Patau Syndrome - what awaits future parents?

Congenital diseases that are associated with a violation of the number of chromosomes storing hereditary information are found in about 1% of newborns, while about 20% of spontaneous early miscarriages are due to an abnormal set of chromosomes in embryos. The Patau syndrome is one of the chromosomal pathologies incompatible with normal life.

Patau Syndrome - what is this disease?

The Patau syndrome is characterized by the presence in the cells of the additional chromosome number thirteen, i.e. Instead of a pair of homologous chromosomes of this type, there are three such structures. Anomaly is also defined by the term "trisomy 13". Normally, the set of chromosomes in the cells of the human body (normal karyotype) is represented by 46 elements (23 pairs), of which two pairs are responsible for sexual characteristics. When studying a karyotype in blood cells, changes in the structure of chromosomes that do not affect his health can be revealed in any person, but capable of making themselves felt in descendants.

Patau Syndrome - the type of inheritance

When diagnosed as "Patau syndrome", the karyotype is expressed by a formula of this type: 47 XX (XY) 13+. In this case, three copies of the thirteenth chromosome can be present in all cells of the body, in other cases an additional synthesized chromosome is found only in some cells. This happens due to an error in the division of cells at the beginning of the development of the embryo after the connection of the egg and sperm, which occurs under the influence of any internal or external influences. Moreover, an extra chromosome can come from both the mother and the father, who do not have genetic deviations.

In addition, there are cases where an additional chromosome number 13 can be attached to another chromosome in an egg or sperm cell, which is called translocation. This is the only form of the Patau syndrome that can be transmitted from one of the parents. People who are carriers of altered genetic material and who do not show signs of disease can transmit it to children who are born ill.

Risk of trisomy 13

The Patau syndrome in a fetus is often a bitter accident, from which no one is immune. Recently, many couples are recommended to perform karyotyping before conception planning, even if the high risk of Patau syndrome or other chromosomal abnormalities is not established. This technique studies the set of chromosomes of a woman and a man, reveals various deviations. At a minimum, due to the study of the genome of parents, it is possible to predict whether there is a probability of an hereditary form of pathology.

Like many other chromosomal abnormalities, the disease under consideration in most cases occurs in children conceived by women older than 35-45 years. Therefore, early in pregnancy is prescribed if there is a high risk of the Patau syndrome, amniocentesis is the study of fetal cells for the presence of genetic defects. Such an analysis is carried out by means of a puncture puncture of the uterine cavity and collection of amniotic fluid with the presence of lean cells of the fetus.

Patau syndrome - frequency of occurrence

The karyotype, characteristic of the Patau syndrome, is recorded approximately once for every 7-14 thousand newborns born alive. The occurrence in boys and girls is the same. In addition, pregnancies with such a deviation in the fetus belong to the group at high risk of miscarriage or stillbirth. In 75% of cases, the parents of children with this diagnosis do not have chromosomal abnormalities, the remaining episodes are associated with a hereditary factor - due to the transfer of the translocalized chromosome number 13 from one of the parents.

Patau Syndrome - the causes of

Non-hereditary forms of the disease do not yet have clear causes of the onset, the study of provoking factors requires complex research. To date, it has not even been established exactly at what point a failure occurs - when forming the sex cells or when forming a zygote. It is believed that further chromosome makes it difficult to read the genome by cells, which becomes an obstacle to the normal formation of tissues, the successful and timely completion of their growth and development.

Scientists suggest that the cause of the Patau syndrome can be associated with such factors:

Patau syndrome - signs

In some cases, when not only the number of cells in the body is affected, not very pronounced and not rapidly developing anomalies are observed, but often deviations are significant. Moreover, in addition to external defects that can be seen in the photo, the Patau syndrome is characterized by a number of malformations of internal organs. Most deviations are irreversible.

Let's enumerate what the symptoms of Patau's syndrome are:

1. Associated with the nervous system:

2. Musculoskeletal, skin abnormalities:

3. Urogenital symptoms:

4. Other anomalies:

Patau's syndrome - diagnostic methods

After the birth of a child, the diagnosis of Patau's syndrome does not present any difficulties by visual inspection. To confirm the diagnosis, a blood test is performed to detect the genotype of the Patau syndrome, ultrasound. Genetic analysis is also carried out in cases of infant death, which makes it possible to find out the form of the disease, to understand whether it is hereditary (important for further planning of children).

Syndrome Patau - tests

It is much more important to determine in a timely manner a deviation in the early stage of pregnancy, which can be done approximately at the end of the first trimester. Before the birth of Trisomy 13 chromosome can be detected by examining cells from the amniotic fluid (amniotic fluid) obtained during the amniocentesis or from cells obtained by chorion biopsy.

Prenatal analysis can be carried out when parents are at risk of developing a hereditary pathology and in screening the hereditary information of the pregnant fetuses. At different times, such methods of sampling material are used for the purpose of analyzing the quantitative fluorescent polymerase chain reaction method:

Syndrome Patau on ultrasound

Starting with the twelfth week of pregnancy, developmental defects in the fetus can be detected by ultrasound diagnosis. Patau's syndrome is characterized by the presence of the following symptoms:

Treatment of the Patau syndrome

Regrettably, this may sound, but children with Patau syndrome are terminally ill, because they are not sick. it is impossible to correct chromosomal abnormalities. Syndrome Patau means a deep degree of idiocy, complete disability. Parents who have decided to give birth to a baby with such abnormalities should be determined that he will need constant care and treatment. Surgical interventions and drug therapy can be performed to correct the functioning of vital systems and organs, plastic surgery, the prevention of infections and inflammations.

Patau's syndrome - prognosis

For children diagnosed with Patau's syndrome, life expectancy in most cases does not exceed one year. Often such babies are doomed to death in the first weeks or months after birth. Less than 15% of children live to the age of five, and in developed countries with a high level of the health care system, about 2% of patients survive to ten years. In this case, even those patients who do not have large-scale organ damage, are not able to adapt themselves and take care of themselves.