The importance of these many facets of the innate immune antiviral response are highlighted in observations that patients with tyrosine kinase 2 (TYK2) deficiency, who have impaired type I IFN, IL-6, and IL-12 responses, have increased frequency of recurrent HSV infections (23). This evidence concerns the gene TYK2 and hyperinsulinemic hypoglycemia, familial, 4.