title: Genetic diagnosis of autism spectrum disorders: the opportunity and challenge in the genomics era.
abstract: A genetic etiology for autism spectrum disorders (ASDs) was first suggested from twin studies reported in the 1970s. The identification of gene mutations in syndromic ASDs provided evidence to support a genetic cause of ASDs. More recently, genome-wide copy number variant and sequence analyses have uncovered a list of rare and highly penetrant copy number variants (CNVs) or single nucleotide variants (SNVs) associated with ASDs, which has strengthened the claim of a genetic etiology for ASDs. Findings from research studies in the genetics of ASD now support an important role for molecular diagnostics in the clinical genetics evaluation of ASDs. Various molecular diagnostic assays including single gene tests, targeted multiple gene panels and copy number analysis should all be considered in the clinical genetics evaluation of ASDs. Whole exome sequencing could also be considered in selected clinical cases. However, the challenge that remains is to determine the causal role of genetic variants identified through molecular testing. Variable expressivity, pleiotropic effects and incomplete penetrance associated with CNVs and SNVs also present significant challenges for genetic counseling and prenatal diagnosis.
authors.affiliation: Department of Pediatrics and Neurobiology, Duke University School of Medicine , Durham, NC , USA .
authors.forename: Yong-Hui
authors.initials: YH
authors.lastname: Jiang
authors.forename: Yi
authors.initials: Y
authors.lastname: Wang
authors.forename: Xu
authors.initials: X
authors.lastname: Xiu
authors.forename: Kwong Wai
authors.initials: KW
authors.lastname: Choy
authors.forename: Amber Nolen
authors.initials: AN
authors.lastname: Pursley
authors.forename: Sau W
authors.initials: SW
authors.lastname: Cheung
mesh_terms: D002648:Child; D002659:Child Development Disorders, Pervasive / Q000175:diagnosis / Q000235:genetics; D055028:Comparative Genomic Hybridization; D056915:DNA Copy Number Variations; D005820:Genetic Testing; D023281:Genomics; D006801:Humans; D020411:Oligonucleotide Array Sequence Analysis; D020641:Polymorphism, Single Nucleotide; D017422:Sequence Analysis, DNA
keywords: Autism spectrum disorders; array comparative genomic hybridization; copy number variation; prenatal diagnosis; single nucleotide variant; whole exome sequencing; whole genome sequencing