In my research into my Cruwys ancestors in Devon, I hit a brick wall trying to find William George Cruwys (born 1821), the brother of my great great grandfather, Thomas Cruwys (born 1831). William disappeared from English records after the 1841 census. I found a William of the right age in Prince Edward Island, Canada, but couldn’t find any records to confirm a link, though naming patterns provided a strong clue.
DNA fingerprinting is commonly used to compare DNA samples taken from the crime scene with those taken from suspects, to either prove or disprove their innocence. In the UK, 10 markers are analysed to produce DNA profiles from the samples taken in criminal investigations. These are then compared to (and stored in) the National DNA Database (NDNAD) to identify if there’s a match. This database currently contains DNA profiles for 10% of the UK population, along with the individuals’ names and ethnicities. Anyone who’s been arrested for a recordable offence has their information recorded on the database, unless they are found innocent or not charged – in these cases, the individuals’ biological samples and corresponding information is destroyed within six months of sample collection.
AncestryDNA recently updated their service, adding new regions and adjusting their algorithm to make their ethnicity estimates more accurate. You're not alone in being a bit bewildered, since plenty of people have had their results change unexpectedly. As genetic ancestry analysis is a relatively recent science and is improving all the time, your results will become more accurate as more people enter the Ancestry database, allowing them to hone their algorithm accordingly.
We evaluated each kit by ordering one, just like any customer would, and tracking how long it took to arrive at the lab and to get processed. Then we compared the breadth and depth of the results to see what rose to the top. The whole process was a lot of fun, in part because of the anticipation of getting the results. Most of the kits warn that testing your DNA can lead to surprising—even life-changing—results. For example, there's the story of a woman who thought she was Irish, but her DNA test revealed she was also European Jewish, Middle Eastern and Eastern European. After diligent research, she discovered that her father, who had died years earlier, had been switched at birth with another child.
The only patients having their genome sequenced are those with certain cancers or rare diseases. In some cases, family members may also be asked to participate. To take part, a patient must first be referred by a consultant, before being taken through an extensive consent process to ensure they know what participation in the project means. As well as the genome sequence, Genomics England asks for access to a patient’s lifetime medical records so that links can be made between their genetics and their individual disease. The NHS has made it very clear that, for many participants, taking part in this project won’t help them treat their disease. But it is hoped that the information they provide will go on to help treat others in the future.
When STR profiling is carried out, the whole of the person’s DNA is not examined. Rather, specific regions (loci) of the DNA which are known to vary greatly between individuals are examined. These loci are areas of the DNA which contain varying numbers of repeating sequences known as short tandem repeats (STRs). It is the number of these repeating units which can differ between individuals. If there are differences between profiles obtained from different samples, the two samples cannot have come from the same person. If, however, the profiles match, then it follows that the samples could have originated from the same person or from any other person who happened to have the same STR profile.Â
FTDNA has, by far, the most advanced tools built-in for easily analyzing cousin matches and it does have a family tree feature that has been recently improved, but most people have not taken advantage of this feature and the family trees found on FTDNA are, when present, generally underdeveloped. However, because FTDNA also provides a host of advanced featured that can provide invaluable data to dedicated researchers their cousin matching system still stands apart from the crowd, drawing in those who are interested in more deeply analyzing their results.
Therefore, when the markers in two samples are analysed, the number of times that they’re repeated can be compared and the statistical likelihood that they came from the same person or from two closely related individuals can be calculated. This is why DNA profiling can be used to establish biological relationships, as well as to connect DNA evidence with a criminal suspect.
We each had two ancestors one generation ago, four ancestors two generations ago, and by the time we’ve gone back five generations, 32 ancestors have each contributed approximately 3% of our autosomal DNA! As an ethnicity test can’t show you how your autosomal segments have been passed from one generation to the next, trying to derive meaningful information about the ethnicities of your ancestors more than five generations ago is virtually impossible.
DNA is found in most cells of the body, including white blood cells, semen, hair roots and body tissue. Traces of DNA can also be detected in body fluids, such as saliva and perspiration because they also contain epithelial cells. Forensic scientists and Police officers collect samples of DNA from crime scenes. DNA can also be collected directly from a person using a mouth swab (which collects inner cheek cells). Find out more in the article Crime scene evidence.
The 100,000 Genomes Project is an NHS initiative, run by Genomics England, and is the largest national genome sequencing project in the world. On entering, patients have their entire genome, of more than 3bn base pairs, sequenced. This is different from commercially available genetic testing kits, such as those from 23andMe, which only look at very small stretches of DNA in a process called genotyping. The hope of the NHS is that having so much genetic information, from so many different people, will allow “groundbreaking discoveries about how diseases work, who could be susceptible to them, how we can treat them, and what treatments might work”.
In Newman’s view, the genie is out of the bottle with home genetic-testing kits. He says that while the kits could potentially provide data in the future, right now, they lack “clinical utility” – they look at genetic variants that, individually, have a very low chance of predicting specific health risks, as there are too many variables: “It’s like the Opportunity Knocks clap-o-meter, with some people further along the scale, and therefore more likely to get the condition and then people at the other end of the scale, who are unlikely to get it.”
When you get your 23andMe results, it takes you to an easy-to-navigate dashboard with your ancestry composition report front and center. Testers reported both high levels of confidence in the accuracy and high rates of satisfaction with the contents and detail of their results. The service breaks down the world into 171 populations, based off its reference panel of 10,000 individuals with known ancestry. Some of these population groups are a tad redundant. For example, I received hits for South Korean, Korean, Broadly Japanese & Korean, and Broadly East Asian in my report, which all represent a similar area but show different levels of certainty. Scrolling down your ancestry summary, you can also view your ancestry timeline. This estimates how many generations back your most recent ancestor from each of your matched regions probably lived. You can also view your ancestry composition mapped out on chromosomes. This view is interesting, as you can change the level of confidence from speculative to conservative, which equates a match percentage of 50 to 90 percent.
The reason that saliva works as well as blood (or hair follicles or skin samples) is that your DNA -- which is short for deoxyribonucleic acid -- is present in all of them. It's the basic genetic code present in all of your cells that makes up your key attributes, from the color of your eyes to the shape of your ears to how susceptible you are to cholesterol.
In testing, we found that many tests have much more specific and detailed results for European ancestry than anywhere else. This is due more to the diversity of the database than size. For example, AncestryDNA has the largest database with over 10 million samples yet results for Asian ancestry are markedly less specific than results from several companies with much smaller databases, including 23andMe and Living DNA.
Living DNA offers the best biogeographical ancestry analysis on the market for people with British ancestry and they are the only company to offer regional breakdowns. With the inclusion of Y-DNA and mtDNA haplogroup information, this is a good all-round test for someone who wants an overview of their genetic ancestry. The test cannot currently be used for genealogical matching, though an autosomal matching service is promised for the future. As a late entrant to the market, Living DNA will start with a smaller database though the test is more likely to appeal to people in the UK, especially those who feel safer keeping their DNA data in Europe.
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.
FTDNA offers Y-DNA (y chromosome, fatherline, men only) and mtDNA (mitochondrial, motherline, everyone) tests. These are separate offerings from the Family Finder test and can be very detailed, depending on the test and option you choose. 23andMe offers mtDNA and Y-DNA as part of their main Ancestry offering, but the results are more limited. Read more about these types of tests here.
Every company on this list promises test results in 6-8 weeks after they receive a sample, except for MyHeritage DNA which claims 3-4 weeks. This can vary however and is influenced by demand and other factors. It is generally a good rule of thumb to anticipate that it will take 2-3 months for results once you order a test. This accounts for the time it takes for you (or your recipient) to receive the test, provide a sample, mail it back and for processing of your results.
It’s worth bearing in mind that when you’re presented with the population groups that have contributed to your DNA, some of the groups revealed may be very general (e.g. Western European) and the report may not tell you when or for how long each group was located in the region that it’s named after. The specificity of the population groups depends on the reference populations used by the company you test with (discussed later). Therefore, if a detailed ethnic breakdown is important to you, look for example reports from the company you’re considering, or get in touch with them to ask for a list of the reference populations that they use.
DNA Clinics will always advise an appointment for your DNA test. However, there are occasions and circumstances when our customers prefer to collect their own mouth swab samples for DNA testing. DNA Clinics self-collection DNA testing kits are available to order by telephone by calling 0800 988 7107 or on-line at www.homednapaternitytest.co.uk. DNA test kits ordered on-line are sent out for FREE. The payment for your chosen DNA test is payable when you return your samples to DNA Clinics.
4. Geno 2.0: At $199 National Geographic’s Genographic Project is the most expensive of all of the choices and is also not deigned specifically for genealogists. They do not offer a database of known relations and the data they provide is more general in nature. However, joining the project does provide a geographic ancestry breakdown as well as a report on how much Neanderthal you may have (fun!). It is an exciting scientific endeavor and definitely worth exploring and joining if you have the resources to do so. Find it here.