Technology Development: Mutation Detection Array

Synopsis

Oligonucleotide microarray DNA chip-based hybridization analysis is a powerful technology with potential for rapid and low-cost screening of all possible mutations and sequence variations in genomic DNA. The project is focused on development and refining of a platform/protocol for screening of disease-causing mutations.

Experimental Overview

The Hybridization-based sequence analysis is carried out with arrays designed to evaluate specific sequences. The method employed in this study is a Gain-of-Hybridization Signal approach, with single colour detection (Fig1). A series of parameters are being considered in the development of the platform, as many factors affect the sensitivity of the technique in the discrimination between normal and mutated alleles (Fig2). The arrays were designed with probes complementary to a subset of mutations in the CFTR gene.

Figure 1: Gain-of-Signal approach results in relative hybridization to allele-specific probes. In this example the target is heterozygous for both G and A residues at the position of interest (J Hacia, nature genetics, vol21, Jan1999)

Figure 2: Example of Hybridization patterns of ΔF508 (CFTR mutation) allelic probes with target DNA: (a) homozygous normal, (b) homozygous affected, (c) heterozygous. No hybridization to negative controls, and no signal from different Target DNA (CS Salvado et al, Reproductive BioMedicine Online, vol8, 17 Nov 2003)

People

Marta Paolucci, Dr Lorne Lonie

To discuss potential collaborative projects please contact: Jiannis Ragoussis