InSitupedia

 

     In situ hybridization (ISH) is a unique technique that allow specific nucleic acid sequences to be detected in morphologically preserved chromosomes, cells or tissue sections. The method involves a hybridization reaction between a labeled nucleotide probe and complementary target DNA or RNA sequences. In combination with immunocytochemistry, ISH can relate microscopic information to gene activity at the DNA, mRNA and protein level.

 

     

 

This technique was originally described by Pardue, Gall and John in 1969. Since then many variations of ISH methods have been developed. During the past decade, ISH has become and important tool in basic scientific research and clinical diagnosis. Between January 1994 and July 1995, more than 4,000 articles using this technique were published.

 

     

 

Other recent improvements in the applications of ISH involve in situ polymerase chain reaction (PCR) which can be used to detect very low levels of nucleic acids in tissues by taking advantage of the powerful amplification capacity of PCR.