to discuss with you what can be done with DNA test results and what they can do to get answers for you.

There is much information available about DNA testing, and much advertising by the major DNA testing companies encouraging everyone to get a test.  To help out I have added explanations below to common questions about DNA testing, which may help in your decision making, and added some links which may be of assistance, for which I have used some links to ISOGG as these are source of non-technical explanations aimed at the layman.

As of the end of 2020, about 30+ million consumer tests have been carried out by the testing companies (excluding the tests carried out for investigative purposes), worldwide.  A great increase on just 2-3 years ago, but only a very small number in terms of worldwide population, a big percentage of these test are from North America. Ancestry have said they have tested about 18 million (as of February 2021)

I am not affiliated with any of the testing companies in any way, and I cannot recommend any one of them to you, or a specific DNA test until you speak to me about the questions you want a DNA test to resolve.

I cannot advise about DNA testing for health issues, this is best done in conjunction with your medical advisors.

  1. The Test Kit

There are 3 different types of DNA test that can be taken, all of which involve being sent a ‘test kit’, consisting of a cheek swap or a spit tube, to gather your saliva for the test.  This is sent to you by the testing company you have selected.  When you have done the test, the kit is then mailed back to the testing company.

  1. The DNA test

The testing is done at the testing company labs, which are currently in the USA, and the sample of your saliva (the ‘dna test sample’) is stored there after receipt and after initial testing has been done.  The results of your test are sent to you by an emailed notification to login to the testing company website to see the results and any DNA matches.

The DNA test sample is kept for a period of time, or can be destroyed on request, all of the companies have strict rules on access and identification of samples.

  1. The testing companies

The main consumer testing companies are:  Ancestry, Family Tree DNA, My Heritage, 23andMe and LivingDNA, with a number of smaller companies also offering tests.

  1. The different DNA Tests

Autosomal DNA – often branded as ‘Family Finder’, technically referred to as ‘atDNA’, can be taken by everyone, and will give results for matches up to 6-7 generations back.  All of the testing companies offer this test.

Y-DNA – this is a test for men only as it tests the male only Y chromosome (females have two X Chromosomes, males have a Y and one X Chromosome), and can be taken in various versions, although the Y-37 test is the usually recommended start test for any genealogical or male family origin research.  Family Tree DNA is the only company that currently offers these tests. 

Mitochondrial DNA (mtDNA) – a test for the female line inheritance, as this type of DNA is passed down the female line from mother to children, so a man has his mother’s mitochondrial dna, but his children have the mitochondrial dna of their mother, his mitochondrial dna is inherited from his maternal grandmother (and hers from her mother), via his mother.  This test will get matches related on the direct maternal line of the family tree, or females descended from the direct maternal line.  

  1. Test Costs and discounts

The testing companies offer the tests at about £99 for a Family Finder test, or YDNA mtDNA test for the basic markers, although the cost is often discounted from time to time, usually around holidays or festivals (Christmas, Thanksgiving, Valentines Day …).  The more detailed YDNA tests can cost considerably more.  The cost of a test can be shared within a family or group of relatives, easily done with FamilyTreeDNA’s ‘Donation’ facility which can be used in conjunction with a ‘surname project’ to add funds to the project general funds.

  1. Getting the Results

Testing a kit does taken some time, usually about 4-6 weeks.

  1. Matches

Matches are other people who have been tested, usually with your selected testing company, who share a sequence of DNA with you (a ‘segment’) which is of a certain size to be a significant match (usually around at least 7cMs).  The closer the relative is to you the greater the size and number of the matching segments, up to a full match with you (if you have an identical twin) or matching half of your DNA if the match is your parent (usually expressed as about 3485cMs). See the relationship table at & the explanation of cMs (CentiMorgans) at 

  1. What is a Surname Project?

This is a collection of y-dna results collected together so they can be compared with one another and common results identified.  This is for men only, but families can participate if they get a male of the family tested.  These are free to join (plus the cost of the Y DNA test) and are run for any particular surnames by Family Tree DNA, see my surname project on the English Suffolk surname ‘Runacres’.

  1. Ethnicity Results

DNA test can also predict your ethnicity, predicting the regions or countries of your ancestors, and many of the testing companies will provide a map showing the regions and percentages for your ancestors’ origins.  This is often at the forefront of the advertising, and is often a major attraction for many who take the tests.  However, this is only a prediction, and its accuracy may not be very precise.

Ethnicity results are a result of comparing your results with those of a reference population already tested (a static series of test results set periodically by each company which is revised periodically), so the accuracy will improve as more and more people get tested, and the ethnicity results will change over time – so this year’s results will differ from next year’s, without any change in your test results!

A better ethnicity estimate can be found via a Y Chromosome or  mtDNA test which will have a prediction of the haplogroup of your distant ancestry, and can show a predicted migration path for that group of people – ‘group’ being ancestors at least several hundreds of years ago.  A little confusingly, your predicted haplogroup is different for your paternal and maternal relations, as it tracks different ancestorial paths.

Another way to predict ethnicity is by tracking the ancestors of DNA matches and their surnames and places/countries of birth.

  1. Can my results be used by law enforcement?

You may have heard about consumer DNA tests being used to solve some missing person and violent crimes, and currently (from March 2020) most of the testing companies either do not allow law enforcement to use the testing data (the consumer test kit results) or allow use if the person tested has opted in (agreed) to use by law enforcement.  If this is a concern for you, then you should check the terms and conditions when you apply for a test, and when you transfer the results to another site (if you choose to do this).

  1. Social Consequences (a Warning)

It is said ‘DNA does not lie’, but interpretation may be mistaken.  If your immediate family inheritance is uncertain you should seek advice or counselling from someone who has experience of and can interpret results for you, before you take a test or see the results. Tests will reveal unexpected relationships if there has been doubt about parentage, and matches can be shown to relations who you may not know or be aware of.  Test results can and will show matches to whom you do not have any connection or relationship – and are just co-incidental matches, particularly with cousin matches distantly related.

These results then will affect your current family, and may have a potentially serious consequences for everyone if parentage has been concealed or where step-families are involved.

  1. Contacting Matches

If you want to contact a DNA match, you can do so via the testing company, or by a submitted email address, but please do so treating the match as you would with contact with a stranger or business; don’t ask for too much all at once, and be honest about your reasons for the contact.  Don’t expect a quick response, as many of the messages passed rely on how often that person connects to your testing company’s systems, or if by email, give them time to consider your request.

Take advice on testing, and be aware of what you can achieve and cannot achieve, so be prepared.

Next Steps

For anyone with unknown parentage or unknown ancestors, or adoption, I am able to advise and assist to identify relatives or parents via DNA and genealogical research – they go together! Fill in my contact form giving me a contact number or email and a brief description of what you need to discover and I will get back to you.

Learn more with a custom webinar with me about DNA Tests for genealogy, where you can learn about your own matches and how to explore them from me.  See my webinar page.

There are many DNA matching tools available for testees to use, and many of the companies allow their kits to be downloaded and then uploaded to other companies or DNA matching websites. One such site is

If you wish to explore further, I recommend you start with the ISOGG website (which is run by a group of genetic genealogists).