Use of clinical chromosomal microarray in Chinese patients with autism spectrum disorder - implications of a copy number variation involving dpp10 (Perkin Elmer CGX)

ABSTRACT: Background Array-Comparative-Genomic-Hybridization (aCGH) is recommended as first-tier genetic test for children with autism spectrum disorder (ASD). However, result interpretation can be challenging as copy number variants (CNVs) in non-European ASD patients is not well studied. To address this literature gap, we report the CNV findings in a cohort of Chinese children with ASD. Methods DNA samples were obtained from 258 Chinese ASD patients recruited from a child assessment center between January 2011 and August 2014. aCGH was performed using NimbleGen-CGX-135k or Agilent-CGX 60k oligonucleotide array. Results were classified based on existing guidelines and literature. Results Ten pathogenic and one likely-pathogenic CNVs were found in nine patients, with an overall diagnostic yield of 3.5%. A 138kb duplication involving 3’ exons of DPP10 (hg[19]chr2:116534689-116672358), reported to be associated with ASD, was identified in one patient (0.39%). The same CNV was reported as variant of unknown significance (VUS) in DECIPHER database. Multiple individuals of typical development carrying a similar duplication were identified amongst our ancestry-matched control with frequency of 6/653 (0.92%) as well as from literature and genomic databases. Conclusions DPP10 duplication is likely a benign CNV polymorphism enriched in Southern Chinese with population frequency of ~1%. This highlights the importance of using ancestry-matched controls in interpretation of aCGH findings.

ORGANISM(S): Homo sapiens

SUBMITTER: Wing Fai TANG 

PROVIDER: E-MTAB-5672 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress