The homozygous polymorphisms of CR1 intron 27 and exon 22 (TT and GG) and alleles (T and G) that are associated with low expression of CR1 on red blood cells, conferred significant protection against CM, MOD and malaria deaths.
The result of the present study which analyzed three SNPs (intron 27 HindIIIA>T, exon 22 3650 A>G, and exon 33 5507 C>G) of the CR1 gene in Orissa, a hyperendemic state in eastern-India showed that a significantly increased risk for cerebral malaria (CM) was associated with AA genotype of both intron 27 and exon 22 when compared with mild, severe malaria anemia (SMA) and CM+SMA group respectively.