Cloning and characterization of some rep20 dna fragment from the genome of the human malaria pathogen plasmodiuom falciparum

الملخص EN

The development of chloroquine as an ant malarial drug and the subsequent evolution of drug resistant Plasmodium strains had major impacts on global public health in the 20th century.

In P.

falciparum, the cause of the most lethal human malaria, chloroquine resistance is linked to multiple mutations in PfCRT, a protein that likely functions as a transporter in the parasite's digestive vacuole membrane.

Rapid diagnostic assays for PfCRT mutations are already employed as surveillance tools for drug resistance.

However, several reports have been published demonstrating cases with CO resistance.

Sporadic cases have been reported as well as one large scale study demonstrated 12.4% resis¬tance.

However, all these reports were based on treatment failure (in vivo) ra¬ther than in vitro or molecular bases.

Evidence suggests a crucial role for a point mutation in the P.

falciparum chloroquine resistance transporter ipfcri) gene on chromosome 7 in conferring CQ resistance.

The mutation in the K76 codon in 3 cases out of 60 (5%) using Apol restriction enzyme was detected.

Although the percentage of drug resistance was not quite disturbing, but represented the possible establishment of chloroquine-resistant P.

falciparum in Saudi Arabia, or the beginning of resistant strains by labors coming from abroad.

Cross-border importation of resistant strains from neighboring coun¬tries must be considered.

In vivo tests must be conducted parallel with the mo¬lecular markers to estimate more precisely the actual prevalence of resistance.

Validation of molecular markers is urgently required and needs strong colla¬borative partnerships between sub regional and regional networks.