Viability mutations induced by the P elements in Drosophila melanogaster.

Abstract
Mutations were accumulated for 9 generations on 53 second chromosomes that originated from a single chromosome. The test of viability for these chromosomes indicates that the P elements induce mainly lethal and severely detrimental mutations. The lethal load induced during 9 generations was approximately 1.5 times as large as that of the equilibrium populations. These mutations did not modify the specific activity of alcohol dehydrogenase. These findings were a sharp contrast to those for the mutations induced by a putative transposon detected in the Osaka population by Mukai and Yukuhiro (1983).