Scientists from the laboratory of cytogenetics of the Research Institute of Medical Genetics of the Tomsk NRMC investigated how the presence of an extra chromosome 16 in the cells of the embryonic part of the placenta affects the regulation of the activity of more than 14 thousand genes.
The results of the study are published in Scientific Reports.
- The study was conducted with the support of the RSF grant No. 19-74-10026
Each cell of the human body contains 23 pairs of chromosomes. An abnormal number of individual chromosomes leads to disorders of the development and functioning of the body, for example, Down syndrome, when cells contain an extra chromosome 21. The wrong number of other chromosomes also leads to severe hereditary diseases (for example, chromosomes 13, 18, X, and Y).
The presence of an extra chromosome 16 (trisomy 16) most often leads to spontaneous pregnancy loss in the first trimester. Sometimes trisomy 16 occurs only in the embryonic part of the placenta, and the fetal cells contain a normal number of chromosomes – in this case, the child can be born healthy. Understanding the consequences of trisomy 16 is necessary for doctors to identify potential dangers to the fetus and mother during pregnancy.
Scientists of the Tomsk NRMC found out that one of the basic mechanisms of genome regulation, DNA methylation, is abnormal in cells with an extra chromosome 16.
"Abnormal DNA methylation in placental cells pathologically changes the regulation of the genes responsible for the development of the embryonic part of the placenta and the interaction of the embryo and the mother. As a result, the embryo may not receive enough nutrients and develops with delays. Impaired release of signaling molecules by the embryo can lead to the development of pathological changes in the mother's body (for example, pre-eclampsia)", says Stanislav Vasilyev, Doctor of Biological Sciences, head of the laboratory of cytogenetics of the Research Institute of Medical Genetics of the Tomsk NRMC.
Further studies of disorders in trisomy 16 will help to understand better the mechanisms of interaction between the placenta and the mother's body that are the most critical for the normal growth and development of the embryo.
Diagnosis of cytogenetic causes of miscarriage is traditionally carried out in the Research Institute of Medical Genetics Clinic of the Tomsk NRMC, where married couples with such a problem can apply, get the results of diagnostic tests and advice from a geneticist.