Genome-wide SNP analysis in cancer: leukemia shows the way.

The application of novel genetic/genomic technologies to the study of acute leukemia has frequently been a proving ground for such approaches in cancer. Recent development of high-resolution single-nucleotide polymorphism (SNP) arrays allows detailed assessment of the genomes in cancer cells. A recent study by Mullighan et al. uses SNP arrays to assess copy number alterations in a large group of childhood acute lymphoblastic leukemias and demonstrates frequent mutation of genes encoding transcription factors important for B cell development. These studies not only provide information about the multistep development of leukemia, but also demonstrate the potential for this approach in other cancers.