A precise and scalable method for querying genes in chromosomal banding regions based on cytogenetic annotations

Motivation: Staining the human metaphase chromosomes revealscharacteristic banding patterns known as cytogenetic bands orcytobands. Using technologies based on metaphase chromosomes,researchers have accumulated much knowledge about the correlationsbetween human diseases and specific cytoband aberrations, indicatingthe presence of disease-associated genes in those bands. Withthe progress of human genome project and techniques such asfluorescent in situ hybridization, many genes have been assignedto the cytobands and annotated in public databases, making itpossible to find all genes in the disease-related cytobandsthrough database queries. However, finding genes in cytobandsremains an imprecise process, partly due to the insufficiencyof current methods for cytoband queries, especially for thosebased on cytogenetic annotations. Results: By transforming the cytoband annotations into numericalsegments, a new query method is developed that is able to accuratelydefine any cytogenetic ranges in human chromosomes. A querysystem (designated cytoband query sys CQS) is implemented usingcytogenetic annotations in the public domain. Judged by a performancetest, CQS executed as accurately as expected using cytogeneticannotations from NCBI Map Viewer. The new method is scalableand can be applied to genomes from other species. Availability: The CQS is freely accessible over the Internetat http://moris.csie.ncku.edu.tw/cqs/ Contact: clh9{at}mail.ncku.edu.tw Supplementary information: http://moris.csie.ncku.edu.tw/cqs/