The pathogenicity of genomic/genetic variant of X-chromosomal genes in males with intellectual disability
Received date: 2016-11-30
Revised date: 2017-01-23
Online published: 2017-03-20
Supported by
the National Nature Science Foundation of China(31671310);the National Nature Science Foundation of Beijing(7162029);the Innovation Project of Beijing Municipal Human Resources and Social Secutity Bureauand the Capital Health Research and Development of Special(2014-2-1131)
Intellectual Disability (ID, previously named mental retardation) is a group of common pediatric neurology disorders characterized by extensive genetic and phenotypic heterogeneity. About 25%-50% of ID was caused by genomic/genetic variants, in which genomic/genetic variants of X-chromosome are one of key pathogenic causation (25%-30%), resulting in X-linked ID (XLID). The epidemiological data showed that the male to female ratio is 1.3: 1 in ID patients. The prevalence of XLID in the whole ID population is 10%-15%, and this prevalence reaches 20%-25% in the male ID population. This sex-related differential proportion of ID may be attributed to hemizygosity of X chromosomes in males. A quick detection of genomic/genetic aberrations of X chromosome is feasible and available now due to the overwhelming development of next-generation genomic techniques and their clinical applications; in particular, whole exome sequencing, customer-designed whole genomic chip for the X chromosome, high-density target sequencing and whole X chromosomal sequencing are used widely for clinical diagnosis. In this review, we systematically summarize the pathogenicity and characteristics of X-chromosomal genomic/genetic aberrations in the male patients with ID, and how the new technologies have been used to detect X-chromosomal abnormalities. This review will help researchers understand the pathogenicity of X-chromosomal variations in male ID patients from the view of whole genome, refresh the knowledge about the genomic/genetic etiology of ID, and further provide a theoretical basis for genetic counseling and prenatal diagnosis in the future.
Jiping Peng,Fang Liu,Hua Xie,Xiaoli Chen . The pathogenicity of genomic/genetic variant of X-chromosomal genes in males with intellectual disability[J]. Hereditas(Beijing), 2017 , 39(6) : 455 -468 . DOI: 10.16288/j.yczz.16-407
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