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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">medgen</journal-id><journal-title-group><journal-title xml:lang="ru">Медицинская генетика</journal-title><trans-title-group xml:lang="en"><trans-title>Medical Genetics</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2073-7998</issn><publisher><publisher-name>Publishing House «Genius Media» LLC</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.25557/2073-7998.2024.10.50-54</article-id><article-id custom-type="elpub" pub-id-type="custom">medgen-2563</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>КРАТКОЕ СООБЩЕНИЕ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>BRIEF REPORT</subject></subj-group></article-categories><title-group><article-title>Уровень метилирования ретротранспозона LINE-1 в ворсинах хориона в эмбрионах  из семей со спорадическим и привычным невынашиванием беременности</article-title><trans-title-group xml:lang="en"><trans-title>The level of methylation of LINE-1 retrotransposon in chorionic villi  in embryos from families with sporadic and recurrent miscarriage</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Деменева</surname><given-names>В. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Demeneva</surname><given-names>V. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>634050, г. Томск,  ул. Набережная реки Ушайки, д. 10</p></bio><bio xml:lang="en"><p>10, Naberejnaya Ushaiki, Tomsk, 634050</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Толмачева</surname><given-names>Е. Н.</given-names></name><name name-style="western" xml:lang="en"><surname>Tolmacheva</surname><given-names>E. N.</given-names></name></name-alternatives><bio xml:lang="ru"><p>634050, г. Томск,  ул. Набережная реки Ушайки, д. 10</p></bio><bio xml:lang="en"><p>10, Naberejnaya Ushaiki, Tomsk, 634050</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Филатова</surname><given-names>С. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Filatova</surname><given-names>S. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>634050, г. Томск,  ул. Набережная реки Ушайки, д. 10</p><p> 634050, г. Томск,  пр. Ленина, д. 36</p></bio><bio xml:lang="en"><p>10, Naberejnaya Ushaiki, Tomsk, 634050</p><p>36, Lenin Avenue, Tomsk, 634050</p></bio><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Зуев</surname><given-names>А. С.</given-names></name><name name-style="western" xml:lang="en"><surname>Zuev</surname><given-names>A. S.</given-names></name></name-alternatives><bio xml:lang="ru"><p>634050, г. Томск,  ул. Набережная реки Ушайки, д. 10</p></bio><bio xml:lang="en"><p>10, Naberejnaya Ushaiki, Tomsk, 634050</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Ушакова</surname><given-names>А. С.</given-names></name><name name-style="western" xml:lang="en"><surname>Ushakova</surname><given-names>A. S.</given-names></name></name-alternatives><bio xml:lang="ru"><p>634050, г. Томск,  ул. Набережная реки Ушайки, д. 10</p><p> 634050, г. Томск, пр. Ленина, д. 36</p></bio><bio xml:lang="en"><p>10, Naberejnaya Ushaiki, Tomsk, 634050</p><p>36, Lenin Avenue, Tomsk, 634050</p></bio><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Васильева</surname><given-names>О. Ю.</given-names></name><name name-style="western" xml:lang="en"><surname>Vasilyeva</surname><given-names>O. Yu.</given-names></name></name-alternatives><bio xml:lang="ru"><p>634050, г. Томск,  ул. Набережная реки Ушайки, д. 10</p></bio><bio xml:lang="en"><p>10, Naberejnaya Ushaiki, Tomsk, 634050</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Саженова</surname><given-names>Е. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Sazhenova</surname><given-names>E. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>634050, г. Томск,  ул. Набережная реки Ушайки, д. 10</p></bio><bio xml:lang="en"><p>10, Naberejnaya Ushaiki, Tomsk, 634050</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Никитина</surname><given-names>Т. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Nikitina</surname><given-names>T. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>634050, г. Томск,  ул. Набережная реки Ушайки, д. 10</p></bio><bio xml:lang="en"><p>10, Naberejnaya Ushaiki, Tomsk, 634050</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Васильев</surname><given-names>С. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Vasiliev</surname><given-names>S. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Васильев Станислав Анатольевич</p><p>634050, г. Томск,  ул. Набережная реки Ушайки, д. 10</p><p> 634050, г. Томск,  пр. Ленина, д. 36</p></bio><bio xml:lang="en"><p>10, Naberejnaya Ushaiki, Tomsk, 634050</p><p>36, Lenin Avenue, Tomsk, 634050</p></bio><email xlink:type="simple">stanislav.vasilyev@medgenetics.ru</email><xref ref-type="aff" rid="aff-2"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>ФГБНУ Томский национальный исследовательский медицинский центр Российской академии наук, Научно-исследовательский институт медицинской генетики</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Tomsk National Research Medical Center of the Russian Academy of Sciences, Research Institute of Medical Genetics</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>ФГБНУ Томский национальный исследовательский медицинский центр Российской академии наук, Научно-исследовательский институт медицинской генетики; Национальный исследовательский Томский государственный университет</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Tomsk National Research Medical Center of the Russian Academy of Sciences, Research Institute of Medical Genetics; Tomsk State University</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2024</year></pub-date><pub-date pub-type="epub"><day>07</day><month>12</month><year>2024</year></pub-date><volume>23</volume><issue>10</issue><fpage>50</fpage><lpage>54</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Деменева В.В., Толмачева Е.Н., Филатова С.А., Зуев А.С., Ушакова А.С., Васильева О.Ю., Саженова Е.А., Никитина Т.В., Васильев С.А., 2024</copyright-statement><copyright-year>2024</copyright-year><copyright-holder xml:lang="ru">Деменева В.В., Толмачева Е.Н., Филатова С.А., Зуев А.С., Ушакова А.С., Васильева О.Ю., Саженова Е.А., Никитина Т.В., Васильев С.А.</copyright-holder><copyright-holder xml:lang="en">Demeneva V.V., Tolmacheva E.N., Filatova S.A., Zuev A.S., Ushakova A.S., Vasilyeva O.Y., Sazhenova E.A., Nikitina T.V., Vasiliev S.A.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.medgen-journal.ru/jour/article/view/2563">https://www.medgen-journal.ru/jour/article/view/2563</self-uri><abstract><sec><title>Введение</title><p>Введение. Эпигенетические процессы, такие как метилирование ДНК, играют важную роль в поддержании нормальной беременности и могут нарушаться при самопроизвольном аборте. Ранее нами был обнаружен повышенный уровень метилирования ретротранспозона LINE-1, составляющего около 17% генома человека, в ворсинах хориона спонтанных абортусов.</p></sec><sec><title>Цель</title><p>Цель: анализ уровня метилирования ретротранспозона LINE-1 в ворсинах хориона в эмбрионах из семей со спорадическим и привычным невынашиванием беременности.</p></sec><sec><title>Методы</title><p>Методы. В настоящем исследовании проведен анализ различий уровня метилирования в ворсинах хориона 46 медицинских абортусов (группа сравнения) и спонтанных абортусов из 155 семей со спорадическим и 127 семей с привычным невынашиванием беременности. Уровень метилирования LINE-1 был оценен методом таргетного бисульфитного массового параллельного секвенирования.</p></sec><sec><title>Результаты</title><p>Результаты. Не было обнаружено значимых различий уровня метилирования LINE-1 между группами с привычным и спорадическим невынашиванием беременности (p&gt;0,05). Однако уровень метилирования LINE-1 был значимо выше по сравнению с медицинскими абортусами (40,2 ± 2,2%) у спонтанных абортусов с моносомией X из семей с привычным (42,0 ± 4,5%, p=0,04) и спорадическим невынашиванием беременности (43,1 ± 5,2%, p=0,03) и у спонтанных абортусов с трисомией 16 из семей со спорадическим невынашиванием беременности (43,1 ± 3,9%, p&lt;0,001).</p></sec><sec><title>Заключение</title><p>Заключение. Нарушение уровня метилирования LINE-1 может быть маркером гибели части эмбрионов как при спорадическом, так и при привычном невынашивании беременности.</p></sec></abstract><trans-abstract xml:lang="en"><sec><title>Background</title><p>Background. Epigenetic processes such as DNA methylation play an important role in maintaining a normal pregnancy and their disruption may be associated with spontaneous abortion. Earlier, we found an increased level of methylation of the retrotransposon LINE-1, which makes up about 17% of the human genome, in the chorionic villi of spontaneous abortions.</p></sec><sec><title>Aim</title><p>Aim: to analyze the level of methylation of the LINE-1 retrotransposon in chorionic villi in embryos from families with sporadic and recurrent miscarriage.</p></sec><sec><title>Methods</title><p>Methods. The present study analyzes the differences in the level of methylation in chorionic villi of 46 induced abortions and spontaneous abortions from 155 families with sporadic miscarriage and 127 families with recurrent miscarriage. The methylation level of LINE-1 was assessed using targeted bisulfite massive parallel sequencing.</p></sec><sec><title>Results</title><p>Results. No significant differences in LINE-1 methylation levels were found between the groups with recurrent and sporadic miscarriage (p&gt;0.05). However, the LINE-1 methylation level was significantly higher compared to induced abortions (40.2 ± 2.2%) in spontaneous abortions with monosomy X from families with recurrent (42.0 ± 4.5%, p=0.04) and sporadic miscarriage (43.1 ± 5.2%, p=0.03), and in spontaneous abortions with trisomy 16 from families with sporadic miscarriage (43.1 ± 3.9%, p&lt;0.001).</p></sec><sec><title>Conclusion</title><p>Conclusion. Abnormal methylation level of LINE-1 may be a marker of the death of part of the embryos in both sporadic and recurrent miscarriage.</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>ретротранспозон LINE-1</kwd><kwd>привычное невынашивание беременности</kwd><kwd>ворсины хориона</kwd><kwd>метилирование ДНК</kwd></kwd-group><kwd-group xml:lang="en"><kwd>LINE-1 retrotransposon</kwd><kwd>recurrent miscarriage</kwd><kwd>chorionic villi</kwd><kwd>DNA methylation</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">Работа выполнена при поддержке гранта Российского научного фонда № 23-15-00341.</funding-statement><funding-statement xml:lang="en">The study was supported by the Russian Science Foundation grant No. 23-15-00341.</funding-statement></funding-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Quenby S., Gallos I.D., Dhillon-Smith R.K. et al. 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