The test that can tell you about your ethnic makeup is called an autosomal DNA analysis – also known as an ethnicity test – and it can reveal the population groups from this thousand year period who have contributed to your ethnic mix. It’s called an autosomal analysis because it looks at your autosomes; these are our non-sex chromosomes and they make up 22 of the 23 pairs of chromosomes that we inherit from our parents.
The little changes are where “mutations” occur over generations – these aren’t necessarily bad, it just means that the gene has been copied slightly differently as it passed from father to son. Because its possible to predict how often mutations are likely to occur, comparing the Y-DNA from distant male cousins with a common ancestor (and seeing how many differences there are in a standardised set of markers tested) allows a rough estimate of when that common ancestor might have lived. A very close match between two men who share a common surname (only one or two differences) makes it very likely they are related, and a bigger number of differences makes it either less likely they are related, or that the most recent common ancestor is very many generations back.
Most ancestry DNA kits cost about $100. AncestryDNA, 23andMe’s Ancestry test and National Geographic’s Geno 2.0 test all fall nicely into that price point. If you’re looking for a bargain, we recommend waiting to buy until your preferred test is on sale, as they’re often available well below their usual price. To get the most for your money, buy an Ancestry or 23andMe kit on sale then upload your raw data to MyHeritage DNA’s database, which is free. 
DNA profiling isn’t exclusive to human DNA. Animals also have genetic markers in their DNA which can be used to build up a profile for DNA identification or determining parentage. The most common animals that this is used for are dogs. Similarly to human DNA profiling, dog DNA profiling uses 10-20 markers in order to build up a profile that can be used to identify your dog if it is ever lost or there is some kind of ownership dispute. Companies that offer this service will often include the profile in the form of a certificate, with details about your dog along with its DNA profile. It should also be said that these companies tend to store your dog’s profile in their database, so you that you can check back with them if you ever need to.
Companies like Embark, Wisdom Panel and many others offer genetic health risk screenings, trait analyses and breed percentage information for dogs. These canine ancestry tests allow you to confidently state that your mutt is part Irish wolf hound and give you key information about your pet’s heritage for insights into potential health issues. For example, if you find out one of your rescue dog’s parents was likely a purebred boxer, you could speak with your vet about breed-specific needs. Basepaws DNA CatKit promises information about your cat’s breed and traits with just a hair sample, though it offers swab kits for hairless cats. The kit also tells you how closely related your kitty is to wild cats like lions, tigers and ocelots.
Men have an X and a Y (chromosome) that are paired together. Women don’t have the Y, they just have two X’s. A child’s genes come from a mix up and recombining of the two parents. So a girl child will still end up with two X’s but some bits of them will come from the father’s X and some from the mother’s. A boy child on the other hand may have some bits of X from both mother and father, but his Y will have just come purely from his father – virtually unchanged. That makes Y-DNA such an exciting possibility for genealogy where you want to follow the paternal (surname) line. You could expect that Y-DNA will therefore pass virtually unchanged from father to son through the generations, meaning that the Y-DNA of a man’s g-g-g-g-grandfather will look very much like that of his own Y-DNA – with some little changes.

Most companies will use algorithms to compare the genetic variants uniquely associated to a reference population with those identified in the person being tested. This can help them exclude unlikely population groups from your ethnic mix, and ensure that the ethnic groups you’re shown to be composed of are more accurately reported. Although most companies will share the reference populations they use with their customers, they rarely provide information on the algorithms they’ve developed.
This is very interesting…thanks for sharing—regarding you husband’s results– the Somali 1% might not be so crazy at all—look at the map– horn of east Africa to Yemen area (had a large Jewish population long ago)…to Palestine-Israel…to Europe in the centuries long diaspora..actually your comments made me more inclined to try this newer company. I am grateful to you.
DNA profiling can also be useful for those who suspect there may be inheritance disputes over their estate once they have passed away. It provides a record that can be referred to long after someone’s death, even when all physical traces of DNA have gone. Therefore, if there is an unexpected claim for inheritance from an alleged relative, your DNA profile can be compared to that of the claimant to prove or disprove a biological relationship and the inheritance rights.
The BBC has updated its cookie policy. We use cookies to ensure that we give you the best experience on our website. This includes cookies from third party social media websites if you visit a page which contains embedded content from social media. Such third party cookies may track your use of the BBC website. We and our partners also use cookies to ensure we show you advertising that is relevant to you. If you continue without changing your settings, we'll assume that you are happy to receive all cookies on the BBC website. However, you can change your cookie settings at any time.

Consult a doctor on any health data: Cancer. Leukemia. Heart disease. Alzheimer's. There are a lot of scary afflictions out there, and your DNA testing may well indicate which ones to which you are genetically predispositioned. But the data from DNA testing exists in isolation. You should consult your doctor to explore the data from any of these tests. They'll help you determine how to implement any lifestyle changes or followup testing as a result, if it's worth doing so.

Each ancestry DNA service has its own sample database and reference panel made of the DNA samples collected from their users and information collected from sources like the 1000 Genomes Project. The database consists of all this information collectively. A reference panel is made of certain curated samples with known family history and roots in a specific place. The services use insights gleaned from the reference panel to give you geographical ancestry results. In theory, a larger database leads to more information available to create a good reference panel, which then leads to better results for customers.  
And that’s where it starts getting interesting, because then we can start comparing that genetic signature to the results from other men who share the same surname but don’t appear on our family tree. If the matches are close, then we can start thinking “is there a common ancestor for these families another generation or two back? Are the families linked in some way?”. Depending on what we already know about either family group, it can help target the paper research to get those families linked, or take us back another generation or two.
Below we have included both a quick comparison chart that looks at each DNA testing option side by side and a detailed breakdown of each section in that chart. We’ve covered Family Tree DNA, MyHeritage DNA, AncestryDNA and 23andMe in our comparison because these four companies are the main trusted providers of genetic genealogy tests in the current market.
There are many places you can upload your raw DNA, and several of them are free. Popular third-party DNA analysis tools include GEDmatch and Promethese. GEDmatch is a free, open database and genealogy site that gives additional DNA relative matching and trait results. This tool has information from users of multiple different testing companies. Promethease compares your raw DNA information against scientific reports that link certain markers to health conditions, though you should take these results with a grain of salt as genetic links do not equal a diagnosis.
The technique of DNA profiling was developed by Alec Jefferys in the mid-1980s and is based on the analysis of markers in DNA known as microsatellites or Short Tandem Repeats (STRs). These markers are found at specific points (also called loci) in everyone’s DNA and they’re motifs of two-six bases (the units that make up our genes) that are repeated numerous times. The exact number of times these markers are repeated differs between individuals, but members of a family will share the same or a similar number of repeated markers, depending on how closely related they are.
Genes make up the blueprint for our bodies, governing factors such as growth, development and functioning. Almost every cell in the human body contains a copy of the blueprint, stored inside a special sac called the nucleus. The estimated 23,000 genes are beaded along tightly bundled strands of a chemical substance called deoxyribonucleic acid (DNA). These strands are known as chromosomes. Humans have 46 paired chromosomes (half inherited from each parent), with two sex chromosomes that decide gender and 44 chromosomes that dictate other factors. Certain portions of DNA are unique to each individual. DNA profiling is a way of establishing identity and is used in a variety of ways, such as finding out whether twins are fraternal or identical. DNA samples are usually obtained from blood.

Is this a perfect method?  No, but it’s a good way to get a general idea about where your ancestors were from.  Genealogical DNA tests can tell you a lot about your ancestry going back 300-500 years in time, for the most part.  They can also tell you a little bit about your ancestry going even further back.  This is why comparing your DNA to those whose families have stayed in a particular area for a long time is a fairly accurate way to perform the estimate.
A genetic counselor, a healthcare professional with special training in genetic conditions, will be able to answer your questions and help you make an informed choice. We recommend that you speak with a genetic counselor before testing, and also after testing to help you understand your results and what actions you should take. This is especially important for health conditions that are preventable or treatable.

A friend of mine knew I had been working on my family history and bought me an AncestryDNA kit for my birthday. My results were surprising to say the least. I discovered I’m 35% Native American, 5% African and 29% from the Iberian Peninsula. This has drastically broadened the way I think about my identity and heritage. I feel connected to those parts of the world now and I’m excited to see how far back our records can go.
When it comes to proving a biological relationship between a British citizen and a family member living abroad so that they may immigrate, DNA testing can greatly strengthen the case. However, DNA evidence alone does not guarantee a successful immigration application. If you’re considering taking a DNA test for immigration purposes, we recommend you take legal advice to ensure it’s used in the best possible way.
In our tests, we did find consistency across our results on the continental level. For example, my ancestry is exclusively East Asian, but 23andMe breaks it down into 80 percent Korean, 10.5 percent Japanese and 0.8 percent Chinese, with the remaining 8.7 percent in broader categories. However, Ancestry reports my DNA as 98 percent Korean and Northern Chinese, with only 2 percent Japanese. National Geographic places 85 percent of my ancestry from Northeastern Asia and 14 percent from the South China Sea region, with my DNA most closely matching the Korean and Japanese reference populations.
And that’s where it starts getting interesting, because then we can start comparing that genetic signature to the results from other men who share the same surname but don’t appear on our family tree. If the matches are close, then we can start thinking “is there a common ancestor for these families another generation or two back? Are the families linked in some way?”. Depending on what we already know about either family group, it can help target the paper research to get those families linked, or take us back another generation or two.
×