Clustered regularly interspaced short palindromic repeats (CRISPR) are repeat sequences, which are present in the genome of archaea and bacteria. In between these repeats, spacer sequences are present which are derived from the phages.

CRISPR/Cas system is an antiviral defense mechanism that helps bacteria and archaea. The RNAs transcribed from CRISPR array along with the CRISPR associated proteins (Cas) helps in sequence-specific cleavage of the foreign genetic material.

CRISPR/Cas system provides sequence-specific cleavage, which is used to edit the genome of organisms contributing its role in targeted genome editing. Cas9 proteins are endonucleases that make double stranded breaks at the site directed by single guide RNA (sgRNA) or chimeric RNA. By simply designing CRISPR and cas9 constructs any intended site of the genome can be targeted.

Protospacer adjacent motifs (PAMs) are the nucleotide sequences that are required by Cas proteins to recognize target sequence. These can be present either upstream or downstream of the target site.

CrisprGE is a central hub of CRISPR based genome editing. This is a manually curated comprehensive resource containing information of all the genes that are edited by CRISPR/Cas system. It comprises a total of 4680 entries of 223 genes from 32 model and other organisms. Considering potential utilities of CRISPR/Cas system in the vast areas of biology and therapeutics, we foresee that it will serve as a valuable platform for the research community engaged in genome engineering.

Fields covered are as follows: (1) CrisprID (2) Organism (3) Gene/Locus (4) UniProt (5) KEGG (6)Target gene sequence (7) Mutant gene sequence (8) Modification length (9) Genetic modification (10) Location (11) Cell line (12) Method (13) Editing efficiency (14) Promoters (15) conc. sgRNA/Cas9 promoters (16) PMIDs.

There are three tools to help users to analyze their sequences. These are:
A. BLAST CrisprGE: To align their desired sequence with the target sequences from CrisprGE repository.
B. BLAST NTdb: To align their target sequence against the NCBI nucleotide database.
C. CRISPR Mapper: To explore the perfectly matching target sequences from CrisprGE on user provided DNA sequence, which generates a list of target sites with details. This tool can be utilized to find possible off-target sequence regions within particular gene or genome.

Yes, this resource is freely available for to the research community through this Url: http://crdd.osdd.net/servers/crisprge/