ASD

 What are Genomic testing methods that determine the copy number of sequences can include chromosomal microarray(CMA) or targeted duplication analysis by fluorescence in situ hybridization (FISH). Note: The 7q11.23 duplication cannot be identified by routine analysis of G-banded chromosomes or other conventional cytogenetic banding techniques.

Chromosomal microarray (CMA) using oligonucleotide arrays or SNP genotyping arrays can detect the recurrentduplication in a proband. The ability to size the duplication depends on the type of microarray used and the density of probes in the 7q11.23 region.

Note: (1) Most individuals with the 7q11.23 duplication syndrome are identified by CMA performed in the context of evaluation of developmental delay, intellectual disability, and/or autism spectrum disorders. (2) This microduplication can be detected by BAC arrays.

Targeted duplication analysis. FISH analysis, quantitative PCR (qPCR), multiplex ligation-dependent probeamplification (MLPA), or other targeted quantitative methods may be used to test relatives of a proband known to have the 7q11.23 duplication.

Note: (1) Targeted duplication testing is not appropriate for an individual in whom the 7q11.23 duplication was not detected by CMA designed to target this region. (2) It is not possible to size the duplication routinely by use of targeted methods Coutsey ;GeneReviews® chapters are owned by the University of Washington. Permission is hereby granted to reproduce, distribute, and translate copies of content materials for noncommercial research purposes only, provided that (i) credit for source (http://www.genereviews.org/) and copyright (© 1993-2016 University of Washington) are included with each copy; (

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Table 1.

Summary of Molecular Genetic Testing Used in 7q11.23 Duplication Syndrome

Duplication 1	ClinGen ID 2	Region Location 3, 4	Test Method	Test Sensitivity
				Proband	At-risk family members
1.5- to 1.8-Mb heterozygousduplication at 7q11.23	ClinGen-37392	GRCh37/hg19 chr7:72,744,454-74,142,513	CMA 5	100%	100%
			Targetedduplicationanalysis 6	Not applicable 7	100% 8

1.

See Molecular Genetics for details of the duplication.

2.

Standardized clinical annotation and interpretation for genomic variants from the Clinical Genome Resource (ClinGen) project(formerly the International Standards for Cytogenomic Arrays (ISCA) Consortium)

3.

Genomic coordinates represent the minimum duplication size associated with the 7q11.23 duplication as designated by ClinGen. Duplication coordinates may vary slightly based on array design used by the testing laboratory. Note that the size of the microduplication as calculated from these genomic positions may differ from the expected microduplication size due to the presence of segmental duplications near breakpoints. The phenotype of significantly larger or smaller microduplications within this region may be clinically distinct from the 7q11.23 duplication (see Genotype/Phenotype Correlations).

4.

See Molecular Genetics for genes of interest included in this region.

5.

Chromosomal microarray analysis (CMA) using oligonucleotide arrays or SNP genotyping arrays. CMA designs in current clinical use target the 7q11.23 region.

6.

Targeted duplication analysis methods can include: FISH, quantitative PCR (qPCR), and multiplex ligation-dependent probeamplification (MLPA) as well as other targeted quantitative methods.

7.

Targeted duplication analysis is not appropriate for an individual in whom the 7q11.23 duplication was not detected by CMA designed to target this region.

8.

Targeted duplication analysis may be used to test at-risk relatives of a proband known to have the 7q11.23 duplication.