The Array CGH is a tool for monitoring cell lines to analyze the cellular genome in order to identify gains and losses of genetic material with higher resolution than conventional karyotyping.
Why study genetic stability?
As the literature indicates, extended cell culture may lead to the acquisition of genomic abnormalities in the cells. These chromosomal aberrations may have important consequences for the survival, proliferation capacity and differentiation potential in cultured cells, so a monitoring genomic stability of cell lines used in research and therapeutic developments is recommended.
Advantages over conventional techniques:
- Higher resolution over conventional karyotypes with resolution of 5 - 10Mb, the CGH arrays allow the detection of genetic alterations to a 150kb resolution. Two levels of resolution: 750K array and high resolution array.
- Always brings results. Classic karyotypes require crops that can be studied at metaphase and growth failure may give inconclusive results. CGH arrays requiring only the genetic material without requiring a growing crop.
Advantages over other arrays:
Arrays + SNPs oligonucleotide probes allow detection of other abnormalities not only detected with oligonucleotide probes as:
- polyploidy situations: triploidy, tetraploidy, etc.
- Clonal abnormalities or mosaicism above 15%.
- Existence of two identical chromosomes.
- LOH rich regions (appear increased in cell lines with oncologic disorders).