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Chromosomal Aberrations in Blood Lymphocytes of Astronauts (99-E010)
Principal Investigator
Research Area:
Cell and molecular biology
Radiation biology
Species Studied
Scientific Name: Homo sapiens Species: Human

While in Earth orbit, crewmembers are constantly exposed to radiation of solar and galactic origin. Space radiation consists of electrons, protons, heavy particles, single particles of high energy (HZE particles) and secondary radiation, such as bremsstrahlung, neutrons and charged particles created by interactions of primary radiation with nuclei of spacecraft shielding material or the human body. The dosage of each radiation type depends largely on the altitude and inclination of the spacecraft's orbit, effectiveness of the shielding, and solar activity during the mission.

Previous investigations on bacteriophages, bacterial spores, yeast, plant seed, insect embryos, rats, and mice have shown serious effects such as chromosomal damage, cell death, or malfunctions caused by HZE particles passing through the biological material. Irrespective of their rarity, HZE particles represent a considerable risk for humans in space.

The specific effects of HZE particles in humans are not well documented. In ground-based experiments it has been proven that HZE particles induce chromosomal aberrations in human lymphocytes. Thus, this investigation studied chromosomal aberrations in human blood lymphocytes to assess the mutagenic potential of space radiation in man.

Previous investigations were conducted by the same investigator team, using blood from eighteen astronauts and cosmonauts flown on board the Space Shuttle and Mir Space Station. Throughout the study, a postflight increase of chromosomal aberrations in lymphocytes was evident for the long-duration crewmembers. Lymphocytes collected from astronauts and cosmonauts who stayed more than 100 days in Earth orbit showed elevated frequencies of dicentric chromosomes, a typical chromosomal aberration induced by ionizing radiation. In difference to these previous investigations, new multi-color banding fluorescence in situ hybridization (mBAND) and multi-color fluorescence in situ hybrididization (mFISH) techniques were used to analyze the samples.

The compilation of results should provide information about chromosomal aberrations in peripheral lymphocytes of crewmembers exposed to space radiation. The results will enable a better assessment of the genetic risk of humans in space and in consequence, will help to optimize radiation shielding. The data also allows for calculations of aberration frequencies expected during deep-space missions.

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Durante M et al. Chromosome aberration dosimetry in cosmonauts after single or multiple space flights. Cytogenetic and Genome Research. 2003;103(1-2):40-46.[]

Greco et al. Biological dosimetry in Russian and Italian astronauts. Advances in Space Research. 2003; 31(6):1495-1503. Adv Space Res. 2003;31(6):1495-503.[]

Hortsmann M, Durante M, Johannes C, Obe G. Chromosomal intrachanges induced by swift iron ions. Advances in Space Research. 2005; 35(2):276-279. []

Johannes C, Horstmann M, Durante M, Chudoba I, Obe G. Chromosome Intrachanges and Interchanges Detected by Multicolor Banding in Lymphocytes: Searching for Clastogen Signatures in the Human Genome. Radiation Research. 2004; 161:540-548.[]

Obe, et al. Chromosomal aberrations: formation, identification and distribution. Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis. 2002; 504(1):17-36.[]

Chromosome aberrations
Radiation effects
Cell division
Chromosome banding
In situ hybridization, fluorescence

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Data Information
Data Availability
Archive is complete. Data sets are not publicly available but can be requested.
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Chromosomal aberration

Mission/Study Information
Mission Launch/Start Date Landing/End Date Duration
Expedition 10 10/13/2004 04/24/2005 193 days
Expedition 11 04/14/2005 10/10/2005 179 days
Expedition 6 11/23/2002 05/03/2003 161 days
Expedition 7 04/25/2003 10/27/2003 185 days
Expedition 8 10/18/2003 04/29/2004 195 days
Expedition 9 04/18/2004 10/23/2004 188 days
STS-114 07/26/2005 08/09/2005 14 days
STS-115 09/09/2006 09/21/2006 12 days
STS-121 07/04/2006 07/17/2006 13 days

Additional Information
Managing NASA Center
Johnson Space Center (JSC)
Responsible NASA Representative
Johnson Space Center LSDA Office
Project Manager: Pamela A. Bieri
Institutional Support
Deutsche Agentur fur Raumfahrt- Angelegenheiten (DARA)
Alternate Experiment Name
DSO 637
Proposal Date