Down syndrome is one of the most common chromosomal abnormalities in live births. On average, one child per 700 newborns is born with this syndrome. Despite its frequency, most people don’t know much about Down syndrome, so they form their opinion on outdated prejudices that shows people with the syndrome in a bad light. Today, Down syndrome does not mean the same fate or future as it did decades ago.
We remember from basic biology lessons that people have 23 pairs of chromosomes present in each body cell, a total of 46 chromosomes. We received 23 from our mother and 23 from our father. Each of those chromosomes carries a complex genetic record that determines our traits and functioning of our bodies. However, people with Down syndrome have an additional copy of chromosome 21. Because they carry tree chromosomes 21, this condition is also called trisomy 21.
“Syndrome” means a set of physical and mental symptoms (or characteristics) that continuously appear together, in this case, in the presence of a third copy of chromosome 21. The name “Down” comes from doctor Langdon Down, who first described these characteristics. The additional chromosome that causes Down syndrome was discovered in 1959. The development of genetics helped us understand trisomies much better.
The frequency of Down syndrome is 1 in 700
People with Down syndrome usually have distinctive facial features, low muscle tone, lower stature, and stocky physique. Their mental and physical development is slower. But these common characteristics do not mean that all people with Down syndrome are the same and will have equal development. Down syndrome varies in its intensity. About half of babies with Down syndrome experience heart defects, but modern medicine can treat them.
We know much more about Down syndrome today than we used to, which makes it easier for us to understand and live with this condition. As a result, the life span of people with the syndrome has changed significantly. Back in 1982, the average life expectancy of people with Down syndrome was only 25 years, mostly spent in psychiatric institutions. Today, people with this syndrome live on average for 60 years, and their lives are much fuller.
What causes Down syndrome?
Trisomy 21 happens because to an error in cell division during meiosis. The causes of it are still unclear to this day and can occur in any pregnancy. But the fact is that the chance of Down syndrome increases with the age of the pregnant woman.
For example, the risk of having an additional copy of the 21st chromosome is 1 in 1,150 when women are 21 years old. While for 36-year-old women, the risk increases in 1 in 210 and women at 42 have 1 in 40 chance. There is also a 30% chance of miscarriage if you are carrying a child with this kind of genetics mistake.
Risk of Down syndrome in live births (%)
Is It possible to detect Down syndrome before the baby is born?
Yes, trisomy 21 can be detected before birth. Because today we have a lot of information available on the syndrome it is important to identify its presence as soon as possible. The unexpected birth of a child with Down syndrome is a massive shock to the parents. Fortunately, Down syndrome can be detected today with prenatal tests that analyse potential presence of chromosomal abnormalities.
We can discover Down syndrome in the fetus with non-invasive prenatal tests, such as nuchal translucency scan and NIPT test. As early as from week ten of pregnancy, the Prenascan by GenePlanet test detects this type of genetic defect with 99% accuracy. For final confirmation, however, gynaecologists and physicians use invasive methods like amniocentesis and chorionic villus sampling.
The discovery of Down syndrome at an early stage of pregnancy allows parents to learn more about the syndrome and talk to doctors, experts, and parents who have children with Down syndrome. This way, they can create a realistic picture of living with the syndrome, gather knowledge, and prepare for the future even before the baby’s born.
Living with Down syndrome
Each person has their character, talents, and abilities. This also applies to people with Down syndrome. Although children with trisomy 21 have some common characteristics, they are very distinctive and unique.
In the past, people with the syndrome have been underestimated and misunderstood. It has led to strong prejudice, portraying them as entirely incompetent, helpless, and condemned to life in institutions. That is, of course, not the case. Today they live significantly better than they used to, as society provides parents with much more support, therapies, and information about appropriate care and education.
Most children with Down syndrome learn to walk and talk. Most know the basics of reading and computation. Some go to mainstream elementary schools; others attend tailored programmes. They have friends, hobbies, and later even jobs. Nowadays, in more advanced societies, people with Down syndrome also have more opportunities to work and can grow into semi-independent individuals. Some even get married and get a driver’s license.
If people with a “normal” chromosome count often feel superior compared to people with Down syndrome, at least in one area they should not: emotional intelligence. People with trisomy 21 have much more developed emotional intelligence. They have, in the absence of perceptual and speech abilities, emotional experience in abundance. They are deeply compassionate, eager to help, and kind.
Many parents will tell you that a child with Down syndrome has changed their life’s outlook and taught them a lot of positive things. Some say that the extra chromosome may slow the development, but it makes it up for with love and joy.
But that doesn’t change the fact that discovering Down syndrome in a child is very stressful for parents. They can experience a range of emotions and can feel scared and lost. At such times, parents can turn to institutions for help, consult doctors, or contact parents who have personal experience. The realisation that they are not alone in this is of paramount importance.