No abstract

SUMMARYProduction of circulating interferon (IFN) was measured in inbred mouse strains following intravenous injection of herpes simplex virus type 1 (HSV-1). IFN titres reached maximal levels 2 to 3 h after injection of virus and a 10-fold difference was found between C57BL/6 mice and BALB/c, as high and low producers respectively. Mendelian analysis revealed that HSV-induced IFN production is governed by several loci, one of which is X-linked. The strain distribution pattern obtained from results in recombinant inbred lines and the results obtained in the congenic B6-C-H-28c-If-11 strain furthermore indicated an absence of close linkage to If-1. It is concluded that the levels of HSV-induced early IFN production are influenced by several autosomal loci and one X-linked locus.

Southern blot analysis with a murine interferon-alpha2 (MuIFN-alpha2) cDNA probe revealed restriction fragment polymorphism of EcoRI- and HindIII-digested C57BL/6 and BALB/cDNA. The inheritance pattern of this polymorphism was examined using DNA from each of the seven recombinant inbred strains derived from C57BL/6 and BALB/c; the strain distribution pattern suggests linkage of INF-alpha genes to two histocompatibility loci on chromosome 4. Southern blot analysis of DNA from six bilinear congenic strains carrying different fragments of the BALB/c chromosome 4 on a C57BL/6 background showed linkage of IFN-alpha genes to the histocompatibility locus H-15. It can therefore be concluded that the IFN-alpha gene cluster is situated on chromosome 4 near the H-15 locus, between loci Mup-1 and b.