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Published on: August 15, 2019
[Analysis of IQSEC2 gene variant in a child with X-linked mental retardation]
Jianbo Zhao1, Xinying Yang, Jiuwei Li
1Department of Neurology, Beijing Children' s Hospital, Capital Medical University, National Center for Children' s Health, Beijing 100045, China. 13910150389@163.com.
Objective:
To analyze the clinical phenotype and genetic variants of a child with X-linked mental retardation caused by IQSEC2 gene mutation, and provide reference for the diagnosis of the disease.
Methods:
The child was subjected to next generation sequencing (NGS), and the diagnosis was made by taking consideration of her clinical characteristics.
Results:
The child has presented with global developmental delay, particularly in fine motor skill and language development, in addition with intellectual disability. Genetic testing revealed that she has harbored a heterozygous c.1861dup variant of the IQSEC2 gene, which was not detected in either parent.
Conclusion:
The de novo c.186ldup variant of the IQSEC2 gene probably underlay the X-linked mental retardation in this child. Above finding has, expanded the spectrum of IQSEC2 gene mutations and provide a basis for the diagnosis of similar cases.
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