TLR3 and acrodermatitis enteropathica: Relevant genetic deficiencies; in support of this hypothesis, one published study showed that 5% of patients with HSV encephalitis have a specific deficiency in the gene encoding toll-like receptor 3, which plays an important role in innate immune pathways, and 66% of patients with toll-like receptor 3 deficiency later develop AE.[9] 6.