Genetic variation in the ability of several strains of rats to produce interferon in response to polyriboinosinic-polyribocytodilic acid.

The ability of various strains of rats to produce interferon in response to polyriboinosinic-polyribocytodilic acid was investigated. ACI and DA (RT-1a), BN (RT-1n), Buffalo (RT-1b), August (RT-1c), and GH (RT-1l) strains produced low levels of interferon in response to intraperitoneal administration of polyriboinosinic-polyribocytodilic acid. However, Lewis (RT-1l) rats demonstrated a 20- to 40-fold higher response. The genetic basis of this difference in production was examined through use of F1 and backcross generations of rats. Both (ACI X Lewis) and (Lewis X ACI) F1 rats exhibited levels of interferon production intermediate to those of the parental strains. No maternal or paternal effects were observed. Results with the F1 rats and the wide variation of response also observed in the backcross generations of F1 rats to either low (ACI) or high (Lewis) responders suggested that several loci control the ability of these rats to produce interferon. Compatibility at the RT-1 locus in both low and high responders negates any significant involvement of the major histocompatibility complex in this control.