Genetic variant spectrum in patients with severe intellectual developmental disorder identified by exome sequencing
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Abstract
To investigate the spectrum of genetic variants and describe the clinical characteristics of patients with severe intellectual disability (ID) we conducted a cross-sectional descriptive study on 18 patients by exome sequencing (ES/WES) at the Clinical genetics center - Hanoi Medical University Hospital. Results showed 3 cases carried variants in MECP2 (16.7%), while the remaining 15 cases harbored variants distributed across various other genes (83.3%). The MECP2 group showed a higher rate of epilepsy than the group with variants in other genes (66.7% vs. 26.7%); however, this difference was not statistically significant, likely due to the small sample size (p = 0.245). No statistically significant differences were observed between the two groups in age at symptom onset, neurodevelopmental regression, or autistic features. In conclusion, in addition to MECP2 variants - which were the most frequently identified variant - 15 other variants were detected across different genes. These findings support the clinical utility of exome sequencing as an effective diagnostic approach for identifying the genetic causes of severe intellectual disability.
Article Details
Keywords
Intellectual disability, severe intellectual disability, MECP2, genetic variants, whole exome sequencing
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