medgenМедицинская генетикаMedical Genetics2073-7998Publishing House «Genius Media» LLC10.25557/2073-7998.2021.07.45-58medgen-1948Research ArticleОРИГИНАЛЬНЫЕ ИССЛЕДОВАНИЯORIGINAL RESEARCHГенетические формы задержки психического развития и умственной отсталости в практике работы медико-генетической консультации Медико-генетического научного центраGenetic forms of developmental delay and intellectual disability in the practice of the medical genetic consultation of Research Centre for Medical GeneticsАнисимоваИ. В.AnisimovaI. V.anisimova-inga@med-gen.ruФГБНУ «Медико-генетический научный центр имени академика Н.П. Бочкова»РоссияResearch Centre for Medical GeneticsRussian Federation2021281020212074558Copyright © Анисимова И.В., 20212021Анисимова И.В.Anisimova I.V.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://www.medgen-journal.ru/jour/article/view/1948

Задержка психического развития (ЗПР) и умственная отсталость (УО) являются частыми причинами направления пациентов на медико-генетическое консультирование. Наблюдаемый в последние годы значительный рост числа нозологических форм моногенных и хромосомных болезней среди пациентов с ЗПР или УО медико-генетической консультации Медико-генетического научного центра отражает повышение эффективности диагностики наследственных форм данной патологии. Цели исследования: оценка долей клинически и/или лабораторно подтвержденных хромосомных, моногенных заболеваний и болезней геномного импринтинга, диагностированных у пациентов с ЗПР или УО; определение эффективности разных методов диагностики генетических форм ЗПР и УО; расчет сегрегационной частоты для оценки вклада моногенных форм с аутосомно-рецессивным и X-сцепленным рецессивным типами наследования в недифференцированные ЗПР и УО. Выборка включала 2350 пациентов с ЗПР или УО различных степеней тяжести и пациентов с диагнозом, предполагающим развитие ЗПР или УО по мере взросления, проконсультированных врачами-генетиками консультативного и научно-консультативного отделов Медико-генетического научного центра им. Бочкова в 2006, 2007, 2016 гг. и первой половине 2017 г. В исследуемый период (2006, 2007, 2016 и первая половина 2017 г.) отмечается тенденция к снижению доли хромосомной патологии среди всех пациентов выборки. В группе пациентов с ЗПР или УО с аномалиями хромосом с течением времени отмечается значительный рост доли структурной хромосомной патологии и снижение доли заболеваний, обусловленных изменением числа хромосом. Доля моногенных форм остается практически неизменной в исследуемый период. Внутри данной группы отмечается некоторый рост доли аутосомно-доминантной патологии. Доля пациентов с ЗПР или УО, обусловленных болезнями геномного импринтинга, достоверно различается в исследуемые годы, со временем отмечается тенденция к ее уменьшению. Доля только клинически установленных синдромов без лабораторного подтверждения значительно снижается в исследуемый период. Максимальная диагностическая эффективность среди лабораторных генетических методов показана для микросателлитного анализа, MLPA, хромосомного микроматричного анализа и секвенирования нового поколения.

Developmental delay (DD) and intellectual disability (ID) are frequent reasons for referring patients for medical genetic counseling. A significant increase in the number of nosological forms of monogenic and chromosomal diseases among patients with DD or ID in medical genetic consultation of Bochkov Research Centre for Medical Genetics in recent years reflects an increase in its effectiveness in diagnosing this pathology. Purpose of the research: 1. To estimate the proportion of clinically and/or laboratory-confirmed chromosomal, monogenic, and genomic imprinting disorders diagnosed in patients with DD or ID consulted by geneticists from the consultation and scientific consulting departments of the Bochkov Research Centre for Medical Genetics in 2006, 2007, 2016, and the first half of 2017. 2. Determination of the effectiveness of different diagnostic methods of genetic forms DD and ID. 3. Calculation of segregation frequency to estimate the contribution of monogenic forms with autosomal recessive and X-linked recessive types of inheritance among undifferentiated cases of DD and ID. The sampling for the analysis included 2350 patients with DD or ID of varying severity, as well as patients with a diagnosis suggesting the development of DD or ID as they mature, consulted by geneticists from the consultation and scientific consulting departments of the Bochkov Research Centre for Medical Genetics in 2006, 2007, 2016, and the first half of 2017. During the research period (2006, 2007, 2016, and the first half of 2017), there was a decreasing trend in the proportion of chromosomal pathology among all patients of the sampling. Within the group of patients with DD or ID with chromosomal pathology, a significant increase in the proportion of structural chromosomal pathology and a decrease in the proportion of diseases caused by changes in the number of chromosomes is noted over time. The proportion of monogenic forms remains practically unchanged during the study period. Within this group, there is some increase in the share of AD pathology. The proportion of patients with DD or ID caused by genomic imprinting disorders varies significantly in the years studied, with a tendency to decrease over time. The proportion of only clinically identified syndromes without laboratory confirmation decreases significantly during the study period. The maximum diagnostic efficiency among laboratory genetic methods has been shown for microsatellite analysis, MLPA, chromosomal microarray analysis (CMA) and next generation sequencing (NGS).

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The authors declare that there are no conflicts of interest present.