NCBI provides an up to date, comprehensive resource of human genome data, including assembled sequence contigs that are ordered across the chromosome, and linked in multiple ways to cytogenetic, genetic, and physical maps. This includes the standard cytogenetic ideogram, FISH mapped clones, STS maps, several different genetic recombination maps, several RH maps, cytogenetic maps of genes and diseases, as well as transcripts, UniGene clusters, and predicted genes on the contiged assembly.

NCBI provides interactive web tools for specific queries, but also the ability to download subsets of correlated data from any region of the chromosome specified in any of the coordinate systems (cytogenetic, base pair, cM, cR, etc). In addition, the full data set is updated regularly and available for bulk ftp. This tutorial is a detailed discussion of the data, how it is constructed, and examples of how to use it to ask biological and biomedical questions of the human genome.