Effect of Fast Neutrons on Different Stages of Spermiogenesis in Drosophila melanogaster

Abstract

FROM X-ray studies, it is known that the rates of chromosome aberrations vary with the age of the males¹ and the time from irradiation to insemination². Lüning³ showed that these variations were due to differences in the rates of chromosome breaks in different stages of Spermiogenesis and that in spermatids there was a higher rate than in mature spermatozoa. After Baker and Von Halle's⁴ observation that there was a difference in the rate of dominant lethals in sperm between the first and second day, this was further studied by Lüning⁵ on other types of aberrations. He proposed that this difference was due to a difference in the rate of breaks in ‘mature’ (the first-day) and ‘near mature’ (the second-day) sperm. This conclusion ought, however, to be revised as some yet unpublished experiments have shown.