Personalities

Ekaterina N. Tolmacheva

Tamara P. Vetlugina, PhD, Researcher, Laboratory of Cytogenetics, Institute of Medical Genetics, Tomsk NRMC.

Contact details

e-mail: e-mail: kate.tolmacheva@medgenetics.ru
Phone: 8 (3822) 51-31-46
fax: 8 (3822) 51-37-44

Brief Biography

In 1985 she graduated from the Tomsk State University, biology and soil faculty. From 1988 to the present, he has been working in the cytogenetics laboratory, first as a senior laboratory technician and then as a researchert. In 2001 she defended her thesis for the degree of candidate of biological sciences in the specialty "genetics".

Research Interests

The scientific activities of Tolmacheva E.N. are concentrated in the field of the study of epigenetic modifications of the genome in cases of human embryoletality. For the first time, the methylation profile of two placental tissues — the extra-embryonic mesoderm and cytotrophoblast in the normal embryo of the first trimester of pregnancy, was revealed using the Infinium HumanMethylation27 BeadChip (Illumina, United States) microarray. Next, a comparative characteristics of the DNA methylation profile of placental tissues of embryos with a normal karyotype and trisomy of chromosome 16 was carried out. It was established that there are multiple differences between extra-embryonic tissues with normal and aneuploid karyotype (Tolmacheva et al., 2011) Moreover, the analysis of the DNA methylation index of retrotransposon LINE-1 in the placental tissues of embryos with normal and aneuploid karyotype showed that placental tissues of spontaneous abortions with chromosomal mosaicism are characterized by the maximum LINE-1 methylation index among all studied groups. At the same time, excessive hypomethylation of the mobile genetic element was recorded in miscarriage with a normal karyotype. It is hypothesized that impaired demethylation of the parental genomes during epigenetic reprogramming at preimplantation stages of development may be associated with an increase in the error rate of mitotic segregation of chromosomes leading to the formation of a mosaic karyotype (Vasiliev et al., 2015). In addition, she studies the inactivation of the X chromosome in various disorders of embryogenesis and in women with miscarriage. It was found that spontaneous abortions, characterized by the absence of a developed embryo, as well as those obtained from couples with recurrent miscarriages, are characterized by a high frequency of skewed inactivation of the X chromosome. Deviations towards primary inactivation of one of the parental homologs may indicate the presence of X-linked mutations that affect the viability of the embryo (Tolmacheva et al., 2015).

Main Publications

1. Tolmacheva E.N., Kashevarova A.A., Sukhanova N.N., Kharkov V.N., Lebedev I.N. Skewed X-chromosome inactivation in human embryos with mosaic trisomy 16 // Russian Journal of Genetics. 2011. V. 47. № 3. P. 354-357.


2. Kashevarova A.A., Tolmacheva E.N., Sazhenova E.A., Sukhanova N.N., Lebedev I.N. Epigenetic status of cell cycle regulation genes in the placenta of human embryos with chromosomal mosaicism // Molecular Biology. 2011. V. 45. № 2. P. 283-290.


3. Тolmacheva E.N., Kashevarova A.A., Skryabin N.A., Lebedev I.N. DNA methylation profile in human placental tissues // Molecular Biology. 2011. V. 45. № 3. P. 493-499.


4. Skriabin N. A., Lebedev I.N., Tolmachëva E.N., Vtorushin S.V., Slonimskaia E.M., Cherbyntseva N.V. Epigenetic aspects of early lymphogenic metastasis in breast cancer// Vopr Onkol. 2011. V. 57. №. 6. P. 717-21.


5. Skryabin N.A., Tolmacheva E.N., Lebedev I.N., Zavyalova M.V., Slonimskaya E.M., Cherdyntseva N.V. Dynamics of aberrant methylation of functional groups of genes in progression of breast cancer // Molecular Biology. 2013. V. 47. № 2. P. 267-274.


6. Kashevarova A.A., Nazarenko L.P., Skryabin N.A., Salyukova O.A., Chechetkina N.N., Tolmacheva E.N., Sazhenova E.A., Magini P., Graziano C., Romeo G., Kučinskas V., Lebedev I.N. Array CGH analysis of a cohort of Russian patients with intellectual disability // Gene. 2014. V. 536. № 1. P. 145-150.


7. Tolmacheva E.N., Kashevarova A.A., Skryabin N.A., Lebedev I.N. Epigenetic effects of trisomy 16 in human placenta // Molecular Biology. 2013. V. 47. № 3. P. 373-381.


8. Kashevarova A. A., Skryabin N.A., Cheremnykh A.D., Tolmacheva E.N., Sazhenova E.A., Salyukova O.A., Chechetkina N.N., Didenko L.I., Sukhanova N.N., Yakovleva Y.S., Torkhova N.B., Nazarenko L.P., Magini .P, Graziano C., Romeo G., Lebedev I.N. Clinical and genetic analysis of idiopathic intellectual disability based on array comparative genomic hybridization //Zh Nevrol Psikhiatr Im S S Korsakova. 2013. V. 113. № 9. P. 70-74.


9. Vasilyev S.A. , Tolmacheva E.N., Kashevarova A.A., Sazhenova E.A., Lebedev I.N. Methylation status of LINE-1 retrotransposon in chromosomal mosaicism during early stages of human embryonic development // Molecular Biology. 2015. V 49. № 1. P. 144-152.


10. Tolmacheva E.N., Vasilyev S.A., Sazhenova E.A., Zhigalina D.I., Grigorovich E.I., Nikitina T.V., Melnikov A.A., Zhabina E.S., Ivanova T.V., Evtushenko I.D., Lebedev I.N. Skewed X-chromosome inactivation in human miscarriages // Tsitologiia. 2015. V.57. №.11. P. 808-12.