Orchid’s couple report can tell you about your, your partner’s, and your future children’s chances of developing disease
The couple report from Orchid offers prospective parents the chance to learn how their genetics could affect their own health and the health of their future children. The couple can then decide, based on the results, what actions to take (if any).
The couple report gives two key pieces of information. The first is which diseases the two biological parents have a higher chance of developing. And the second is that same information about their future children.
The current list of diseases Orchid’s couple report tests for includes:
Brain health
Heart health
- Atrial fibrillation (irregular heartbeat)
- Coronary artery disease
Cancer
General health
- Celiac disease
- Class III obesity (BMI over 40)
- Inflammatory bowel disease (IBD)
- Type 1 diabetes
- Type 2 diabetes
Common, chronic diseases like these affect around 45% of the U.S. population.
Because the technology behind the test is new, we get a lot of questions about the report. The top three are:
1. How good is the couple report at predicting disease risk?
Very good. Orchid calculates genetic risk scores to determine your risk for each disease. Large-scale studies have reproducibly found that people with higher genetic risk scores develop disease more often. In addition, genetic risk scores can often predict risk better than clinical risk factors. For example, the genetic risk score for a form of heart disease called coronary artery disease (CAD) can be a better predictor of developing CAD than smoking, high BMI, or even high cholesterol on their own.
2. Are there actions I can take that will lower my risk and my future children’s risk?
Yes there are. With many of the diseases, if you and/or your partner are at a higher risk for a disease, you can make lifestyle changes like eating better or exercising more. You can also make lifestyle decisions for your children when they are born. You can also choose to undergo in vitro fertilization (IVF) and lower the risk for your future children by prioritizing lower risk embryos.
3. Does the couple report work equally well for everyone?
While genetic risk scores work best in people of European descent, they can provide value for everyone no matter their ancestry. Orchid can provide people of European descent with reports on twelve diseases, people of South Asian descent with ten, people of East Asian descent with nine, and people of African descent with two.
For the rest of this article, we will provide information that helps to answer these questions. You can use this information to decide if the test is right for you.
1. How good is the couple report at predicting disease risk?
Very good. Orchid calculates genetic risk scores to determine your risk for each disease. Large-scale studies have reproducibly found that people with higher genetic risk scores develop disease more often. In addition, genetic risk scores can often predict risk better than clinical risk factors. For example, the genetic risk score for a form of heart disease called coronary artery disease (CAD) can be a better predictor of developing CAD than smoking, high BMI, or even high cholesterol on their own.
Orchid’s couple report uses genetic risk scores to calculate your risk for twelve different diseases. Genetic risk scores have been shown to be able to accurately predict who is more likely to develop a disease.
Let’s dig into an example to see just how good genetic risk scores can be–coronary artery disease or CAD. CAD happens when the major arteries that supply the heart are narrowed because of plaque build up. Over 7% of the U.S. population has coronary artery disease and over 380,000 people die from it every year.
If genetic risk scores are meaningful, then more people with a higher genetic risk score should develop that disease. And that is in fact what we see.
In the graph below, people were divided into groups based on their genetic risk score for CAD. Next, the percentage of people in each group who actually developed CAD within each genetic risk score group was calculated. Finally, the percentage of people with the disease was graphed against each genetic risk score:
The blue dots represent the percentage of people who developed CAD at each genetic risk score. The black line represents the predicted percentages based on the genetic risk score.
As you can see, genetic risk scores can accurately predict who actually develops a disease. Also note that even in the highest risk group, only 14% of the people developed CAD. Genetic risk scores cannot tell you if you will develop the disease, only the chance that you will.
Another way to determine how useful genetic risk scores are is to compare them to other known risk factors.
Most people know that high cholesterol, having a high BMI, or smoking all increase your risk for developing heart diseases like CAD. What a lot of people don’t know is that a genetic risk score can be a better predictor of risk than each of these on their own.
A recent study concluded that having a higher genetic risk score had as large or an even larger effect than these other three factors individually.
Let’s focus on BMI. Another study showed that having a BMI of around 30 doubles your risk for developing CAD. A genetic risk score can identify people at higher risk than that.
Genetic risk scores are reported by how much more likely you are to get a disease compared to other people. So if you are in the 97th percentile of risk, you are more likely to develop a disease than 97% of the population.
If you are in the 97th percentile of risk for developing CAD, you are 2.4 times more likely to develop CAD. And if you are in the 99th percentile, the number goes up to 2.8. Both these numbers are higher than the risk because of a BMI of 30.
The following table outlines disease risk for the 97th percentile of risk with an Orchid test for people of European descent (see here for how they perform for other groups).
The odds ratios for the diseases Orchid reports on range from 2.4 to 17.5 for the top 3% of risk for people of European descent. (You can think of the odds ratio as how much more likely you are to develop a disease compared to someone with a typical risk.)
For example, if you are in the 97th percentile for having a BMI of over 40 (class III obesity), then you are over 4 times more likely to have class III obesity compared to the average person. And if you are in the top 1% of risk, your chances are more than 5.5 times higher.
It is important to remember that being in the top 1% of risk does not mean you will have a BMI over 40. It just means you have a higher chance.
You can learn more about how much extra risk a high genetic risk score means for each of the diseases we provide information for in our whitepapers.
2. Are there actions I can take that will lower my risk and my future children’s risk?
Yes there are. With many of the diseases, if you and/or your partner are at a higher risk for a disease, you can make lifestyle changes like eating better or exercising more. You can also make lifestyle decisions for your children when they are born. You can also choose to undergo in vitro fertilization (IVF) and lower the risk for your future children by prioritizing lower risk embryos. We outline these options in detail in this section.
You and your partner
For many diseases there are definitely actions you can take to lower your risk for developing disease.
For example, imagine your DNA makes you more likely to develop type 2 diabetes. You could decide that based on your result you will try harder to maintain a healthy weight, eat right, and exercise more. You may even decide to tell your doctor about the result so you can have your glucose levels tested. All of these actions can help compensate for the genetics you inherited.
With other diseases there is less you can do. If your DNA puts you at a higher risk for Alzheimer’s disease, there isn’t a lot you can do to prevent it. Same thing with type 1 diabetes, schizophrenia, bipolar disorder, and inflammatory bowel disease.
For some diseases, you may already be past the age where risk is the greatest. As two examples, type 1 diabetes tends to develop during childhood and schizophrenia in the early 20’s.
For other diseases that develop later in life, knowing you are at higher risk can still be useful. You can be on the watch for signs of the disease, discuss your higher risk with your doctor, plan for developing these diseases and so on.
Your future children
There are actions you can take for any of your future children who may be at a higher risk for any of the diseases Orchid tests for. You could:
- Choose to do nothing
- Take actions for your child
- Have embryo testing done and prioritize lower risk embryos
Choose to do nothing.
You could choose to do nothing with the result. Remember, the couple report only indicates if you are more likely to have a child with a higher genetic risk. It cannot tell you that your child is at a higher risk.
And even if they are at a higher risk, getting a high genetic risk score does not ensure they will get the disease. Instead, it is just more likely they will.
For some rare diseases, it may not be unreasonable to do nothing. Let’s take schizophrenia as an example.
Around 1 in 200 adults has schizophrenia. This translates to a risk of around 0.5%.
If the genetic risk score suggests a future child could be four times as likely to get the disease, then their risk is 2%. Which means their risk of NOT getting schizophrenia is 98%.
Now it is a different story if schizophrenia runs in your family. If you already have a child with schizophrenia, then your next child has a 10% chance for developing it as well. Being four times as likely to develop schizophrenia means a lot more in that case.
A 3-4 fold higher risk for more common diseases may mean something different as well. For example, around 1 in 8 women will develop breast cancer which translates to a lifetime risk of around 12%.
If the genetic risk score suggests the future child is three times as likely to get breast cancer, then their risk is 36% or more than 1 in 3. That might be significant enough that you want to take additional action.
Take actions for your future child.
Another option if a couple test result comes back with a likely higher risk for a child is to take actions for your children once they are born.
For example, once they reach an appropriate age, you could have their DNA tested to see if they are at higher risk. If they are, then, as we discussed, there are actions you can take for many of these diseases.
If they are at a higher risk for type 2 diabetes, you can help them maintain a healthy weight. If they are at a higher risk for breast or prostate cancer, they can talk to their doctors about options when they are older. If they are at a higher chance of an irregular heartbeat (atrial fibrillation), something simple like an iWatch that monitors their heart would help.
But there are also some diseases for which you can do very little for them knowing they are at a higher risk. You may be able to watch out for certain signs of illness so that treatment can be started sooner. You can also let their doctor know about this increased risk.
Embryo testing.
Another option if a couple test result comes back with a likely higher risk is to use IVF and to use Orchid’s embryo report to test embryos to identify and implant those at lower risk. This action is dependent on genetic risk scores being able to identify lower risk embryos.
It isn’t really possible to directly test how well genetic risk scores work with embryos. The tests have not been around long enough and the diseases we test for can take decades to develop.
So we did the next best thing. We asked how well genetic risk scores work to predict disease in siblings.
Remember, embryos are as similar to each other genetically as are siblings. Or to put it another way, you and your siblings were once embryos with the same parents.
We and others (here and here) have done studies that show siblings with lower genetic risk scores develop disease less often. Here is one of the results from our study:
Sisters with the higher genetic risk score developed breast cancer three times as often as their sisters with a lower genetic risk score. You can learn more about these studies in our guide on sibling attenuation.
We are able to generate similar results for most of the other diseases we test for. This means that it is possible to significantly lower the risk that your future children will develop disease by using IVF and an Orchid embryo test to identify embryos at lower risk.
3. Does the couple report work equally well for everyone?
While genetic risk scores work best in people of European descent, they can provide value for everyone no matter their background.
Here is a list of which diseases we can test for in different populations:
Orchid can provide people of European descent with reports on twelve diseases, people of South Asian descent with ten, people of East Asian descent with nine, and people of African descent with two.
While the couple report can provide results no matter your background, it clearly works better for some ancestries than others. This is because the large genetic databases behind genetic risk scores are made up primarily of people of European descent.
The scientists who run these studies have recognized the lack of genetic diversity in their genetic studies and have started conducting more genetic studies using people of non-European ancestry. One of the most exciting in the U.S. is the All of Us research program. This National Institutes of Health (NIH) sponsored program hopes to enroll a million genetically diverse people.
With programs like these, genetic risk scores should continue to improve and more tests will be available to more people.
Learn more in our guide on ancestry and genetic risk scores.
