Analysis of MxA, IL-4, and IRF-1 genes in Filipino patients with subacute sclerosing panencephalitis.

Background: Subacute sclerosing panencephalitis (SSPE) is a chronic and debilitating disease of the central nervous system caused by a latent measles virus infection. Three candidate genes, MxA, IL-4, and IRF-1 genes were shown to be associated with SSPE in Japanese patients. These genes have been suggested to play a role in the establishment of persistent viral infection in the central nervous system. Subjects and Methods: Sixty Filipino SSPE patients and 120 healthy control subjects were included in the study. Single nucleotide polymorphisms at promoter regions (IL-4-590C/T and MxA-88G/T) were screened using PCR-RFLP method. Genotyping was done for GT repeat polymorphism within intron 7 of IRF-1. Results: The TT genotype of MxA, as well as the CT genotype of IL-4, were seen a little more frequently among the SSPE patients as compared to the control subjects. The values though, did not reach statistical significance. IRF-1 analysis did not differ between the two groups. Conclusion: Our study failed to demonstrate a significant association between IL-4, MxA, or IRF-1, and SSPE in the Filipino population. Our results might be explained by a greater contribution of environmental factors such as the socio-economic and nutritional factors in the susceptibility of Filipinos to SSPE other than genetic factors.