Homo sapiens (Graphic courtesy of CBSE)

The February 2009 human reference sequence (GRCh37) was produced by the Genome Reference Consortium. For more information about this assembly, see GRCh37 in the NCBI Assembly database.

Sample position queries

A genome position can be specified by the accession number of a sequenced genomic clone, an mRNA or EST or STS marker, a chromosomal coordinate range, or keywords from the GenBank description of an mRNA. The following list shows examples of valid position queries for the human genome. See the User's Guide for more information.

Assembly Details

The GRCh37 build reference sequence is considered to be "finished", a technical term indicating that the sequence is highly accurate (with fewer than one error per 10,000 bases) and highly contiguous (with the only remaining gaps corresponding to regions whose sequence cannot be reliably resolved with current technology). Future work on the reference sequence will focus on improving accuracy and reducing gaps in the sequence. Statistics for the GRCh37 build assembly can be found on the NCBI Build 37.1 Statistics web page. For a glossary of assembly-related terms, please see the GRC Assembly Terminology page.

Note on chrM
Since the release of the UCSC hg19 assembly, the Homo sapiens mitochondrion sequence (represented as "chrM" in the Genome Browser) has been replaced in GenBank with the record NC_012920. We have not replaced the original sequence, NC_001807, in the hg19 Genome Browser. We plan to use the Revised Cambridge Reference Sequence (rCRS) in the next human assembly release.

Chromosome naming scheme
In addition to the "regular" chromosomes, the hg19 browser contains nine haplotype chromosomes and 59 unplaced contigs. If an unplaced contig is localized to a chromosome, the contig name is appended to the regular chromosome name, as in chr1_gl000191_random. If the chromosome is unknown, the contig is represented with the name "chrUn" followed by the contig identifier, as in chrUn_gl000211. Note that the chrUn contigs are no longer placed in a single, artificial chromosome as they have been in previous UCSC assemblies. See the sequences page for a complete list of hg19 chromosome names.

The nine haplotype chromosomes are:

See the Wellcome Trust Sanger Institute MHC Haplotype Project web site for additional information on the chr6 alternate haplotype assemblies.

The Y chromosome in this assembly contains two pseudoautosomal regions (PARs) that were taken from the corresponding regions in the X chromosome and are exact duplicates:

chrY:10001-2649520 and chrY:59034050-59363566
chrX:60001-2699520 and chrX:154931044-155260560

For further information on GRCh37 build see the NCBI GRCh37 release notes.

Bulk downloads of the sequence and annotation data are available via the Genome Browser FTP server or the Downloads page. We recommend that you use rsync for downloading large or multiple files.

The hg19 annotation tracks were generated by UCSC and collaborators worldwide. See the Credits page for a detailed list of the organizations and individuals who contributed to this release.

Genbank Pipeline Details