Though it goes without saying that a sibling relationship is built upon a lot more than just shared genetics, achieving a definitive answer will bring along a myriad of benefits, including the peace of mind that you finally ‘know.’
A sibling DNA test is most ideal in situations where two parties mutually agree that they want to confirm whether they are full siblings, half-siblings, or not siblings at all. They require swabs of DNA from both alleged siblings, where they get rigorously tested in a laboratory before being sent back with an answer.
Of course, there are plenty of other reasons why you might be interested in purchasing a sibling DNA kit. In fact, they’re commonly used to aid in court cases.
Whatever the reason, this guide will provide you with a review of some of the best sibling DNA testing kits in order to help you determine which one is best for your personal circumstances.
When Should You Get a Sibling DNA Test?
The most natural time to get a sibling DNA test is when two people want to figure out whether or not they are siblings by blood. There are two most common types of sibling tests available to purchase, which are as follows:
Ancestry DNA Test Kits
An ancestry DNA kit is a reliable way to prove that two alleged siblings share one or two of the same parents. These types of kits are more so used when two people simply want an answer, as opposed to needing the information for legal purposes, as they are not court-admissible.
Furthermore, ancestry DNA kits will also be able to provide additional background information about your ethnicity and lineage.
Dedicated Sibling DNA Tests
On the other hand, dedicated sibling DNA tests are designed with the sole purpose of legally proving that two people are siblings, half-siblings or not siblings. These kits are court-admissible and are usually the most affordable out of the two kinds.
When looking for the best DNA tests to fit your budget, your personal goals, and the overall scope of your genetic exploration, researching all the available options is of paramount importance. The following mini-reviews will familiarize you with the top at-home testing solutions currently on the market.
Our Top Pick Is Accurate and Accredited
My Forever DNA Sibling DNA Test can accurately determine whether or not two siblings are full, half, or unrelated. The price includes all lab fees and shipping costs and offers a turnaround time of 1-3 days as opposed to competing kits, which can take up to two weeks.
Here’s a quick breakdown of what this kit offers:
- Besides the test, the price of My Forever DNA Sibling Test covers all of the lab fees and shipping costs, so you do not have to worry about being charged any unexpected, additional fees at a later date.
- My Forever states that they offer a 99.99% accuracy rate, and test 46 DNA markers as well as gender identification markers to ensure accuracy.
- The contracted lab is located in the USA and boasts one of the best accreditations: the AABB Accredited, Annual Participates in the College of American Pathologists, so you can be confident in the credibility of this company.
- Before results are sent back to you, each test is carefully checked over and signed off by My Forever’s Chief Scientific Officer that has over 15 years of experience in DNA sibling testing.
- My Forever offers excellent customer service and a quick turnaround of 1-3 days.
My Forever DNA Sibling Test
Offering a fast turnaround time and reliable results, the My Forever DNA Sibling Test is the gold standard of sibling DNA testing.
If you suspect that you may share a parent with someone, the My Forever DNA Sibling Test will help you to determine whether the both of you are half or full siblings, or not siblings at all.
Offering the greatest accuracy, this sibling DNA test is 99.99% accurate and uses over 46 markers during the testing process. This is super impressive, especially considering that most companies only test between 15-30 DNA genetic markers.
In addition to the 46 markers, My Forever also makes sure to test any anomalies twice to reduce the chances of any false negatives or false positives. Your results will take 1-3 days to get back to you and are held in the strictest confidence, so they will only be made available to you.
When the kit arrives, all you and your sibling will have to do is follow the step-by-step instructions that will guide you on how to take your saliva cheek swab, along with the additions of mouth swabs. It’s pain-free and will take only a few minutes to complete.
What’s more, the price you pay includes lab fees and the cost of shipping your DNA swabs to the My Forever lab, so you don’t have to worry about dealing with any unexpected fees. Plus, if you do have any questions that need answering, you can reach out to their customer service team, who has garnered plenty of positive feedback from customers online.
Pros
- 99.99% accuracy rate
- It has the quickest turnaround time we’ve seen, and you’ll get the answer emailed back to you within 1-3 days
- Before getting sent back to you, the Chief Scientific Officer will check the integrity of the test before signing it off
Cons
- Expensive
AncestryDNA: Genetic DNA Test
If you’re interested in finding out additional background information about your ancestry as well as determining whether or not you are siblings with someone, the AncestryDNA Genetic DNA Test is a great option to consider.
We strongly recommend AncestryDNA for taking your sibling DNA test because they maintain the largest DNA database in the world and have over 15 million people recorded on it. Unlike the My Forever DNA Testing Kit, both you and your sibling will have to take the AncestryDNA test separately in order to learn whether or not you are siblings.
After you have both taken the test and received the results, you will be able to check if you appear in each other’s list of DNA matches.
If you are related and you do both features in each other’s list, you can then contact AncestryDNA who will provide more detailed information on whether you are full or half-siblings. This information provided by AncestryDNA will only be accessible to you and your sibling and will remain strictly confidential.
Not just that, the bonus of using this kit is that your matches may also indicate any cousins and relatives you might have never known that you had! By looking further into these matches, you will be able to learn more about your family tree, as well as reaching out to your DNA matches in order to establish new relationships.
After this kit has served its purpose of helping you to identify whether or not you are siblings with someone, you’ll have the option of subscribing to an Ancestry.com subscription that will allow you to learn even more about your ancestry and go further back into your family tree.
You’ll be given unprecedented access to millions of genealogical records that can help you make connections between different relatives or trace any missing relatives. It’s a goldmine of genetic information!
Pros
- It has the largest DNA database, which will raise the chances of you discovering any other relatives
- Besides helping you discover if you’re siblings, this kit also gives you the option to learn more about your ancestry
Cons
- Long turnaround time
23andMe Ancestral Personal Genetic DNA Test
While discovering whether you are siblings or half-siblings, why not take the time to also screen for any health risks that you both might have? The 23andMe Genetic DNA Test will allow you to do just that.
Similarly to the AncestryDNA Test, both you and your sibling will have to take the test separately. When you have both taken it and received your results, you will be able to access 23andMe’s online database where you will be able to view all of your DNA matches.
To ensure total peace of mind, your personal data is encrypted, protected and entirely under your own control. At all times, you can choose what information you want to share, and what information you want to keep to yourself.
Besides opting in to view your DNA matches, you and your sibling will also be able to share information about your health with each other, too.
The turnaround time is longer than average and can take up to 6 weeks. However, besides helping to uncover whether you are siblings, this DNA kit will also provide you with genetic insights that will make it easier for you to effectively take action on your health.
Pros
- You can learn how your DNA can affect your health
- Suitable for confirming siblingship, both of you can take the test and check to see if you’re a match via their online database
Cons
- This kit tells you about potential health risks you may be prone to developing, and some people may not wish to know this
FamilyTreeDNA Ancestry Family Finder DNA Test
If you’re looking for an affordable DNA kit that will help you uncover whether you are siblings with someone, the FamilyTreeDNA’s Family Finder Test will provide you with a variety of powerful, interactive tools that will help you find your relatives and trace your lineage through time.
If you and your potential sibling both take FTDNA’s FamilyFinder test separately, you can determine your siblingship by checking to see if you are DNA matches using FTDNA’s online DNA matching database.
Once the kit arrives and you both separately send in your samples, you’ll need to wait 6-8 weeks before your results are ready to be viewed. It takes much longer than solely sibling DNA tests because the FTDNA testing system goes far deeper than just checking for shared siblingship.
To determine whether someone is a sibling, all you’ll need to do is check to see if their name shows up on your matches list. If you are siblings, they’ll feature high up on your list, as they’ll be classed as a close relative.
As a general rule of thumb, if you’re full siblings then will share between around 2,000 centimorgans, which is a unit used by FTDNA to measure genetic links. If you are half-siblings, the amount will be around 1,800 centimorgans. If you don’t see your potential sibling listed in your list of matches and they don’t see you either, then it is highly likely you are not related.
Your genetic report will also provide you with information on your lineage and how much autosomal DNA you still carry, such as from the Bronze age and Neolithic hunter and gatherers.
Pros
- Offering the best value for money, the kits come with a return shipping envelope, and your order also includes a prepaid return shipping label
- The FamilyTreeDNA database will provide you with a matches list that will help you learn if you are full or half-siblings
- You’ll discover information about your ancestry and how much autosomal DNA you carry of the ancient European groups
Cons
- You and your sibling will need to take the test separately
How to Choose Sibling DNA Tests
Marker Accuracy
When you’re choosing a sibling DNA test, accuracy needs to be at the top of your priority list. But, what’s a good indication of accuracy? It can be hard to figure out, especially if you’re not familiar with DNA kits and the companies testing reputability.
Generally speaking, the higher the number of markers the company tests in the lab, the more accurate the results you get back are going to be. Most DNA testing companies will test anywhere between 15 to 30 genetic markers when testing whether or not two people share parents.
We strongly recommend selecting a company that will test 20+ markers, as this ensures more accurate results that aren’t going to be incorrectly swayed by false negatives or positives.
Company Reputability
How reputable is the company that you’re planning on buying from? This is an important factor to consider before making a decision. We strongly recommend avoiding tests that have garnered poor reviews online, or companies that have poor customer service.
All the tests that we have talked about today are established and well-respected.
The Wait Time
The best DNA testing companies will have a pretty quick turnaround of around 3-5 days.
However, it’s important to remember that the turnaround time will begin when the lab receives and then begins to process your sample. Therefore, in total, it’s probably going to take you anywhere from 1-2 weeks to receive your answer.
Data Protection
This one is very important! Make sure that you read the company’s privacy policy before you order a DNA test. Your DNA information should remain confidential and secure at all times. If a company says they retain the right to share or sell it with third parties, that’s a clear indication to not purchase from that company.
All the tests that we have selected will provide a high level of privacy and confidentiality to you.
Tips on Raising the Accuracy of Your Results
Sibling DNA tests compare more markers than any other type of DNA test to improve testing accuracy The reason for this is because siblings are more closely related to their parents than they are to each other, which can make finding genetic links harder.
Whether you’re getting a sibling DNA test just to know for definite, or you have to do so for legal reasons, here are a few tips for improving the accuracy of the results you get:
- Make sure that the company you select will use over 20 markers to test. Though you may be tempted to go for a cheaper DNA testing kit, they’re more likely to only test 15 markers, which raises the chances of false negatives and false positives giving the wrong answer.
- If you suspect you could be half-siblings, if possible we suggest having the shared parent take the test, too. Many companies will allow you to add the shared parent’s DNA into the sample for testing. For more general ancestry kits, they’ll have to take the test themselves.
- In the case of two male siblings wanting to discover whether or not they share the same father, we suggest getting a Y-DNA test, and FTDNA provides a reputable Y-DNA kit. This is more accurate for males as the Y-chromosome rarely changes when passed down from father to son. If two make siblings have the same Y-chromosome, then it can be strongly assumed that they have the same father.
- For any two siblings, male or female, wondering whether they share a mother, get an mtDNA test, again, FTDNA provides a trustworthy one. Unlike a Y-DNA test, this one will compare the mitochondrial DNA passed down from the mom. Just like Y-DNA, the mitochondrial barely changes as it is passed down. For this reason, two people that have the same mtDNA have the same mother.
Frequently Asked Questions
How does a sibling DNA test discover if two people are siblings?
Though the testing process is highly regulated, companies actually follow a pretty simple system! When they receive the DNA swabs, they will carefully compare the genetic markers between the two parties.
If they share roughly 50% of their DNA, this means that they are full siblings. If they share 25% of their DNA, then this means that they are half-siblings. If they share very little of their DNA, they are not related.
How accurate is a sibling DNA test?
Paternity tests are generally more accurate because it is much easier to compare a child to their parent.
The accuracy of a sibling DNA test will depend on how many locations the lab compares. The minimum is usually 15 or 16. The ideal range is 20-30.
For extra accuracy, look for a company that tests at least 40 markers.
But no matter how many markers a lab tests, no DNA test is 100% accurate. In fact, your sibling DNA result will be a probability.
In most cases, a high probability is almost a guarantee that they are your sibling. But there is always a small chance that they might not.
Is it possible for full siblings to have different DNA?
Yes, siblings can have different DNA! Each sibling gets around 50% of their DNA from each parent, although the amount given from each parent can vary.
This is for multiple reasons. The main reason is due to a gene process called recombination (which is when genes shuffle around during fertilization of an egg).
For this reason, the mother could pass on a different combination of genes to one sibling than she could to the other. The same gene reshuffling happens with the father, and this is how DNA can differ from sibling to sibling. This is often why full siblings only share around 50% of the same DNA.
Can Sibling DNA Testing Kits be Incorrect?
All DNA testing kits can provide an inaccurate result, although this is usually very rare. The main reason for inaccurate reading is when a company only tests a low amount of markers, which can lead to a false negative or false positive. If you do have doubts about your results, we recommend testing with another company, just to be sure.
Can sibling DNA testing kits be used for half-siblings?
Yes, absolutely. The lab you choose will check both your genetic markers and compare them to see if you share roughly 25% of your DNA. If you do share this amount, then it can be assumed that you are half-siblings. If you share more DNA (around 50%) then this would mean that you are full siblings.
However, if you share less than 25%, it could mean that you are cousins.
What percentage of DNA do half-siblings share?
If you’re half-siblings, then you will share around 25% of your sibling’s DNA.