How To Interpret DNA Test Results

So you have taken the genetic test and received results; what now? Interpreting DNA test results can be confusing. Genetic testing options are constantly changing, and it is important to understand the implications of your genetic testing results.

We take pride in keeping up to date with the latest developments when it comes to analyzing your results so that you can take the next important steps to find out about your health, genealogy and even paternity.

Quick Overview

DNA tests have become widely popular over the last several years, as more people are determined to discover their ancestry.

Depending on the type of genetic test you had, the terms “positive”, “negative”, and “inconclusive” can mean many different things. Companies like 23andMe, AncestryDNA, MyHeritage and Family Tree DNA offer cost-effective at-home testing that delivers results to your email inbox within a few weeks.

Results of clinical testing may come to you through your healthcare provider.

Many genetic tests focus on origins and ethnic mapping but there are some tailored to discovering health issues, including identifying variants that may signify whether a person is a carrier or is at a higher risk for specific diseases.

Other DNA tests are used to determine paternity when it’s called into question. Regardless of the type of test you take, knowing how to interpret the results is beneficial in understanding the reports.

Interpreting DNA Test Results

After you've taken the DNA test, whether it's for ethnic mapping, health, weight or even paternity-based, you'll receive a report that lists the findings.

These reports are highly detailed, and while they do use a lot of scientific jargon, they’re easily broken down into layman’s terms so you can understand the specific components.

The more specialized the test you take, the more specific your end results will be. Most reports come with a key that explains each factor and how it relates to your DNA.

Are DNA Results Accurate?

There are a lot of factors that go into evaluating your DNA and external elements that can skew your results. However, the testing itself is precise, so you can rest assured that your results will be fairly accurate, though they will never be 100 percent.

Several stories have emerged about people who have taken DNA tests from different companies and ended up with varying results. Does this mean that one is more accurate than another?

No, it simply means that these companies are likely testing different factors in the DNA ¹. Typically, your ethnic estimate will generally be the same with slight variations among companies, particularly if they dial into specific regions.

Interpreting Possible Matches

When it comes to interpreting possible familial matches, DNA companies essentially compare common DNA among those who submit their samples. By doing this, they identify a similar code that may indicate your relationship to someone else in the database.

Many of these matches are distant, which makes sense because a person's ancestry dates back thousands of years and having similar ancestors will lead to these matches.

Siblings and first cousins will have a higher percentage of matched DNA, where distant cousins, aunts and uncles will have lower percentages, including some that come in with under 1 percent match rates ².

Do You Need Genetic Counseling?

Genetic counseling is a personal choice that each person has to make, though it can be beneficial for some more than others.

Genetic testing is a small piece of a genetic risk assessment. Those that are seeking out health information should see a genetic counselor, especially if there is a personal or family history of a specific condition.

Genetic counseling may also be beneficial to those with a health related genetic change on a Direct-to-Consumer (DTC) genetic testing report as additional testing may be necessary.

Genetic counselors can also discuss how genetic testing may affect other family members, psychosocial issues related to genetic testing, and how this testing could affect your insurance policies.

What Is a Genetic Counselor?

A genetic counselor is a medical specialist who is well-versed in genetics and how they affect you and your direct descendants. They can help you navigate your results and even recommend more testing that provides additional insight into inherited conditions and diseases ³.

You’ll also have access to information that can help you make informed decisions about your family, such as family planning options or how to go about preventing certain health issues.

Not all genetic counselors work in the same niche, some choose to specialize in different areas such as neurology, cancer, pediatric and prenatal fields.

Others prefer to dedicate themselves to research with the hopes of advancing medical knowledge to help even more with genetic conditions in the future.

All genetic counselors can help you navigate the genetic testing process to help you make decisions that best suit your needs.

What Is a Positive Test Result?

A positive test result indicates different things for different tests.

For example, if you’re taking a health-based DNA test, a positive result could mean that you have specific gene changes, also known as gene variants or mutations.

Examples of these gene changes may relate to diseases such as Cystic fibrosis or certain types of cancer.

These gene changes can be inherited from a parent. However, some gene changes are not inherited and occur in the first time in you (de novo).

Depending on the condition, positive results don’t necessarily mean that you’ll develop the disease, but you and your family members may be at a greater risk than others to develop the condition.

With a paternity test, a positive test result simply means that the child tested against your DNA has proven to be related to you.

What Percentage Does a Paternity DNA Test Have to Be to Be Positive?

In order to be considered a positive match, a DNA test has to range between 99 and 99.99 percent. Anything below that and the results will display that the person is excluded as the father.

This is a scientific term that basically states the male tested cannot be accepted as the biological father because the science does not support the relationship.

What Does 99.99 Mean on a DNA Test?

Receiving a 99.99 percent match on a DNA test signifies that there is very little doubt that the person taking the DNA test is the father of the child. This is measured through the Combined Paternity Index, or CPI.

However, the test results will not outright say you are the father, it will be scientifically stated as "not excluded," which means your genetic makeup matches the child's with enough accuracy to determine that you're the alleged father.

What Is a Negative Test Result?

A negative test result when it comes to DNA testing, like a positive result, can have multiple meanings.

However, it typically means that there are no genetic changes or mutations detected that indicate the presence of, or that a person is a carrier of a certain disease. It can also mean that a person is not at an increased risk based on genetic factors.

For most negative tests, further testing may be necessary in order to confirm the result. This should typically be done in a lab under the guidance of a qualified physician or genetic counselor, especially if it warrants further review.

What Is an Inconclusive Test Result?

An inconclusive test result can be frustrating because it gives no real insight into your DNA either way.

It cannot tell you if you're at a higher risk for certain diseases but it can't rule it out either, so you're left with no real answer and no means of evaluating your results. If you end up with an inconclusive result, don't despair.

Instead focus on those that are conclusive and consider scheduling a follow-up with a genetic counselor if you’re that dedicated to wanting to learn more about your genes and potential risk factors.

If you did an at-home test, maybe you’ll want to schedule one with your doctor or a genetic counselor.

Why Would a DNA Test Be Inconclusive?

There are several reasons why your DNA test might be inconclusive, depending on the type of test that you're taking. For paternity tests, any range that extends from above 0 to 98.99 percent is considered inconclusive.

This often occurs because there isn't enough DNA to compile or there aren't enough matches in the DNA to come up with a positive result. For this reason, if the paternity isn't verified, but the lab technicians need more data, they'll include the mother's DNA in the test as well.

This makes it easy for them to eliminate the mother's DNA to hopefully form a stronger match with the potential father. It can also go the other way and completely eliminate him as a potential candidate ⁴.

For health tests, on the other hand, the factors are a bit different so there are varying reasons why the results can come back as indeterminate.

The most common reason is that there are variations that occur in a person’s DNA and more information is needed to determine if this variant is related to a disease or disorder.

Sometimes, the best way to overcome this is to have family members undergo testing for the same variant. This can include those family members that are affected and unaffected.

Other times, additional research is needed for laboratories to piece together evidence about the variant.

Another reason for indeterminate results is contamination of the DNA sample. This can happen when the sample is handled improperly.

Finally, inconclusive results may occur if the sample size is too small. In cases of contamination or too small of a sample, you’ll have to do the testing once again.

Interpreting Paternity DNA Test Results

If you've had to undergo a paternity DNA test, you are probably familiar with the process which involves a cheek swab of both the alleged father and the child or children in question.

The test is pretty straightforward and compares both sets of DNA looking for commonalities that indicate the presence of a relationship between the two.

Paternity 'Not Excluded’

Paternity 'not excluded' is a scientific term that indicates the probability of paternity is enough that the man is not being excluded as being the father of the child. This is only listed if the match is between 99 and 99.99 percent. These results are the closest you'll get to a positive.

Paternity ‘Excluded'

Paternity excluded means that there is not enough evidence to support a relationship between the alleged father and the child. In this case, a court would rule that the person is not the father and would not recognize him as the biological parent.

Can the Probability of Relationship Ever Be 100%?

The probability of paternity can be 100 percent, but not in a positive manner. If the result is 0 percent, it's considered that the person tested is 100 percent not the father.

There will never be a 100 percent positive result; the highest match for a paternity 'not excluded' result is 99.99 percent.

Interpreting Ethnicity DNA Test Results

All of the at-home DNA ancestry tests you take will include your ethnicity results, pinpointing the regions that your genetic makeup indicates.

For some people, learning their ethnic regions comes as a great surprise, while others are confident in theirs, knowing their genealogy quite well. These results give you an insight into where your ancestors originated from.

They can be limited to a specific region or spread across the globe, depending on your roots. In general, you’ll see a list of regions with a percentage next to them to indicate how much of your genetic makeup comes from that ethnic region.

Some results may even include low confidence regions, which are those that the test cannot pinpoint with certainty using your DNA. They are often the lowest percentages on your list.

It is important to remember that just because your DNA doesn’t reflect ancestors you thought you had, it doesn’t necessary mean that you weren’t related to them. This simply means you may not have inherited much of their DNA.

How Do Maps From Different DNA Testing Companies Compare?

Your ethnicity estimate is a ballpark figure but could vary among companies. If they're doing the same test, how could they possibly be different you might be wondering.

The truth lies in the number of regions and the type of technology that each DNA testing company uses. MyHeritage DNA, for example, uses 42 regions while 23andMe has continued to add more than 100 over the years and includes sub-regions to more accurately pinpoint your ancestry.

Interpreting Ethnicity Maps

The ethnicity maps for DNA testing companies tend to be interactive, meaning you can click on the regions to get more information about the area and what your ancestors were like in the past as well as how they landed in that region.

The ethnicity maps also tell you which countries fall into those regions and some companies even pinpoint the exact location your DNA outlines.

What Are Reference Panels?

Reference panels are a means of proving your ancestry with 100 percent certainty. They are a glimpse into an extensive family history that includes those who date back thousands of years.

If you're certain of your history, you can apply to be on the reference panel and log your name for future generations to discover. It's not a simple task though, and not just anyone can do it.

You do need a paper trail that proves your connection and only after this is established, you will need a DNA test as confirmation.

Interpreting Health DNA Test Results

One aspect of DNA testing that tends to spark a lot of emotion is testing for health factors.

This is especially true if you're looking to see if you are a carrier for a disease or condition, or if you have inherited gene mutations that indicate you'll potentially or definitely develop a condition or disease in the future.

Is It Possible to Get False Positives?

When it comes to taking any kind of test, there is always room for error. For this reason, there is the potential that false positives may occur.

One study even identified a 40 percent error rate that led to false positives. This only exemplifies the importance of going over your results with a qualified professional.

What Does Zero Variants Detected Mean?

When the test results say “zero variants detected” it means that there are no mutations detected that signify an increased risk of a specific condition or disease. However, this does not mean that you are not at risk to be a carrier.

What Does It Mean to Be a Carrier of a Disease?

Being a carrier typically means that there is a risk for you to have a child with the specific condition. Most of the time, this means that your partner should also be tested to determine the risk to future children.

It is very important to discuss this with your healthcare provider to ensure that your partner receives the right genetic test, since it may be different from the test you had.

Carriers can still have healthy, unaffected children. The risks and additional testing can be discussed with a genetic counselor.

Should You Analyze Your Health DNA Test Results or Let a Professional Analyze Them?

While you’re given enough information to determine your results on your own, sometimes the context is best analyzed by a qualified doctor or genetic counselor.

For this reason, most companies have a fine print text that says the results are only for educational and informational purposes.

Not all health DNA tests are created equal. Instead of trying to figure out what your markers mean for you and your family's future, seek out the help of a professional to evaluate your results.

What to Do If Your DNA Reports Are Not What You Expected

Sometimes the results you get are exactly what you suspected, while other times they may throw you for a loop.

If you've spent your entire life hearing about how your great-grandparents are from Ireland, you might undoubtedly be a bit surprised if your results show up showing a very low percentage of Irish ancestry.

That doesn't mean that your family lied to you, it simply means you didn't inherit much of that ethnicity.

It's possible that you and your siblings have different percentages of ethnic makeup, and this is very normal. You do get 50 percent DNA from each parent, but that DNA can and often does differ among children.

This is the reason why you may have brown eyes, but your sibling's are blue.

Other things that might take you by surprise are the presence of genes for inherited conditions or increased risks for serious diseases, even if there is no history in your family.

One thing to note, though, is that the presence of these markers does not necessarily mean you'll develop the disease.

Some just outline the risks, so don't be rash in making any decisions about your present or future. Instead, take the opportunity to speak with your doctor or a genetic counselor for a more accurate representation of what the markers mean for you and potentially, your family. ⁵.

Tools to Analyze Your DNA

Here are a few sites that are available when it comes to analyzing your DNA reports.

They all work essentially the same way: you upload your raw data and then select the services you want to use. Some are free while others charge a fee for their services.

Some also offer a combination of free and paid options so you can return at a later date and upgrade your services.

It is important to realize that many of these sites are not recommended by clinical professionals since they are not typically following the standards of clinical testing and they do not go through the thorough process of analyzing the data that a certified, clinical lab would.

It’s best to discuss this with a genetic counselor.

GEDmatch

GEDmatch, found at gedmatch.com, has several options on their site. After uploading your raw data you can choose from varying analyses including:

• Matches including one-to-one, one-to-many, X one-to-one
• Phasing, including phasing for DNA that you didn't inherit
• Admixture
• Triangulation
• Relationship Tree projections

The company offers two services: basic memberships, which are free and Tier 1 utilities which are available for $10 monthly as of January 2019.

GEDmatch works with analyses from 23andMe, AncestryDNA as well as FTDNA, though some services are limited to 23andMe only. You'll need the kit number to get started.

Genetic Genie

Found at geneticgenie.org, this site is very specific in the analyses that it provides. It also only works with 23andMe tests, so be aware of that if you're trying to use their services. You can upload your raw data to receive your:

• Methylation Analysis
• Detox Profile

At the present, there are no costs associated with using these services, though they do ask that you consider donating to help offset the costs of maintaining the website.

Promethease

If you're looking to research and learn more about what your DNA profile says about you, you'll get a lot of information from promethease.com. Here you can upload raw data from nearly any DNA testing service, which makes it a universal resource.

The site does warn that the detailed reports are for informational purposes only and to speak with a doctor or genetic counselor about any concerning issues that may appear. Some of the information you'll receive:

• Genealogical details
• Health information to gauge genetic risks
• Titles of scientific literature to reference for better understanding

The site doesn't take long to generate your report, you'll have access to it within 15 minutes. As of January 2019, the reports cost $12, though you can add another data file to create combined reports for an additional $4.

If you want the combined reports, you have to pay for them at the same time.

Interpretome

Interpretome works with data files from two specific companies: Lumigenix and 23andMe. It gives a comprehensive analysis that determines:

• Your health risks for specific diseases including Type 2 Diabetes, Alzheimer's and Lewy body disease to name a few
• Genealogy results

The site cautions against taking the results as diagnostic, rather their reports are meant to be informational in nature for educational purposes only.

Genomapp

Genomapp is an app designed to work on your Android or iOS device. You upload your DNA data to get your comprehensive report in just 5 minutes. Things included in your report include:

• Methylation
• Inherited Conditions
• Complex Diseases
• Traits
• Blood Groups

There is a small fee associated with exporting your report as a PDF, though it tends to be hidden until you request it.

Whether you're taking your first DNA test or comparing your results against different companies, you definitely want to know how to interpret the results to get a full understanding of the factors that go into testing.

Your DNA is processed into what's known as raw data, which you can plug into one of many tools for a more thorough explanation of what your genes are trying to tell you.

However, it is best to seek out the help of a genetic counselor to go through this process to help find reputable tools and discuss privacy issues that may be related to these tools.

Genealogy and health DNA tests go into far more detail than your standard paternity tests because they’re seeking out the information held within specific addresses of your genetic information, whereas paternity tests are looking for commonality.

Knowing how to appropriately interpret the results gives you more power to make educated decisions about your current lifestyle and your future.