To determine the frequency of thiopurine methyltransferase (TPMT) low-activity alleles in the Greenlandic and Danish populations.
142 Greenlandic individuals and 200 Danish blood donors were screened for the TPMT G460A and A719G low-activity alleles.
Thiopurine methyltransferase low-activity alleles were significantly higher in the Greenlandic compared to the Danish population, being 8.1% (95% CI 4.9-11.3) and 3.5% (95% CI 1.7-5.3) (p