About SuperBLOK™
What is Cot-1 DNA?
Cot-1 DNA is named from CoT, which stands for Concentration × Time, and it refers to how quickly DNA reassociates or renatures after being denatured.
Cot-1 DNA is designed reduce non-specific binding of probes to the repetitive DNA elements. Probes used in hybridization workflows often contain interspersed repetitive sequences (IRS), which can lead to unwanted, widespread hybridization signals across the genome. To ensure the probe binds specifically to its intended chromosomal location, it is denatured in the presence of surplus unlabeled Cot-1 DNA.
Cot-1 DNA acts as a blocking agent to background noise/interference—why it is also called blocking DNA. In these hybridization workflows, the interaction between Cot-1 DNA and the sample DNA leaves only unique sequences of the probe single-stranded and available for hybridization, which improves accuracy of results.
SuperBLOK™
SuperBLOK™ is the Cot-1 fraction derived from the total genomic DNA extracted from male birth human placenta. It is manufactured by melting, sizing, reannealing, in a controlled process that enriches the fraction of highly repetitive sequences.
The proprietary enrichment process ensures optimal size and performance. It is highly enriched with Alu and Kpn families of repetitive sequences.
What are some applications of SuperBLOK™?
SuperBLOK™ DNA ideal for chromosomal in situ suppression hybridization (CISS), fluorescence in situ hybridization (FISH) comparative genomic hybridization (CGH), and microarray applications. SuperBLOK™ DNA is ideally used as blocking agent in Fluorescent In-situ Hybridization assays and all other applications where DNA hybridization is a critical step.
Fluorescence in Situ Hybridization (FISH)
Cot-1 DNA is included during probe hybridization in FISH assays to block repetitive DNA sequences that are abundant in the genome. By competitively binding to these repeats, Cot-1 DNA reduces nonspecific background fluorescence, allowing clearer visualization of specific chromosomal loci.
Chromosomal In Situ Suppression (CISS) Hybridization
CISS is a specialized FISH technique that relies heavily on Cot-1 DNA to suppress hybridization of repetitive elements in chromosome spreads. This enhances the signal-to-noise ratio, helping probe sequences hybridize specifically to unique DNA regions rather than repetitive ones.
Comparative Genomic Hybridization (CGH)
In CGH, Cot-1 DNA is used during hybridization to suppress repetitive DNA from both test and reference genomes. This ensures that differences in copy number are detected in unique sequences rather than masked or confounded by repetitive sequence binding.
Southern Blotting
When probing genomic DNA in Southern blots, Cot-1 DNA can be added to the hybridization mix to reduce background noise caused by probe binding to repetitive elements. This improves the specificity of signal detection for unique gene sequences.
Microarray Technologies
CGH is a molecular cytogenetic technique used to detect and map changes in DNA copy number across the genome. It compares the DNA of a test sample (e.g., tumor) with a reference sample to identify chromosomal gains, losses, or amplifications.
Target Enrichment Prior to Next-Generation Sequencing (NGS)
During capture-based target enrichment protocols, Cot-1 DNA is often used to prevent probes from binding repetitive genomic elements. This increases the efficiency of enrichment for unique exonic or targeted regions, thereby improving sequencing depth and reducing off-target reads.
This product is for RESEARCH USE ONLY. For manufacturing uses, please contact us.
SuperBLOK™ is a trademark of MBI/GROWCELLS, Inc.
*Cot-1™ DNA is a registered trademark of Life Technologies, Inc.
Certain technologies and/or their methods of preparation, analysis or use may be covered by patents or other intellectual property rights held by others in certain countries. MBI does not encourage or support the unauthorized or unlicensed use of any technology. Use of SuperBLOK™ is recommended only for technology for which the end-user has a license under proprietary rights of third parties or for technology for which a license is not required.
Limited Product Warranty: This warranty limits our liability to replace this product. No other warranties of any kind express or implied, including without limitation, implied warranties or fitness for a particular purpose, are provided by MBI/GROWCELLS, Inc. MBI shall have no liability for any direct, indirect, consequential, or incidental damages arising out of use, or the inability to use this product.