## 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:

- Fragment - gaps between the contigs of a draft clone. (In this context, a contig is a set of overlapping sequence reads.) These are represented by 100 Ns in the assembly, whether or not there is bridging information.
- Clone - gaps between clones in the same map contig. These are represented by 50,000 Ns in the assembly if the gap is bridged or 100,000 Ns if it is not.
- Contig - gaps between map contigs. These are represented by 200,000 Ns in the assembly.
- Heterochromatin - gaps from centromeres (3,000,000 Ns) or other large blocks of heterochromatin (size varies).