A biometrical genetic analysis of ethanol response in selectively bred Long-Sleep and Short-Sleep mice

A classical Mendelian cross was derived from Long-Sleep (LS) and Short-Sleep (SS) mice, lines selectively bred for differences in response to hypnotic doses of ethanol (ETOH). Biometrical genetic procedures applied to the selection phenotype, namely, duration of the ETOH-induced loss of the righting reflex, suggest that a simple additive genetic system controls this depressant response. Sex differences were present in the Mendelian cross generations that had the longest duration responses. An estimate of the number of loci differentiated by the selection was nine. Blood ethanol levels at the time of regaining the righting reflex in the seven genotypes of the Mendelian cross showed that the selection operated solely by changing tissue sensitivity to ethanol.