Prenatal And Postnatal DNA Tests

What to do expectant Mothers, to take precautions in Pregnancy and to avoid Miscarriages

The pregnancy process covers three separate periods: formation, development and growth. Life that begins as a cell in the mother’s womb turns into one hundred trillion cells and two hundred and sixteen organs. Therefore, the first three months are the formation month, it is in the form of a clot, and coagulation disorders are very important for the mother and the baby. The second trimester is the development of the organs, while the organs develop, the development continues within the genetic structures that pass from the mother and father, the last three months are the growth period of the organs, in this period, besides the genetic structure of the mother and father, environmental factors are very important.

Determining the cause of miscarriage during pregnancy requires long and costly studies. Especially in the process of determining the factor that causes past miscarriages, because of the lack of fetal material, studies are mostly limited to maternal and paternal analyzes and diagnostic success decreases.

Incidence: The incidence of spontaneous miscarriage is 1% in pregnant women, and 60-70% live births occur in women who do not receive treatment for spontaneous abortion. Maternal age and pregnancy history are independent and important risk factors. Risk of miscarriage; 1. 15% after abortion 2. 24% after abortion, 3. It gradually increases with a frequency of 30% after abortion, 40-50% after abortion.

It is known that maternal age is an important factor. The data obtained can reach 75-80% of the low risk, which starts to increase after the age of 25, in women over the age of 45.

• Genetic Factors
• Chromosome Diseases
• Single Gene Diseases
• Hereditary Thrombophilia (vascular occlusion)
• Endocrine factors
• Autoimmune factors
• Anatomical factors
• Infections
• Miscarriages of unknown cause

Genetic Factors

Chromosomal Diseases

1.Chromosomal abnormalities in fetus or abortion material:

More than 80% of pregnancy losses occur in the first trimester and chromosome anomaly is detected in 53% of these cases. In order to investigate fetal anomalies that cause recurrent miscarriages, chromosome analyzes are performed from abortion material, chorionic villi, amniotic fluid and cord blood

2.Chromosomes anomalies in spouses:

The frequency of detecting chromosomal anomalies in spouses with a history of recurrent pregnancy losses has been reported to be 3-10%

Single Gene Diseases

Among single gene diseases such as cystic fibrosis, thalassemia and sickle cell anemia, it can lead to recurrent pregnancy losses, especially in individuals with a family history. Family history, physical examination, pathological examination, genetic studies in the fetus and parents are of great importance in the diagnosis of single gene diseases. A detailed family tree should be created and genetic counseling should be given.

Hereditary Thrombophilia (vascular occlusion)

In families with recurrent pregnancy losses, the incidence of thrombophilia can rise up to 60%. Placental vascular occlusion due to hereditary and / or acquired thrombophilic disorders significantly increases the risk of recurrent pregnancy losses and pregnancy complications.

Factor II (PTH) G20210A, Factor V G1691A, Factor V H1299R, Factor XIII V34L, MTHFR C677T, MTHFR A1298C, PAI-1 (4G / 5G), EPCR A4600G (A3), EPCR G4678C (A1) are the main genes used to determine susceptibility to thrombosis.

Genetic Disease Screening in Postpartum Infants

Studies in the field of genetics continue to progress rapidly with innovations every day. In recent years, a success rate of 90% has been achieved in the diagnosis of all diseases by screening 200,000 exomes and 21,000 genes with all exome analysis and whole genome analysis. In addition, by working on the mitochondrial genes that provide the energy of the cell, the diagnosis of diseases has become clearer.

Another innovation is the start of detailed genetic screening in babies between 0-24 months. With Newborn Screening Program conducted across the whole of Turkey by the Ministry of Health, all of newborns with congenital hypothyroidism were only three major disease, phenylketonuria and biotinidase deficiency in terms of screening is done. Apart from the tests applied by the Ministry of Health, we recommend the newborn genetic screening test for babies aged 0-24 months, which is related to the most known diseases.

350 million children in the world have different genetic diseases, 80% of them are composed of rare genetic diseases. Thanks to the human genome project and daily new researches, 4300 genetic diseases can now be diagnosed among these diseases. 32% – 57% of newborn babies are affected by genetic diseases but it is not recognized as there is no apparent significant anomaly.

For example, in some cases, the mother and father are healthy, they do not have any problems, they do not have the knowledge of the past period, whether there are hereditary diseases in the family, they have a healthy child and the tests performed by the Ministry of Health are found to be normal. However, in the future, our child is also worried about a health problem, because some families also see this, the child becomes ill at the age of two to three, can be lost due to rapidly progressing diseases, or he can continue his life with severe mental disability. In order to reduce the possibility of these samples, it is of great importance to make Postnatal Genetic Screening Tests more widespread and to be performed by the parents.

Which Diseases Are Covered In The New Born Genetic Screening Test?

Organic Acidemias

Fatty Acid Disorders

Amino Acid Disorders

Immune Deficiencies

Mucopolisaaccharidoses

Glycogen Storage Diseases

In Which Situations Should Neonatal Screening Tests Be Done?

Problems in laboratory parameters:

a. Hyperbilirubinaemia

b. Hypoglycemia

c. Lactic acidosis

Skeletal abnormalities

a. Recurrent fractures

b. Microcephaly

Neurological abnormalities

a. Convulsions

b. Spasisite

c. Muscular hypotonia

d. Dystonias

Hematological abnormalities

a. Anemia

b. Immunodeficiency

Skin abnormalities

a. Ichthyosis

Gastrointestinal abnormalities

a. Hepatomegaly

b. Cholelithiasis

c. Diares

d. Anal Atresia

In our Center, the Neonatal Screening Panel uses the Next Generation Sequencing Analysis method and a panel called CentoICU, which examines approximately 800 genes. In addition, the diagnosis of newborn patients can be made quickly with methods such as Whole Genome Analysis (WGS) & Whole Exome Analysis (WES).

Patients applying to our center; A detailed report containing detailed clinical information, all previous tests and family tree is prepared, after giving detailed information about the tests, the consent documents are signed, and then all the information is entered into the CENTOPORTAL system by processing the blood samples taken on special cards. The samples taken are shipped to Germany on the same day with special cards.

After the results are obtained, detailed interpretation of the results is made and genetic counseling is given. In addition, after discussing the clinical and molecular aspects of the patient, the patient’s diagnosis becomes clear and the treatment method is determined more clearly by the physician.