DHFR and infection: Additionally, markers of resistance, such as pfcrt and pfmdr1 [131] for chloroquine and mefloquine resistance, dhfr (dihydrofolate reductase) and dhps (dihydropteroate synthase) for sulfadoxine-pyrimethamine resistance [132], and Kelch13 (K13) for artemisinin resistance [133], reveal information about necessary treatment guidelines as well as the spread of resistant infection.