Cytogenetic abnormalities and fragile-x syndrome in Autism Spectrum Disorder

Reddy, Kavita S.

doi:10.1186/1471-2350-6-3

Cited by 180 publications

(129 citation statements)

References 124 publications

Supporting

Mentioning

123

Contrasting

Unclassified

Order By: Relevance

“…Continued improvements in cytogenetic approaches, including higher-resolution studies, have increased the diagnostic yield of conventional cytogenetic studies to approximately 3%. [24][25][26] Numerous cytogenetically detectable deletions and duplications have been associated with an ASD phenotype. 27 In general, the most commonly reported loci mirror the reported linkage data.…”

Section: Chromosomal Abnormalitiesmentioning

confidence: 99%

Clinical genetics evaluation in identifying the etiology of autism spectrum disorders: 2013 guideline revisions

Schaefer

Mendelsohn

2013

Genetics in Medicine

453

393

View full text Add to dashboard Cite

Autism spectrum disorders (ASDs), also known as pervasive developmental disorders, are a behaviorally defined group of neurodevelopmental disorders that are usually diagnosed in early childhood. They are characterized by varying degrees of limitations in communication and social interaction and by atypical, repetitive behaviors with an onset before 3 years of age. The phenotype of ASDs is extremely heterogeneous, with differences from person to person in a wide range of symptoms and severity as well as differences between the various subtypes of ASDs (e.g., autistic disorder, Asperger syndrome, and pervasive developmental disorder not otherwise specified).Multiple lines of epidemiologic evidence support the strong role of genetics in the etiology of ASDs. 1-3 Results of population studies of unselected cases of autism are most consistent with multifactorial inheritance. Until quite recently, the accepted recurrence risk for full siblings of a child with autism has been in the range of 3-10%. [4][5][6] Overall, only 2-3% of families have more than one affected child (possibly because of voluntary avoidance of pregnancy after a child is diagnosed). Most studies have reported a sex bias in the recurrence risk in keeping with the presumption of a "multifactorial" mode of inheritance (higher risk if the affected person is of the less commonly affected sex). As such, the reported risk is 7% of another affected child if the first affected child is female and 4% if the first affected child is male. 7 If multiple children (two or more) have autism, the recurrence risk is on the order of 33-50% for any future pregnancy. 7 Two recent studies 8,9 have reported even higher recurrence risks of 11 and 19% with single-sibling involvement. The first 8 was a retrospective self-enrolled/self-identified study using an interactive website. The diagnosis was confirmed, but the identification of second siblings may be a source of ascertainment bias. The second 9 was an international multisite prospective study in 664 families with a calculated 19% recurrence risk. Interestingly, the typically reported sex bias was not noted in one of these studies. 8 Both were single studies that bear replication.The autism spectrum disorders are a collective of conditions that have in common impaired socialization and communication in association with stereotypic behaviors. The reported incidence of autism spectrum disorders has increased dramatically over the past two decades. In addition, increased attention has been paid to these conditions by both lay and professional groups. These trends have resulted in an increase in the number of referrals to clinical geneticist for the evaluation of persons with autism spectrum disorders. The primary roles of the geneticist in this process are to define etiology when possible, to provide genetic counseling, and to contribute to case management. In deciding on the appropriate evaluation for a particular patient, the geneticist will consider a host of factors: (i) ensuring an accurate diagnosis of autism befor...

show abstract

Section: Chromosomal Abnormalitiesmentioning

confidence: 99%

Clinical genetics evaluation in identifying the etiology of autism spectrum disorders: 2013 guideline revisions

Schaefer

Mendelsohn

2013

Genetics in Medicine

453

393

View full text Add to dashboard Cite

show abstract

“…56,57 About 2-5% of the children and adolescents diagnosed with AD carry a full FRAXA mutation or FRAXA mosaics. 9,13,16,58 Despite this finding, no linkage or association with FMR1 gene variants 59,60 or the FRAXA mutation has been found in large samples diagnosed with AD by strict criteria. 61,62 As the diagnosis of FRAXA, however, has major implications for genetic counselling, it should be ruled out in all individuals with AD and mildto-severe mental retardation.…”

Section: Single Gene Disorders Associated With Admentioning

confidence: 95%

“…It has been discussed if the suspected increase in prevalence of AD might be caused primarily by cytogenetic pathologies. 13 Shortcomings of most cytogenetic studies are the lack of standardized assessment methods for AD, the inclusion of subjects with autistic features but no clear AD diagnosis and the lack of standardized assessment of cognitive and adaptive functioning.…”

Section: Cytogenetic Findings and Genetic Syndromes In Admentioning

confidence: 99%

See 1 more Smart Citation

The genetics of autistic disorders and its clinical relevance: a review of the literature

2006

View full text Add to dashboard Cite

Twin and family studies in autistic disorders (AD) have elucidated a high heritability of the narrow and broad phenotype of AD. In this review on the genetics of AD, we will initially delineate the phenotype of AD and discuss aspects of differential diagnosis, which are particularly relevant with regard to the genetics of autism. Cytogenetic and molecular genetic studies will be presented in detail, and the possibly involved aetiopathological pathways will be described. Implications of the different genetic findings for genetic counselling will be mentioned.

show abstract

“…The diagnostic yield of ASD genetic testing varies from 0.5% to 18%, depending on the type of testing. [7][8][9][10] Although genetic testing is now a standard of care and an integral part of evaluation of ASD, a genetic cause is identified in <25% of patients with ASD. 11 With the advancement of genomic technologies, another potential test-massively parallel sequencing (e.g., whole-exome and whole-genome sequencing analysis)-is gradually moving from the research laboratory to clinical settings for the identification of single genes associated with ASD.…”

Section: Introductionmentioning

confidence: 99%

Autism genetic testing: a qualitative study of awareness, attitudes, and experiences among parents of children with autism spectrum disorders

Chen

Liu

Huang

et al. 2013

Genetics in Medicine

View full text Add to dashboard Cite

Purpose:The goal of this first-of-its-kind qualitative study was to examine the awareness, attitudes, and experiences among parents of autistic children regarding autism genetic testing. Methods:We conducted in-depth, individual, and semistructured interviews with 42 parents of autistic children with diverse racial/ethnic backgrounds. All interviews were audio-taped, transcribed, and coded into major themes and subthemes.Results: Approximately one-quarter of participants had two or more autistic children, and about half of them were ethnic/racial minorities. The majority of participants postulated favorable attitudes toward autism genetic testing for three main reasons: early intervention and treatment, identifying the etiology of autism, and informed family planning. Nevertheless, among parents who had taken their children for genetic testing, some expressed frustration and questioned the competency of their providers in interpreting test results. Asian parents and those with a low socioeconomic status expressed lower awareness and tended to have more limited access to autism genetic testing. Conclusion:As health-care providers play a vital role in providing genetic services and education, these professionals should be educated and be sensitive to the needs of parents with autistic children. Further quantitative research is required to examine the effects of socio-demographic factors on parents' awareness, attitudes, and experiences regarding autism genetic testing. Genet Med 2013:15(4):274-281

show abstract

Cytogenetic abnormalities and fragile-x syndrome in Autism Spectrum Disorder

Cited by 180 publications

References 124 publications

Clinical genetics evaluation in identifying the etiology of autism spectrum disorders: 2013 guideline revisions

Clinical genetics evaluation in identifying the etiology of autism spectrum disorders: 2013 guideline revisions

The genetics of autistic disorders and its clinical relevance: a review of the literature

Autism genetic testing: a qualitative study of awareness, attitudes, and experiences among parents of children with autism spectrum disorders

Contact Info

Product

Resources

About