Down Syndrome: Causes, Symptoms, and Treatment
Medically reviewed by Sumiran Racherla, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Down Syndrome?
A pediatrician, a doctor for children, or a primary care doctor usually gives regular care for Down syndrome. A clinical geneticist, a doctor who treats inherited conditions, may also help. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is Down syndrome?
Down syndrome is a condition in which a person has an extra copy of chromosome 21. Chromosomes are small packages of genes in the body's cells. The extra chromosome changes how the body and brain develop. It can cause both physical and mental challenges.
Each person with Down syndrome has different abilities. Another name for it is trisomy 21. It is the most common chromosomal condition diagnosed in the United States.
Symptoms
The symptoms are different in each person. People usually have mild to moderate intellectual disabilities. Development is often delayed. For example, they may start talking later than other children.
Common physical signs include:
- A flat face.
- Eyes that slant up.
- A short neck.
- Small hands and feet.
- A single line across the palm of the hand.
- Poor muscle tone or loose joints.
Behavior problems can include attention problems and stubbornness or tantrums.
Many people with Down syndrome have healthy lives. But some have birth defects or other health problems, such as:
- Heart defects that are present at birth. About half of babies with Down syndrome are born with one.
- Hearing loss.
- Ear infections.
- Eye diseases.
- Sleep apnea, a disorder that makes you repeatedly stop breathing during sleep.
- Digestive problems.
- An underactive thyroid gland, which affects about 15 percent of people with Down syndrome.
Causes and who gets it
Most cases come from trisomy 21. Each cell in the body then has three copies of chromosome 21 instead of the usual two. There are three types of Down syndrome.
- Trisomy 21 is the most common type. About 95% of people with Down syndrome have it.
- In translocation Down syndrome, an extra part or a whole extra chromosome 21 is attached to a different chromosome. This type accounts for about 3% of people with Down syndrome.
- In mosaic Down syndrome, some cells have three copies of chromosome 21 and other cells have the usual two. This type accounts for about 2% of people with Down syndrome.
Down syndrome is usually not inherited. It happens by chance, as an error when cells divide early in the baby's development. Translocation Down syndrome can be passed down from a parent who carries a rearrangement of genetic material.
Doctors do not know for sure why it happens. The risk of having a baby with Down syndrome goes up with the mother's age, especially at 35 or older. Still, most babies with Down syndrome are born to mothers younger than 35, because younger women have many more births. Parents who have one child with Down syndrome have a higher chance of having another.
How doctors diagnose it
Providers can check for Down syndrome during pregnancy or after a child is born.
Prenatal screening tests show whether an unborn baby has a higher or lower chance of Down syndrome. Screening tests do not give a firm diagnosis. Prenatal diagnostic tests check the chromosomes in a sample of cells. They can diagnose or rule out Down syndrome. These tests have a small risk of causing a miscarriage.
After birth, a provider may make an initial diagnosis from the baby's physical signs. A karyotype test can confirm it. It checks a sample of the baby's blood for extra chromosomes.
Treatment
There is no single, standard treatment for Down syndrome. Treatment is based on each person's physical and intellectual needs, strengths, and limitations.
Early services help children grow to their full potential. They include speech, occupational, and physical therapies. Early intervention programs in each state usually offer them. Children may also need extra help in school, though many are included in regular classes.
People with Down syndrome need regular medical care. They may need extra health screenings to check for problems that happen more often in Down syndrome. People with Down syndrome can lead healthy lives with supportive care.
When to see a doctor
If a screening test in pregnancy shows a baby could have Down syndrome, you need another test to find out for sure.
People with Down syndrome need regular medical care, so keep up with checkups and extra screenings.
Call 911 or go to the emergency room for severe trouble breathing, chest pain, fainting, or a sudden change in mental state.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. A direct primary care doctor can handle routine checkups and screenings. They can also help you keep track of visits with specialists and therapy services.
Common questions
Is Down syndrome inherited?
No, most cases of Down syndrome are not inherited. Translocation Down syndrome can be passed down from a parent who carries a rearrangement of genetic material.
Can people with Down syndrome live healthy lives?
Yes, people with Down syndrome can lead healthy lives with supportive care. They will need regular medical care.
Can Down syndrome be found before birth?
Yes, providers can check for Down syndrome during pregnancy. Screening tests show a higher or lower chance. Diagnostic tests can diagnose or rule out Down syndrome.
Do all people with Down syndrome have the same abilities?
No, each person has different abilities. The symptoms are different in each person.
Sources
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
