Storage: −20°C
UNSPSC Code: 41106310
RIDADR: NONH for all modes of transport
Application:
COT Human DNA is used in chromosome in situ suppression (CISS) hybridization. Cosmid or YAC probes contain repetitive elements that result in monospecific hybridization signals distributed over the entire chromosome. To enable specific hybridization to the chromosomal target site, the probe is denatured together with an excess of unlabeled COT Human DNA as a competitor. COT Human DNA can be used to suppress nonspecific hybridization to human repetitive sequences in microarray analysis, and in filter and in fluorescent in situ hybridization experiments.
General description:
Repetitive elements (IRS) present in a probe (e.g., cosmids, YACs, chromosome painting probes) generate nonspecific hybridization signals that are distributed over the whole chromosome or genome. To enable specific hybridization of the probe to the chromosomal target site (e.g., single-copy sequences or low-copy repeats) the probe must be denatured in the presence of excess unlabeled COT Human DNA. This DNA serves as a competitor. In a subsequent preannealing step, the repetitive probe elements rapidly hybridize to excess repeats in the COT Human DNA, while most of the specific probe sequences remain single-stranded and thus can be hybridized to their chromosomal targets. This technique is known as chromosomal in situ suppression (CISS) hybridization.
Other Notes:
For life science research only. Not for use in diagnostic procedures.
Physical form:
Solution, 1 mg/ml, 10 mM Tris-HCl, 1 mM EDTA, pH 7.4
Sequence:
In agarose gel electrophoresis the length distribution of the COT Human DNA fragments shows a maximum in the range of 50 to 300 nucleotides.