## Description

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

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 two types of gaps:

- Fragment - Gaps that are covered by read pairs. The approximate gap size is known and varies in length.
- Contig - Gaps between unordered and/or unoriented contigs. The gap size is not known and is set to a default of 250 bases for chrU and to a default of 1000 bases for all other chromosomes.