An algorithm for the diagnosis of X-linked intellectual disability in children
https://doi.org/10.21508/1027-4065-2016-61-5-34-41
Abstract
X-linked intellectual disability (XLID) is a clinically and genetically heterogeneous group of hereditary diseases caused by mutations on the X chromosome, which lead to impaired intellectual development. The paper determines for the first time the proportion of X-linked diseases (6.54%) in the pattern of intellectual disability in children. A system has been developed to quantify the clinical severity of fragile X mental retardation syndrome and Rett syndrome. A system has been scientifically justified to predict the clinical severity, which is based on an analysis of the impact of genetic and epigenetic factors (mutation type and location, X chromosome inactivation). The authors have determined the contribution of nonrandom X inactivation to the clinical polymorphism of various forms of XLID and established its role as an important diagnostic marker for pathology. It is shown that the study of X chromosome inactivation can identify asymptomatic female carriers of X-linked mutations to provide medical genetic counseling to families. An algorithm has been elaborated to diagnose XLID among the undifferentiated forms of mental developmental abnormalities in children.
About the Authors
V. Yu. Voinova
Academician Yu.E. Veltishchev Research Clinical Institute of Pediatrics, N.I. Pirogov Russian National Research Medical University, Ministry of Health of Russia, Moscow;
Moscow State University of Psychology and Pedagogy, Moscow
Russian Federation
Russian Federation
S. G. Vorsanova
Academician Yu.E. Veltishchev Research Clinical Institute of Pediatrics, N.I. Pirogov Russian National Research Medical University, Ministry of Health of Russia, Moscow
Russian Federation
Russian Federation
Yu. B. Yurov
Mental Health Research Center, Russian Academy of Sciences, Moscow
Russian Federation
Russian Federation
I. Yu. Yurov
Mental Health Research Center, Russian Academy of Sciences, Moscow;
Russian Medical Academy of Postgraduate Education, Moscow
Russian Federation
Russian Federation
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Review
For citations:
Voinova V.Yu., Vorsanova S.G., Yurov Yu.B., Yurov I.Yu. An algorithm for the diagnosis of X-linked intellectual disability in children. Rossiyskiy Vestnik Perinatologii i Pediatrii (Russian Bulletin of Perinatology and Pediatrics). 2016;61(5):34-41. (In Russ.) https://doi.org/10.21508/1027-4065-2016-61-5-34-41
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