Gene amplification is the increase in copy number of a particular piece of DNA and is a hallmark of tumor cells. Amplified genomic segments are frequently manifested in one of two cytologically recognizable forms. Double minutes are extrachromosomal segments of amplified DNA. Homogeneously staining regions are amplified intrachromosomal segments forming large genomic regions. Some strategies of pharmaceutical research in cancer prevention and treatment could involve curbing cancer development via restricting gene amplification. The first step towards achieving this is to discover the rules that govern whether an amplification event is a double minute or a homogenously-staining region.
It's known that regions of chromosomes that are prone to amplification have palindromic sequences of DNA, which are weak places where the chromosome can break. These palindromic sequences can be naturally found in human genome. The distribution of such sequences can vary from one individual to another. Researchers at the Georgia Institute of Technology have discovered that a particular type of DNA break, a hairpin-capped double strand break, induced by these palindromic sequences, is a precursor to amplification.
"We have a developed a system in yeast which would mimic the situation in human cancer cells wherein oncogenes might be located next to palindromic sequences. Using this system we have discovered the rules tha
'"/>
Source:Georgia Institute of Technology