Kids Health

What to Know About Genetic Testing and Monitoring Kids for Genetic Illness

written by BIANCA DOTTIN
Source: Rawpixel
Source: Rawpixel

I was diagnosed with a chronic genetic illness at the young age of 27—Polycystic Kidney Disease. When I first received my diagnosis, I had no idea Polycystic Kidney Disease ran in my family. No one in my family was aware of the condition. Getting my diagnosis turned my whole world upside down. I had no idea how to manage my condition and began research immediately to learn. I had to see new specialists and make changes to my lifestyle in order to keep my condition from progressing rapidly.

One of my first concerns after being diagnosed was my children. I had so many questions about what I could do to protect my children or at least find out the odds of them having the same condition. The easiest thing that I knew how to do was make healthy lifestyle changes not only for myself but also for my kids. Once I figured out my main symptoms, I started watching for those same symptoms within my kids. Learning the symptoms was the first important step in monitoring my kids for a genetic illness. If they started experiencing any of the symptoms, I would take them to a specialist to be tested for Polycystic Kidney Disease. 

During my third pregnancy, we were given the option of doing genetic testing because of concerns we had with our previous pregnancy and our family medical history. There were so many options, which made it very overwhelming. Trying to choose the best option of testing when there were so many options available to us was hard. Luckily, we had an amazing genetic counselor at our hospital who was able to walk us through the options. Every test wasn’t necessary for us, and knowing all of our options allowed us to save on costs. The testing we did was super simple.

I had the chance to ask the Director of Genetic Counseling at Juno Diagnostics Katie Sagaser, licensed and certified genetic counselor, for a little advice on what to look for if chronic illnesses run in your family. Below are her answers to some common questions parents may have:

Meet the expert
Katie Sagaser
Licensed and Certified Genetic Counselor and Director of Genetic Counseling at Juno Diagnostics

 

How soon should parents get their children tested for genetic chronic illnesses?

There are many different forms of inherited conditions and other genetic diseases, and the right time for genetic testing largely depends on the presenting concerns of the child and/or family. 

All babies in the United States will have genetic and metabolic testing through the Newborn Screening program in their birth state. This testing occurs within the first 24 hours of life. Conditions included for testing through state newborn screening programs should be well-understood by scientists and physicians, should have treatment available, should have sensitive and specific testing available, and may influence reproductive decision-making of the family in the future.

In other words, a hereditary condition that has no known treatment and affects 1 in every 1,000,000 children would not be included in a state’s newborn screening program. The Advisory Committee on Heritable Disorders in Children and Newborns developed a “panel” of tests recommended to be used in every state called the Recommended Uniform Screening Panel (RUSP). The RUSP consists of 35 core conditions and 26 secondary conditions, which are recommended for newborn screening in each state, but states are not required by federal law to follow these recommendations. It’s important to check your state’s newborn screening program if a condition exists in your family that might or might not be detectable by the newborn screen. 

When a baby is born and no concerns are identified through newborn screening, genetic testing is typically not performed on a child unless a specific concern arises during their development or unless there is a hereditary condition within the family that presents during infancy or childhood. The American Academy of Pediatrics (AAP) and the American College of Medical Genetics and Genomics (ACMG) recommend that genetic testing and screening decisions for children need to be driven “by the best interest of the child” and that genetic testing is “best offered in the context of genetic counseling” to understand the benefits and limitations of such testing.

In general, when a developmental difference is identified in a child, prompt genetic evaluation and testing offer the possibility for earlier diagnosis and intervention if available.

 

newborn

Source: Christian Bowen | Unsplash

 

Is genetic testing something you would suggest during pregnancy or after birth?

Many prospective parents choose to undergo genetic screening and/or testing prior to or during pregnancy, as the information afforded through these evaluations may be helpful to their preparations. It’s important to understand that there is no single genetic test that can predict or rule out all forms of genetic disease, birth differences, or other health conditions. There are, however, a wide variety of screening and testing options to choose from in the preconception and prenatal periods.

The American College of Obstetricians and Gynecologists (ACOG) recommends that all pregnant individuals are offered the option of screening and testing for fetal chromosome conditions. While chromosome conditions such as trisomy 21 (Down syndrome), trisomy 18 (Edwards syndrome), trisomy 13 (Patau syndrome), and others generally do not run in families, collectively, they are observed in about 1 in every 150 live births and even more frequently during early pregnancy. Diagnostic genetic tests for chromosome variations are available through procedures such as chorionic villus sampling (CVS) and amniocentesis.

These procedures offer the ability to obtain diagnostic information about the chromosomal composition of a pregnancy yet carry the possibility of pregnancy loss due to the invasive nature of the procedures. Alternatively, screening for chromosome variations exists through a variety of different non-invasive methods including obstetrical sonograms (ultrasounds), blood tests, and combinations therein. Non-invasive prenatal screening (NIPS) for chromosomal variations through circulating cell-free DNA analysis (also known as “cfDNA screening”) is the most sensitive and specific blood screen for common chromosome conditions, including trisomy 21, trisomy 18, and trisomy 13. Since the chromosomal make-up of a pregnancy is not determined until the sperm fertilizes the egg, fetal chromosome screening and testing cannot be performed prior to conception.

In contrast, it is possible to identify hereditary traits each genetic parent “carries” prior to pregnancy and birth. Since humans inherit one copy of each genetic instruction from the egg cell and the other copy from the sperm cell, sometimes, when one of those genetic copies is altered, there is no impact on that person’s health; instead, they are considered a “carrier” of a genetic condition, which follows “autosomal recessive” inheritance.

Every human is a carrier of at least one autosomal recessive condition—in fact, variations in the spelling of our genetic code are very common and do not always cause health problems! However, when both genetic parents are “carriers” of the same autosomal recessive condition, there is a 1 in 4 (25%) chance that their child will inherit the altered gene copy from each parent, resulting in that child having the genetic diagnosis. Some people choose to have carrier screening during or prior to a pregnancy, as this type of genetic testing can examine as many as several hundred autosomal recessive genes to provide screening-level information on whether both parents are carriers of the same hereditary condition.

 

…when both genetic parents are ‘carriers’ of the same autosomal recessive condition, there is a 1 in 4 (25%) chance that their child will inherit the altered gene copy from each parent, resulting in that child having the genetic diagnosis.

 

As a whole, choices about genetic screening and testing surrounding reproduction are very personal and should be made in line with one’s needs and values. Some people are empowered by the information that genetic screening and testing can provide in advance of a child’s birth, while others would prefer not to know this information in advance. There is no right or wrong answer, but careful consideration about what brings peace of mind vs. what brings anxiety may help make screening and testing decisions clearer.

 

Are there genetic chronic illnesses that are more common than others?

Yes! Some hereditary conditions are incredibly rare and may only impact a few families across the world while other conditions are very common. For example, sickle cell anemia (also called “sickle cell disease” or “hemoglobin S disease”) is an inherited, autosomal recessive condition that affects about 1 in every 365 Black American/African American babies, but the disease is possible in people of all ethnic and ancestral backgrounds. Most carrier screening panels and all newborn screening programs include testing for sickle cell anemia.

Chromosome variations that might be screened through NIPS, such as trisomy 21 (Down syndrome), are not typically hereditary, but factors like parental age may influence the likelihood of these diagnoses in a new pregnancy. Although trisomy 21 is diagnosed in about 1 in every 700 live births, this condition is more likely to be seen in the offspring of someone in their 40s compared to someone in their 20s, as the chromosomes within a human egg cell are impacted by the aging process and less likely to divide evenly prior to conception. 

 

testing kids for genetic illnesses

Source:  Gustavo Fring | Pexels

 

What should parents look for if they know there is a chance of their child having a genetic chronic illness?

Even before delivery, it’s a good idea to talk with your obstetrical care provider about whether your sonograms or lab tests may suggest a chance for a medical condition in your child. Sonograms are fine-tuned to evaluate fetal anatomy rather than chromosomes and genes that are not detectable to the naked eye. The identification of differences in your baby’s growth or development prenatally can help guide your delivery planning as well as long-term preparations for baby. After you deliver, it’s always important to talk with your child’s pediatrician about any concerns that you may have about their growth, gross and fine motor development, speech, behavior, and metabolism.

No two babies will grow and achieve milestones at exactly the same pace, but your pediatrician can help you determine whether your child’s development appears to differ when compared to their peers and/or is possibly suggestive of a genetic condition.

If you had genetic screening or testing during your pregnancy and received “negative” (normal) results, the odds are highest that your child does not have one of the conditions included on that particular screen or test. However, if you or your pediatrician is concerned that your child may be displaying signs or symptoms of a specific genetic condition, you’ll want to verify whether that condition was included on any preconception or prenatal genetic evaluation—this may help your medical provider order the right test for your child if testing is indicated! While NIPS can very reliably detect common chromosome conditions like trisomy 21, most genetic screens are limited in their ability to identify rare conditions like chromosomal microdeletions that may only impact 1 in every 25,000 people.

 

Genetic screening can be quite expensive. Is there an at-home or affordable alternative you would recommend?

Yes, the price tag of genetic screening and testing can absolutely present a major barrier for lots of parents and families in the United States! When genetic screening or testing has been recommended by a qualified medical professional, some health insurance companies may approve the testing—sometimes with and sometimes without a pre-authorization process that the health care provider needs to complete. Yet the “authorization” of genetic testing does not always guarantee that the insurance company will pay for the entire cost of testing, so it’s important to have a good understanding of the possible cost of testing before the test is initiated. 

Today, most at-home genetic tests are for recreational purposes only, although there are some important exceptions. For example, carrier screening can be performed on saliva samples as well as on blood samples, making it possible for busy parents to collect their biological specimens at home before shipping to the genetic testing laboratory. Some diagnostic genetic tests can also be performed on saliva samples collected at home, although this is usually in the context of an adult undergoing evaluation for a specific hereditary condition. Unfortunately, with most complex genetic tests, the convenience of at-home sampling does not guarantee an affordable test price. Juno Diagnostics’ prenatal genetic screens are truly unique in their ability to offer an at-home, affordable solution for parents seeking prenatal genetic information.

 

What is genetic counseling and why is it important?

The National Society of Genetic Counselors (NSGC) defines genetic counseling as “the process of helping people understand and adapt to the medical, psychological and familial implications of genetic contributions to disease.” A genetic counseling consultation will often involve reviewing one’s personal and family medical history, reviewing options for genetic testing and disease management, and counseling to promote informed choices. 

In 2022, genetic tests are more affordable and accessible than ever before. However, genetic counseling is critically important when considering whether or not to complete genetic testing and when understanding the results of a genetic test. Genetic counselors are trained experts in human genetics and psychotherapeutic counseling and are uniquely qualified to assist individuals and families in comprehensively understanding the nuances of genetic testing options and results within the context of their life and family structure(s).

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