Indian Journal of Medical Research

ORIGINAL ARTICLE
Year
: 2015  |  Volume : 142  |  Issue : 6  |  Page : 699--712

Recurrent benign copy number variants & issues in interpretation of variants of unknown significance identified by cytogenetic microarray in Indian patients with intellectual disability


Vijay Raju Boggula1, Meenal Agarwal1, Rashmi Kumar2, Shally Awasthi2, Shubha R Phadke1 
1 Department of Medical Genetics, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India
2 Department of Pediatrics, King George's Medical University, Lucknow, India

Correspondence Address:
Shubha R Phadke
Department of Medical Genetics, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Rae Bareilly Road, Lucknow 226 014, Uttar Pradesh
India

Background & objectives: Cytogenetic microarray (CMA) is now recommended as a first-tier clinical diagnostic test in cases with idiopathic intellectual disability and/or developmental delay (ID/DD). Along with clinically relevant variants, CMA platforms also identify variants of unknown significance (VUS). This study was done to look for utility and various issues in interpretation of copy number variants (CNVs) in Indian patients with ID/DD. Methods: The CMA was performed in 86 Indian patients with idiopathic ID/DD with or without dysmorphic features. CNV was reported if copy number gain was >400 kb in size and copy number loss was > 200 kb in size. Results: Pathogenic CNVs were found in 18 of 86 (20.9%) patients. One large (14 Mb size) de novo heterozygous copy number gain was found in one patient. VUS (total 31) were present in 17 of 86 (19.7%) patients. Five novel recurrent benign CNVs were also present in our patients. Interpretation & conclusions: Our findings highlight the difficulties in interpretation of CNVs identified by CMA. More Indian data on VUS and recurrent benign CNVs will be helpful in the interpretation of CMA in patients with ID/DD.


How to cite this article:
Boggula VR, Agarwal M, Kumar R, Awasthi S, Phadke SR. Recurrent benign copy number variants & issues in interpretation of variants of unknown significance identified by cytogenetic microarray in Indian patients with intellectual disability.Indian J Med Res 2015;142:699-712


How to cite this URL:
Boggula VR, Agarwal M, Kumar R, Awasthi S, Phadke SR. Recurrent benign copy number variants & issues in interpretation of variants of unknown significance identified by cytogenetic microarray in Indian patients with intellectual disability. Indian J Med Res [serial online] 2015 [cited 2020 Oct 27 ];142:699-712
Available from: https://www.ijmr.org.in/article.asp?issn=0971-5916;year=2015;volume=142;issue=6;spage=699;epage=712;aulast=Boggula;type=0