DNA testing examines the genetic code that’s carried in every person’s unique DNA profile. The code can be found in the cells of any human material, from a drop of saliva to a smear of blood or a strand of hair.
How Does DNA Testing Work?
DNA testing works by taking a sample of cells from the person who’s undergoing the test. Scientists isolate the DNA code that is at the heart of every single cell and carries the information which determines all of your physical characteristics, from your hair color and height to your chances of developing certain conditions.
How Do I Use the Kit?
If you use a home DNA testing kit, you’ll find all the instructions included. Usually, you’ll be sent a sterile tube to collect your saliva sample. It can be awkward to get enough spit for the test purposes. Some companies send a cheek swab that you rub against the inside of your cheek to get a sample of cells from there, instead.
Once you've collected your DNA sample, you'll seal it into the sterile package and use the included mailing package to send it back to the company. It usually takes a few weeks to get the results, but the time frame varies; it can be anything from 4 to 12 weeks.
When your results are ready, you’ll typically get an email inviting you to view the results online. Ancestry DNA companies have a dashboard that lets you explore your results.
Types of DNA Tests
A DNA sample can reveal many different facets of a person depending on how it’s tested and what the analysts are looking for. These can range from ancestral roots to biological parents and health predispositions. Here’s a look at some of the more popular tests than can be run on your DNA:
Paternity tests are used to confirm who is the father of a baby, child, or adult.
Genealogy or ancestry tests are used by genealogists to determine ancestral ethnicity and relationships.
Health tests can determine how your body works, as in the case of metabolism and processing vitamins and nutrients, to what risks are at play in developing common diseases.
Gene therapy DNA testing is most commonly used for parents before they try to conceive or for fetuses to check for inheritable genetic conditions, or if an embryo is carrying any birth defects.
Forensic DNA tests are used by police at crime scenes in order to identify victims or find criminals after certain crimes.
How to Choose a DNA Test Kit
Like countless other purchases in life, when it comes to ordering a home DNA kit, it’s crucial you determine what’s most important for you. Here are the key considerations to look for when you choose a DNA testing company or a DNA testing kit.
1) What the test reveals
If you’re most interested in family genealogical research, your best bet would be to go with a company like MyHeritage or AncestryDNA. With both of these companies you can also access a massive database of billions of historical records, as well as trace your roots through the family tree builder. In addition, the companies have millions and millions of users in their databases and can match you with relatives, so if you’re looking to find long lost family members, companies like these are your best bet.
If you’re looking to learn more about your personal health and also perhaps get tips for nutrition and exercise, then companies like Vitagene, 23andMe and Orig3n may be better options. Other than 23andMe—which combines ancestry mapping with health assessments—the kits aren’t marketed toward users who are interested in deep, extensive genealogical research, rather, they are interested in learning about their health through DNA testing.
Finally, you should also consider how important it is to you that the company does more than just autosomal testing and if it travels across enough geographic regions for mapping your ancestry, or if you want a company like GPSorigins, which looks at more than 900 geographic regions.
2) Type of test
If you want a DNA test in order to learn more about your family and your origins, you have a few options. An autosomal DNA test checks only 22 out of the 23 pairs of chromosomes and can be used to compare DNA from both males and females, so it's best for finding a range of living relatives. It gets less reliable the further back you go because of autosomal DNA changes every generation, so it's only good for identifying up to third or sometimes fourth cousins, and can only give reliable information back to your great-great-grandparents.
A mitochondrial DNA (mtDNA) test checks the tiny mitochondrial strands inside every cell. Both males and females inherit these mitochondria from their maternal line. It can be extended much further back in time because it doesn't change quickly. It gives very precise details about your ancestors and distant cousins – even your 48th cousin! – but only if they lie on your maternal line. It’s good for proving you come from a particular region, ethnicity, or family group but not for finding relatives.
Y-DNA testing examines only the genetic information in the Y-chromosome, which is only found in males. It also does not change quickly, so like mtDNA, Y-DNA testing is good for proving relationship to a common ancestor or checking relationship with another individual, but it only works along the male or paternal line. This also means that only men can do a Y-DNA test, although women could ask a close male relative to take the Y-DNA test and then share the results.
The price of the DNA test varies between different companies as well as depending on the type of test you take. mtDNA tests are the most expensive type of DNA testing, while autosomal DNA tests are the lowest cost and Y-DNA tests come in somewhere between the 2. Although the tests are more or less the same, there’s a huge fluctuation in price between different companies, so compare prices before you buy. Some companies, like LivingDNA, offer a package of all 3 tests for a discount.
4) Ease of Use
Most DNA testing kits are pretty straightforward, but some elderly or weak individuals can find spit tests awkward to use. In those cases, companies that offer a cheek swab for taking samples instead of needing a saliva sample could be easier.
Not every company offers the same range of reports. Very few genealogical DNA testing companies will include health and wellness reports. Most companies provide ancestral reports, which break down your family heritage, ethnicity, and which region of the world you hail from, although some are more detailed than others. Some also provide a chromosomal browser which lets you compare your genetic profile with that of others from around the world. You can also find cousin matching reports, which let you know if you have any matches with other people registered with the same service.
6) Test Accuracy
The type of test you choose affects the accuracy since autosomal DNA tests are less accurate the further back you go but mtDNA and Y-DNA tests remain reliable for dozens of generations. The biggest DNA testing companies such as Ancestry.com, MyHeritage, and LivingDNA are all pretty equally accurate in their test results. However, all companies warn that you shouldn’t use home DNA tests for detailed and critical genetic information like the risk of genetic disorders or of developing cancer.
8) Special Features
As well as these considerations, there are a few extra features that are offered by some DNA testing companies. Some companies store your data indefinitely which means you can discover new family history information 50 years down the line. Others only store it for a certain number of years.
Another feature is the size of the database. The bigger the database of users, the better your chances of finding a match.
Some companies also permit you to upload raw genealogical data to their database so you can see if you have any matches without taking a test again.
Mapping the Story of You
Now that you’ve read more about what the DNA testing industry can provide you, it’s time to get comfortable and find the test that really speaks to you. Genealogy is a fascinating hobby, and it's also a very personal one. You may be more interested in health information than detailed ethnic history, you may want to go deep on genealogical records and track down family relatives across a vast family tree, or you may just want to learn solely about your ethnic makeup. This is a journey that you call the shots on.
You also may find that you can use the DNA information and tools as a sort of jumping off spot for building a full-on family tree. Luckily, a number of companies can set you up with an extensive, intuitive digital family tree which you can update in a flash and even use to meet other relatives online