Biomaterial Database

Genetic testing in children and adolescents with intellectual disability. 2018

Nick Bass, and David Skuse

Division of Psychiatry, University College London.

Investigation for genetic causes of intellectual disability has advanced rapidly in recent years. We review the assessment of copy number variants (CNVs) and the use of next-generation sequencing based assays to identify single nucleotide variation in intellectual disability. We discuss the diagnostic yields that can be expected with the different assays. There is high co-morbidity of intellectual disability and psychiatric disorders. We review the relationship between variants which are pathogenic for intellectual disability and the risk of child and adolescent onset psychiatric disorders. The diagnostic yields from genome wide CNV analysis and whole exome sequence analysis are high - in the region of 15 and 40%, respectively - but vary according to exact referral criteria. Many variants pathogenic for intellectual disability, notably certain recurrent CNVs, have emerged as strong risk factors for other neurodevelopmental disorders such as autism spectrum disorders, attention deficit hyperactivity disorder, and schizophrenia. It is now conceivable that etiological variants could be identified in the majority of children presenting with intellectual disability using next-generation sequencing based assays. However, challenges remain in assessment of the pathogenicity of variants, reporting of incidental findings in children and determination of prognosis, particularly in relation to psychiatric disorders.

UI	MeSH Term	Description	Entries
D008607	Intellectual Disability	Subnormal intellectual functioning which originates during the developmental period. This has multiple potential etiologies, including genetic defects and perinatal insults. Intelligence quotient (IQ) scores are commonly used to determine whether an individual has an intellectual disability. IQ scores between 70 and 79 are in the borderline range. Scores below 67 are in the disabled range. (from Joynt, Clinical Neurology, 1992, Ch55, p28)	Disability, Intellectual,Idiocy,Mental Retardation,Retardation, Mental,Deficiency, Mental,Intellectual Development Disorder,Mental Deficiency,Mental Retardation, Psychosocial,Deficiencies, Mental,Development Disorder, Intellectual,Development Disorders, Intellectual,Disabilities, Intellectual,Disorder, Intellectual Development,Disorders, Intellectual Development,Intellectual Development Disorders,Intellectual Disabilities,Mental Deficiencies,Mental Retardations, Psychosocial,Psychosocial Mental Retardation,Psychosocial Mental Retardations,Retardation, Psychosocial Mental,Retardations, Psychosocial Mental
D002648	Child	A person 6 to 12 years of age. An individual 2 to 5 years old is CHILD, PRESCHOOL.	Children
D005820	Genetic Testing	Detection of a MUTATION; GENOTYPE; KARYOTYPE; or specific ALLELES associated with genetic traits, heritable diseases, or predisposition to a disease, or that may lead to the disease in descendants. It includes prenatal genetic testing.	Genetic Predisposition Testing,Genetic Screening,Predictive Genetic Testing,Predictive Testing, Genetic,Testing, Genetic Predisposition,Genetic Predictive Testing,Genetic Screenings,Genetic Testing, Predictive,Predisposition Testing, Genetic,Screening, Genetic,Screenings, Genetic,Testing, Genetic,Testing, Genetic Predictive,Testing, Predictive Genetic
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000293	Adolescent	A person 13 to 18 years of age.	Adolescence,Youth,Adolescents,Adolescents, Female,Adolescents, Male,Teenagers,Teens,Adolescent, Female,Adolescent, Male,Female Adolescent,Female Adolescents,Male Adolescent,Male Adolescents,Teen,Teenager,Youths
D056915	DNA Copy Number Variations	Stretches of genomic DNA that exist in different multiples between individuals. Many copy number variations have been associated with susceptibility or resistance to disease.	Copy Number Polymorphism,DNA Copy Number Variant,Copy Number Changes, DNA,Copy Number Polymorphisms,Copy Number Variants, DNA,Copy Number Variation, DNA,DNA Copy Number Change,DNA Copy Number Changes,DNA Copy Number Polymorphism,DNA Copy Number Polymorphisms,DNA Copy Number Variants,DNA Copy Number Variation,Polymorphism, Copy Number,Polymorphisms, Copy Number
D059014	High-Throughput Nucleotide Sequencing	Techniques of nucleotide sequence analysis that increase the range, complexity, sensitivity, and accuracy of results by greatly increasing the scale of operations and thus the number of nucleotides, and the number of copies of each nucleotide sequenced. The sequencing may be done by analysis of the synthesis or ligation products, hybridization to preexisting sequences, etc.	High-Throughput Sequencing,Illumina Sequencing,Ion Proton Sequencing,Ion Torrent Sequencing,Next-Generation Sequencing,Deep Sequencing,High-Throughput DNA Sequencing,High-Throughput RNA Sequencing,Massively-Parallel Sequencing,Pyrosequencing,DNA Sequencing, High-Throughput,High Throughput DNA Sequencing,High Throughput Nucleotide Sequencing,High Throughput RNA Sequencing,High Throughput Sequencing,Massively Parallel Sequencing,Next Generation Sequencing,Nucleotide Sequencing, High-Throughput,RNA Sequencing, High-Throughput,Sequencing, Deep,Sequencing, High-Throughput,Sequencing, High-Throughput DNA,Sequencing, High-Throughput Nucleotide,Sequencing, High-Throughput RNA,Sequencing, Illumina,Sequencing, Ion Proton,Sequencing, Ion Torrent,Sequencing, Massively-Parallel,Sequencing, Next-Generation