Identification of Genes and Construction of a Transcriptional Map in Xq28

Abstract

The identification and sequencing of the human genes and their localization on the map of the human genome will provide an invaluable tool to study genetic disorders. It will identify candidate genes for diseases mapped to specific regions of the genome, where gross rearrangements of genomic material cannot be detected and all the genes from a large candidate region need to be isolated and analyzed. Intermediate goals are the development of methods to identify and map genes, and their application to the study of selected regions of the genome. One such region is the human X chromosome which contains many mapped disease loci. However, fewer than 100 X-linked genes have been characterized and cloned, a small proportion of the 3000 to 5000 genes expected on the chromosome (1). The distal portion of the long arm is among the most gene dense portions of the human X chromosome (1). By isolation and mapping of transcripts and CpG islands to the physical map of the region and by determination of partial nucleotide sequences and study of the pattern of expression of the transcripts identified, we are constructing a transcriptional map of Xq28 which should help in the identification of candidate genes for the several uncloned rare disorders localized to this chromosomal band.