Neuromuscular DiseasesNeuromuscular DiseasesНервно-мышечные болезни2222-87212413-0443Publishing House ABV Press5510.17650/2222-8721-2013-0-3-27-31LECTURES AND REVIEWSЛЕКЦИИ И ОБЗОРЫProximal spinal muscular atrophy types I-IV: Specific features of molecular genetic diagnosisПроксимальная спинальная мышечная атрофия типов I–IV: особенности молекулярно-генетической диагностикиZabnenkovaV. V.ЗабненковаВ. В.
Russian Federation
V_Zabnenkova@dnalab.ruDadaliE. L.ДадалиЕ. Л.
Russian Federation
PolyakovA. V.ПоляковА. В.
Russian Federation
Research Center of Medical Genetics, Russian Academy of Medical Sciences, MoscowФГБУ «Медико-генетический научный центр» РАМН, Москва200920133327312002201520022015Copyright ©; 2013, Zabnenkova V.V., Dadali E.L., Polyakov A.V.Copyright ©; 2013, Забненкова В.В., Дадали Е.Л., Поляков А.В.2013Zabnenkova V.V., Dadali E.L., Polyakov A.V.Забненкова В.В., Дадали Е.Л., Поляков А.В.https://creativecommons.org/licenses/by/4.0https://nmb.abvpress.ru/jour/article/view/55

Proximal spinal muscular atrophy (SMA) types I-IV is the most common autosomal recessive neuromuscular disease caused by mutations in the SMN1 gene encoding the survival motor neuron protein. It is characterized by progressive muscle weakness due to injury of the motor neurons of the anterior horns of the spinal cord. The classification of the disease is based on the time of its onset, severity, and survival. The detection of the major mutation of exon 7 and/or 8 deletion in the SMN1 gene is a qualitative reliable and sensitive diagnostic test. The SMN1 gene has the almost complete homolog SMN2 gene, which hampers the analysis of heterozygous carriage of the disease. So the determination of the carriage status is based on the quantitative analysis of the number of SMN1 gene copies. The paper covers problems and new possibilities in themolecular genetic diagnosis of proximal SMA.

Проксимальная спинальная мышечная атрофия (СМА) типов I–IV – наиболее частое аутосомно-рецессивное нейромышечное заболевание, вызываемое мутациями в гене SMN1, кодирующем белок выживаемости мотонейронов. Характеризуется прогрессирующей мышечной слабостью вследствие поражения двигательных нейронов передних рогов спинного мозга. Классификация заболевания основана на времени его начала, тяжести течения и продолжительности жизни. Выявление мажорной мутации делеции экзонов 7 и/или 8 гена SMN1 является качественным, надежным и чувствительным диагностическим тестом. Ген SMN1 имеет почти полный гомолог – ген SMN2, что затрудняет анализ гетерозиготного носительства заболевания. Поэтому определение статуса носителя основано на количественном анализе числа копий гена SMN1. В работе освещаются проблемы и новые возможности в молекулярно-генетической диагностике проксимальной СМА.

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