Genetic variation in host defenses and viral infections

Conclusions: Recent advances in genomics now permit the analysis of germ-line variation and susceptibility to viral infections. So far, studies have investigated variation in genes of innate immunity, but it is clear that we must look at many pathways in host defenses. While the analysis of HLA, chemokines and cytokine defenses have been fruitful, the next steps require careful assessment of pathways to be analyzed because it is likely that sets of SNPs or haplotypes contribute to outcomes in viral infections. In conclusion, it is now possible to probe the genetic basis of host response to viral pathogens. Rapid progress in the technical and bioinformatic platforms has accelerated the opportunity to examine host-pathogen genomic interactions. Large epidemiological studies are required to adequately study common SNPs in case control or cohort studies addressing viral infections. Since SNP studies generally do identify a highly penetrant variant, follow-up validation studies are critical before implementation in medical care. It can be argued that no SNP study stands alone, but must be replicated to confirm the genetic link between one or more outcomes and the genetic variant(s) of interest.