Along with the now recognized dominant role of PfCRT, P. falciparum MDR protein 1 (PfMDR1) is now thought to only modulate cross-resistance patterns in CQR parasites (see later). Meaning, this transporter modifies the rank order of resistance to other drugs such as MQ [58, 59] . Other proteins, including PfNHE1, which is a true NHE, are now suspected to complement drug resistance even further [52, 60] . This degree of genetic complexity involving at least three membrane transporter genes is daunting, but is to be expected. Early explanations for MDR phenomena in either tumor cells, bacteria or parasites were (in hindsight) a bit too optimistically reductionist.