Microsatellite markers are short repeated DNA sequences. The number of repetitions varies widely, depending on the species, the individual, and even the allele. Since they are found throughout the genome and are highly polymorphic, they are ideal for genetic mapping.
Genotyping on the DNA Analyzer 3730 XL allows the analysis of DNA fragments labeled with a fluorochrome ranging from 60 to 1200 base pairs. There are several multicomponent matrices available for analyzing different types of fluorochromes.
Here are those available at the platform:
DS-33 Matrix Standard Kit (Dye Set G5): 6-FAM™, VIC™, NED™, PET™, and LIZ
DS-36 Matrix Standard (Dye Set J6): 6-FAM™, VIC™, NED™, SID™, TAZ™, and LIZ
Depending on the matrix used, it is possible to automatically analyze 4 to 5 fragments labeled with a different fluorochrome in a single capillary. The same fluorochrome can also be used more than once when the fragments differ by more than 100 base pairs. This allows us to multiplex up to 12 markers per individual in a single sample.
Technique
Genotyping of microsatellite markers is done through PCR amplification. These polymorphic regions are amplified by labeling one of the primers with a fluorochrome. Then, through capillary electrophoresis, it is possible to determine the exact length of each microsatellite studied in an individual.
Applications
- Genotyping of different microsatellites (MicroSAT)
- Human cell line identification – Globalfiler 24 STR Kit
- HLA – Sequencing
- Microsatellite instability – TrueMark MSI Test
- Examination of the 3D structure of nucleic acids – QuShape