Confirmation: A crucial step in copy number variation analysis after exome sequencing in intellectual disabilities

Authors

  • C.A.M. Heeswijk, van
  • Hans Bokhoven, van

DOI:

https://doi.org/10.26481/marble.2015.v6.370

Abstract

Intellectual disability (ID) comprises a group of mental disorders which have underlying genetic causes, among which the monogenic causes are one of the causes for ID. One kind of a monogenic cause is the copy number variations (CNVs). These CNVs can be indicated using exome sequencing (ES) and the CoNVex and CoNIFER algorithms. To confirm the possible causative CNVs quantitative PCR (QPCR) was used. In a Pakistani ID patient a homozygous deletion of ENTPD3 was indicated and in an Estonian ID patient CPVL-CHN2 a homozygous duplication was indicated. However the QPCR showed that ENTPD3 did not segregate and CPVL-CHN2 was only duplicated heterozygous. Confirmation, like QPCR, is therefore a crucial step in confirming CNVs analysis of ES in ID patients.

References

American Psychiatric Association. Diagnostic and statistical manual of metal disorders. Washington, DC: American Psychiatric Association,; 2000.

van Bokhoven H. Genetic and epigenetic networks in intellectual disabilities. Annual review of genetics. 2011;45:81-104.

Cooper GM, Coe BP, Girirajan S, Rosenfeld JA, Vu TH, Baker C, et al. A copy number variation morbidity map of developmental delay. Nature genetics. 2011;43(9):838-46.

Gilissen C, Hoischen A, Brunner HG, Veltman JA. Disease gene identification strategies for exome sequencing. European Journal of Human Genetics. 2012;20(5):490-7.

Biesecker LG. Exome sequencing makes medical genomics a reality. Nature genetics. 2010;42(1):13-4.

Krumm N, Sudmant PH, Ko A, O’Roak BJ, Malig M, Coe BP, et al. Copy number variation detection and genotyping from exome sequence data. Genome research. 2012;22(8):1525-32.

Amarasinghe KC, Li J, Halgamuge SK. CoNVEX: copy number variation estimation in exome sequencing data using HMM. BMC bioinformatics. 2013;14(Suppl 2):S2.

Vijayarangakannan P, Fitzgerald T, Joyce C, McCarthy S, Hurles ME. Detection of Copy Number Variantion from Exomes in the DDD and UK10K Projects. 2012.

Zhang, J. D., Ruschhaupt, M., & Biczok, R. (2013). ddCt method for qRT–PCR data analysis.

Guo Y, Sheng Q, Samuels DC, Lehmann B, Bauer JA, Pietenpol J, et al. Comparative study of exome copy number variation estimation tools using array comparative genomic hybridization as control. BioMed research international. 2013;2013.

Arikawa E, Sun Y, Wang J, Zhou Q, Ning B, Dial SL, et al. Cross-platform comparison of SYBR® Green real-time PCR with TaqMan PCR, microarrays and other gene expression measurement technologies evaluated in the MicroArray Quality Control (MAQC) study. BMC genomics. 2008;9(1):328.

McCoy E, Street S, Taylor-Blake B, Yi J, Edwards M, Wightman M, et al. Deletion of ENTPD3 does not impair nucleotide hydrolysis in primary somatosensory neurons or spinal cord. F1000Research. 2014;3.

Hu C, Zhang R, Yu W, Wang J, Wang C, Pang C, et al. CPVL/CHN2 genetic variant is associated with diabetic retinopathy in Chinese type 2 diabetic patients. Diabetes. 2011;60(11):3085-9.

Exome Aggregation Consortium (ExAC), Cambridge, MA (URL: http://exac.broadinstitute.org) [Accessed May 2015]

Downloads

Published

2016-12-19