PlentiPlex™ MSI assays are intended for in vitro diagnosis of impaired DNA mismatch repair system (MMR) affecting prognosis and selection of treatment in cancer patients. PlentiPlex™ MSI assays offer two different multiplexed MSI assays for the length analysis of five micro-satellite loci. The mono- and di-nucleotide panel recommended by the Bethesda guidelines and, the Pentaplex mono-nucleotide panel introduced by Hamelin, enabling evaluation of MMR status on DNA sequencer instruments.
Micro-satellites are genetic motifs consisting of short (one to six bases) nucleotide sequences repeated up to 100 times. During replication, these sequences are susceptible to errors, deletions and insertions, normally corrected by the DNA mismatch repair system. Uncorrected micro-satellite errors are commonly referred to as micro-satellite instability, MSI.
Two examples of microsatelitte instability samples. The tumor tissues (bottom) is compared to non-tumor tissues (top). Shown is capillary gel migration charts with MSI peaks marked with red brackets.
| MSI Hamelin's Panel loci identification | |||
|---|---|---|---|
| Marker | Detected in channel | Label | Average size (bp) |
| BAT25 | Blue | PentaGreen | 120 |
| BAT26 | Red | PentAltRed | 124 |
| NR-21 | Green* | PentAltYellow | 103 |
| NR-22 | Blue | PentaGreen | 142 |
| NR-24 | Green* | PentAltYellow | 132 |
| *Risk of crosstalk between green and yellow channel, so that green signal can be observed in yellow channel. | |||
| MSI Bethesda Panel loci identification | |||
|---|---|---|---|
| Marker | Detected in channel | Label | Typical size range (bp) |
| BAT25 | Blue | PentaGreen | 121-127 |
| BAT26 | Red | PentaAltRed | 122-128 |
| D2S123 | Blue | PentaGreen | 197-227 |
| D5S346 | Yellow | PentAltOrange | 96-132 |
| D17S250 | Green* | PentAltYellow | 147-169 |
|
*Risk of crosstalk between green and yellow channel, so that green signal can be observed in yellow channel. |
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