## Description

This track depicts gaps in the assembly. These gaps - with the exception of intractable heterochromatic gaps - will be closed during the finishing process.

Gaps are represented as black boxes in this track. If the relative order and orientation of the contigs on either side of the gap is known, it is a bridged gap and a white line is drawn through the black box representing the gap.

This assembly contains the following principal types of gaps:

- Clone - gaps between clones in the same map contig. These may be bridged or not.
- Contig - non-bridged gaps between map contigs.
- Centromere - non-bridged gaps from centromeres.
- Telomere - non-bridged gaps from telomeres.
- Heterochromatin - non-bridged gaps from large blocks of heterochromatin.
- Short Arm - non-bridged long gaps on the short arm of the chromosome.

## See also

NCBI discussion of genome assembly procedures.

## Credits

The Feb. 2009 human reference sequence (GRCh37) was produced by the Genome Reference Consortium.