What is the reason for the birth of children with Down syndrome

Today there is a lot of information about such a genetic disease like Down Syndrome. Despite this, many parents put a cross on their children, often refuse, believing that it is impossible to live with this pathology. However, this is not the case. And it is also very important to understand for what reason the syndrome develops and how to diagnose it at the earlier stage.

The main causes of down syndrome

This is a genetic disease that occurs in the fetus at the time of conception, that is, when a sperm and egg cell merge. In 85% of cases, this is due to the fact that the female sex cells carry a set of not 24 chromosomes, but 24. In other cases, extra chromosomes are transmitted from the father.

Thus, unhealthy diet, problem birth, stress, bad habits - do not lead to the appearance of Down syndrome.

Blame special protein, which leads to the appearance of an extra chromosome. Its main function is cell stretching during division, which allows each of the daughter cells to receive one chromosome from a pair. If the protein has a defect, as a result, not 23 chromosomes are formed, but 24, which causes this genetic pathology.

The mechanism of disruption of the development of the central nervous system in this pathology is associated with the "extra" 21 chromosome, which causes the peculiarities of its development. These deviations underlie the delay of fetal development: mental and mental:

1. Disturbances in the circulation of cerebrospinal fluid, which accumulates in the ventricles of the brain. This causes intracranial pressure.
2. Focal brain damage, nerves. This leads to inhibition of motor development, the appearance of problems with movement, coordination.
3. Cerebellum - small, which affects the lack of performance of its functions. This manifests itself in a weakened muscle tone; a person cannot control his body.
4. Disorders in the cerebral circulation, which is associated with unstable work of the cervical spine, weakness of the ligaments, which causes pinching of blood vessels.
5. The number of nerve impulses decreases, which leads to a decrease in the speed of thought processes, manifested by lethargy.

What factors and pathologies increase the risk of developing the disease?

Despite the fact that Down syndrome is an exclusively genetic pathology, there are factors that increase the risk of its development in the fetus.

These include:

1. Marriages between close relatives, since they are carriers of the same pathologies. Therefore, if two people have protein defects, 21 chromosomes, then the likelihood of Down syndrome is very high. And the closer the degree of kinship, the higher the likelihood of this pathology.
2. Early pregnancies, since the female body is not yet fully formed, the sex glands can malfunction. All this can cause genetic abnormalities in the child.
3. Mother's age is over 35 years. Throughout life, a woman's body is affected by various factors, including negative ones. For this reason, deciding to have a child aged 35 years, the expectant mother is required to undergo consultation with geneticists, which will determine the possible pathology of the child. A similar problem applies to men over 45 years.

To date, there is one program that can calculate the risk of developing a fetus with Down syndrome. It takes into account such factors as:

• parents' age, their ethnicity;
• gestational age;
• body weight;
• chronic diseases and pathologies.

Diagnosis of a genetic disease during pregnancy

The first thing that doctors prescribe for diagnosis is the delivery of a blood test to determine the karyotype. Due to the results obtained, you can see the total set of chromosomes in parents. Abnormal is the karyotype with 21 chromosomes.

It can also show the problem and the passed ultrasound diagnosis in 1 trimester. The specialist must check the thickness of the collar space of the fetus: if this figure is more than 2.5 mm, then there is a high risk of having Down syndrome.

Used and biochemical tests that are carried out at 10 weeks of pregnancy. Analyzes can determine the level of chorionic hormone, also studied plasma protein A in the blood of a pregnant woman. At week 16, a triple alpha-fetoprotein and estriol test is prescribed.

If during the ultrasound and biochemistry, the doctor finds a suspicion of this pathology, the patient can be recorded for chorionic biopsy, which will help to study the shell of the fetus.

Methods for identifying Down syndrome include:

• amniocentesis, for which a woman's amniotic fluid test is prescribed;
• antenna diagnostics helps to determine venous blood parameters;
• Ultrasound to determine the collar area;
• general study of protein A;
• conducting a triple test.

The most effective diagnostic methods are chorionic biopsy and amniocentesis, however they carry a certain risk for both the mother and the fetus.

The main signs of Down syndrome in a child and an adult

There are a number of major signs of this genetic disease in newborns, older children and adults. Moreover, more than 80% of children with this syndrome are similar to each other, but very different from their parents.

Speaking of infants, it is worth noting the following:

• weight and height below average - average weight up to 3 kg, height - about 45 cm;
• a short head, and a section of the skull where the brain is located, has a small longitudinal but wide transverse diameter;
• the presence of a third fontanel;
• in almost 75% of these children, the cap has a flat shape;
• 80% of children have a mongoloid cut in their eyes, and squint often occurs;
• pigment spots with a diameter of up to 1.5 mm are observed on the iris;
• the neck is wide, short, it has a deep fold;
• the tongue is large, in 50% of cases it does not completely fit in the mouth;
• in 40% of children, the nose is very short, and the nose bridge is pressed into the forehead;
• the jaws are small, the sky is "gothic";
• the mouth is usually open, which is caused by a decrease in the tone of the muscles that cover the jaw;
• auricles are small, modified, asymmetrical, may be soft;
• compared to body length, limbs are very shortened in more than 60% of newborns;
• palms in children are short, wide, little fingers are usually twisted.

However, in 10% of newborns with such a problem, these symptoms may be mild. And much of the above, on the contrary, is also present in healthy children. Therefore, it is impossible to diagnose Down Syndrome on the basis of only visual factors — only a genetic analysis can prove this.

What can be complications?

Due to the nature of the development, genetic abnormalities and pathologies, Down syndrome can cause a number of serious complications:

1. Heart disease. More than 50% of children who suffer from this pathology are born with congenital heart disease. This may require surgery in children.
2. Leukemia. Small children born with this diagnosis are much more likely to suffer from this disease than healthy ones.
3. Infectious diseases. As a result of having an extra chromosome, people with Down syndrome are very susceptible to infectious diseases due to a compromised immune system.
4. Dementia. Such a problem is most often faced by adults with Down syndrome. Moreover, the symptoms of this disease usually "wake up" by the age of 40 - that is, they occur earlier than in healthy people.
5. Obesity. The percentage of obese patients in children with this syndrome is much higher than in healthy people.

What should parents of children with Down syndrome know?

Many parents, upon learning about the diagnosis, get scared. Some abandon children. However, it is worth remembering that with proper care, the provision of medical care, such children are often in intelligence and mental development will not be different from healthy.

Features:

1. Despite the presence of developmental delay, these children can be trained. With the use of special programs, their IQ can be increased to 75. With the right approach, continuous development, some of the children even get higher education, get a job.
2. Child development will be faster if surrounded by healthy people, raised in a family, and not in specialized boarding schools.
3. Children with this syndrome are more open, kind, very friendly. They sincerely fall in love, create families. True, the risk of hereditary disease in such pairs is 40%.
4. With constant medical care, care, people with such a diagnosis can live up to 50 years or more.

Watch the video: The Truth About Down Syndrome (May 2024).