Send to

Choose Destination
Hum Mol Genet. 2009 Apr 15;18(R1):R60-4. doi: 10.1093/hmg/ddp071.

Lessons learnt from large-scale exon re-sequencing of the X chromosome.

Author information

Cambridge Institute of Medical Research, University of Cambridge, Cambridge, UK.


A candidate gene approach to identifying novel causes of disease is concept-limiting and in the new era of high throughput sequencing there is now no need to restrict the experiment to a few interesting genes. We have recently completed a large-scale exon re-sequencing project using Sanger sequencing technology to analyse approximately 1 Mb of coding sequence of the X chromosome in probands from >200 families with various forms of intellectual disability. We review the lessons learnt from this experience. Comparing large data sets will certainly reveal pathogenic mutations in genes that were not possible to identify previously. However, the task of distinguishing pathogenic mutations from rare sequence variants is not easy and is the most substantial challenge to the next decade. High-throughput technology has the attraction of being cheap, fast and comprehensive but for projects that require detailed coverage of a genomic region at an exhaustive level they may require a combination of large-scale with a small-scale follow-up of difficult regions to sequence. The number of rare truncating variants present in coding regions of the X chromosome that are not pathogenic was 1%. The importance of the quality of the starting material both clinically and molecularly and the number of sequence variants both rare and common that any one individual has across their coding sequence is discussed.

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Silverchair Information Systems Icon for PubMed Central
Loading ...
Support Center