Yes. It is used in LCR (ligase chain reaction) and LDR (ligase detection reaction). In general a single base change can be detected by two probes that meet with the terminal base of one probe pairing with the base being analyzed. If the terminal base pairs with the template, ligase can join the two probes. If the terminal base does not pair, ligase will not join the probes. Since the ligase is thermostable the reaction can be cycled and the ligation products amplified.