In 1866, a British physician named John Langton Down discovered that a group of patients with intellectual disabilities had similar facial features, with wide faces and small, upturned eyes, resembling the face of the Mongolian race. This was called “Mongolian syndrome” and the first public presentation of his findings was made at a medical conference. However, the description of Mongolian disease did not reflect the essence of the disease nor was it racially discriminatory, so the naming of the disease remained inconclusive in academic circles. It was not until 1965 that the disease was named Down syndrome. It was found that people with this syndrome have one more chromosome 21 than normal (compared to two in normal people), hence the name Trisomy 21.
What are the problems of these children besides mental retardation?
In addition to the language and behavioral disorders caused by intelligence, children with Down syndrome have.
1. 40%-50% of children with Down’s syndrome have a combination of other malformations, especially congenital heart disease;
2. The risk of leukemia is 30 times higher than that of normal children;
3. Feeding difficulties, uncoordinated movements, etc;
This disease undoubtedly places a heavy burden on families.
Is there a cure for these children?
No!
How far is Down’s syndrome from my baby?
According to the “Down Syndrome Community of America” website, there is one Down syndrome fetus in every 691 births in the United States; the incidence of Down syndrome is closely related to age, with the probability of a 30-year-old pregnant woman giving birth to a child with Down syndrome being only 1 in 1000; by the age of 35, the probability is as high as 1 in 400.
What can be done to reduce the incidence of Down syndrome?
The only effective way to reduce the incidence of Down syndrome is to avoid the birth of a child with the condition. For this reason, regular maternity checkups are required for expectant mothers, and Down’s serological screening is performed in the early and middle stages of pregnancy (as shown above for trisomy 21 and trisomy 18 risk); however, since serological screening has a certain false positive rate, doctors recommend amniocentesis for high-risk patients to confirm the diagnosis.
Is amniocentesis scary and is it dangerous?
Many pregnant women become very nervous when they hear the word “puncture”, plus they have a baby inside their belly, what if the test will harm the fetus?
In fact, amniocentesis is far less mysterious and scary, and the procedure is very simple. In most cases, amniocentesis is performed in the middle of pregnancy. The pregnant woman lies flat on the examination bed, and after local sterilization and anesthesia, the doctor, under ultrasound guidance, punctures a tiny probe through the skin into the pregnant woman’s uterus and aspirates a small amount of amniotic fluid for testing. The pregnant woman needs only a small amount of cooperation during the whole process. With the continuous improvement of technology and clinical techniques, the safety of amniocentesis has been greatly improved. In the last century, the miscarriage rate was reported to be 0.5%, but in recent years it has been reported to cause only 1/1600 miscarriages.
Is there a safer way?
As early as 1997, scientists have found free DNA fragments of the fetus in the blood of pregnant women. The saying “blood is thicker than water, mother and child are connected” is not a lie from a modern scientific point of view, it is true that you have me and I have you. Since the genetic information of the child flows in the mother’s blood, it becomes feasible to learn the genetic information of the fetus by collecting the mother’s blood, and this technology is the non-invasive prenatal screening (NIPT).
Traditional serological Down’s syndrome screening is prone to false positives or false negatives (missed tests), and amniocentesis karyotyping as a confirmatory method can be traumatic to the mother. “The “non-invasive prenatal” test is a new tool to balance these two tests, improving the accuracy of the test results while ensuring no trauma to the mother. Even in the near future, with the advancement of NIPT Plus technology, non-invasive assessment of common fetal genetic disorders will be possible.
All in all, all our mothers-to-be need to know about “non-invasive prenatal” is that they only need to draw blood to screen and assess the risk of common chromosomal disorders such as Down’s syndrome in their fetus.