On relative viability and replacement

Journal Article · Sun Sep 01 04:00:00 EDT 1963 · Proceedings of the National Academy of Sciences of the United States of America

DOI:https://doi.org/10.1073/pnas.50.3.514· OSTI ID:4618729

Wallace, B.

A type of replacement exists that could seriously alter the outcome of studies on the viability of irradiated x chromosomes. Conditions under which the replacement could occur were defined, and a search was made for this kind of replacement by comparing the number of Drosophila melanogaster of various genotypes emerging in comparable lethal and nonlethal cultures. Approximately 5,000 control and irradiated x-chromosomes were tested. Levels of radiation used were 500, 1000, and 2000 r of x rays. A total of 77 lethals were recovered among irradiated cultures, for which 77 nonlethals were chosen for comparative analysis. lt was found that heterozygous females carrying an irradiated chromosome do not possess a unique replacement ability. Lethal heterozygotes have somewhat impaired viabilities, but there is no evidence in this data that replacement of the sort that causes spurious ratios occurs in the tests involving the x-chromosome. Evaluations are made of suggestions on experimental data interpretations.

• Research Organization: Cornell Univ., Ithaca, N.Y.
• Sponsoring Organization: USDOE
• NSA Number: NSA-17-040601
• OSTI ID: 4618729
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America, Journal Name: Proceedings of the National Academy of Sciences of the United States of America Journal Issue: 3 Vol. 50; ISSN 0027-8424
• Publisher: National Academy of Sciences, Washington, DC (United States)
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
CHROMOSOMES
DROSOPHILA
DROSOPHILA MELANOGASTER
GENETICS
INSECTS
IRRADIATION
LETHAL DOSE
RADIATION DOSES
RADIATION INJURIES
RECOVERY
REGENERATION
STANDARDS
SURVIVAL TIME