Genomic Database Search Tools

Search by Feature

Allows users to search the non-B DB DAS by feature. In nonbDAS, for example, a feature is defined as any of the following: a-phased repeat, direct repeat, G-quadruplex motif, inverted repeat, mirror repeat, and left-handed Z-DNA. To learn more about how these features have been identified, click here. Other DAS such as ncbiDAS, abccDAS, and mappingDAS have several features.

Search by Feature Attributes

Allows users to search the non-B DB by feature attributes such as length of loop, stem, score, etc. For example, users can find all the quadruplexes with length greater than 20 bp.

What is DAS?


DAS stands for Distributed Sequence Annotation System.
The five DAS available on the non-B DB are as follows:

DAS Description
abccDAS This database includes features computed at the ABCS including nucleotide tracts and composition, restriction enzyme site, SINE, LINE, splice sites, physical DNA characteristics, gene based synteny blocks (GBSB), etc.
mappingDAS This database includes features remapped to the reference genome using gmap for other data sources such as RefSeq, Ensembl, MGC, Unigene,miRBase etc.
ncbiDAS This database includes features derived from the NCBI genomes directories including genes, exons, introns, CpG islands, SNPs, cytogenic markers assembly information, RepeatMasker elements, etc.
nonbDAS V2.0 (released June 2012) This database includes alternative DNA structure predictions, including Z-DNA motifs, g-quadruplex forming motifs, inverted repeats, mirror repeats and direct repeats and their associated subsets of cruciforms, triplex and slipped structures, respectively.
nonbpDAS V1.0 (released 2010) This database includes alternative DNA structure predictions, including Z-DNA motifs, g-quadruplex forming motifs, inverted repeats, mirror repeats and direct repeats and their associated subsets of cruciforms, triplex and slipped structures, respectively.