Isolation and sequencing of CA/GT repeat microsatellites from chromosomal libraries without subcloning

A method for the isolation of (CA)n microsatellites from chromosome-specific genomic libraries is described. Clones were first screened using a polynucleotide CA/GT probe. Those shown to contain CA repeats were plaque purified and either subcloned or the insert amplified directly using vector primers. Polymerase chain reaction products were then used to directly sequence the regions flanking CA repeats by using biotinylated primers that amplify cloned inserts outward from CA repeat containing regions of DNA to vector primers. This method provides rapid access to microsatellites from chromosomes or chromosome regions of interest.