Genetic basis for adverse events after smallpox vaccination

Area of Science:

• Pharmacogenomics
• Immunogenetics
• Vaccine Safety

Background:

• Adverse events (AEs) following vaccinia virus administration can occur.
• Identifying genetic predispositions to AEs may allow for pre-vaccination screening.

Purpose of the Study:

• To identify single nucleotide polymorphisms (SNPs) associated with adverse events (AEs) after smallpox vaccination.
• To validate these genetic associations in independent study cohorts.

Main Methods:

• Two independent clinical trials involving healthy adult volunteers receiving the smallpox vaccine.
• Genotyping of 1,442 SNPs and assessment of local and systemic adverse events.
• Statistical analysis to identify SNPs consistently associated with AEs across both studies.

Main Results:

• Three SNPs in two genes, methylenetetrahydrofolate reductase (MTHFR) and interferon regulatory factor-1 (IRF1), were consistently associated with AEs.
• A nonsynonymous SNP in MTHFR showed increased risk of AEs (ORs 2.3-4.1).
• Two SNPs in IRF1 also demonstrated an association with AEs (ORs 3.0-3.2).

Conclusions:

• Genetic polymorphisms in MTHFR and IRF1 are associated with adverse events after smallpox vaccination.
• These findings suggest potential for genetic screening to predict vaccine-related AEs.
• Further research into these genetic markers could enhance vaccine safety protocols.