By identifying the responsible genes, it is hoped that they can be transferred into susceptible mosquitos, which transmit malaria parasites to humans. A major gene locus responsible for parasite lysis has been identified on chromosome 3 of Anopheles gambiae encapsulation of parasites in a sheath of melanin . 3 quantitative trait loci have been identified that are responsible for parasite encapsulation.
Nitric oxide is toxic to Plasmodium .
Following infection with Plasmodium , there is an increase in expression of the nitric oxide synthase gene in Anopheles stephensi mosquitos. This gene has recently been sequenced mosquito haemocoel . Many parasites are killed in the mosquito haemocoel before reaching the salivary glands. 22 proteins identified in the midgut of susceptible mosquitos are not found in refractory mosquitos. These proteins may play a role in the susceptibility of mosquitos.