PROTON AND IRON (Fe) ION-INDUCED EARLY AND LATE CHROMOSOME ABERRATIONS IN HUMAN EPITHELIAL AND FIBROBLAST CELLS

摘要

Exposure to radiation in outer space is one of the main concerns for space exploration by humans. Exposure to gamma rays and x-rays can lead to acute and chronic health effects, by focusing deliberately on the works performed on Human Epithelial Cells (HECs) and Fibroblast cells. One approach for evaluating the effects of radiation is collecting human specimens and exposing them to different radiation doses over a specific time frame. Analysis of chromosome aberrations in in Human Epithelial cells and Fibroblasts has been performed after Proton and Fe ions radiation using the fluorescence in-situ hybridization (FISH) technique. FISH technique has proved to be an accurate method for analysis of chromosome aberrations. FISH uses fluorescent probes to detect the position of specific DNA sequences on chromosomes. Exposure to radiation has significant health risk. Radiation induces several types of DNA damages. Unrepaired or wrong repaired DNA can lead to mutations and increase the number of chromosome aberrations. Cells that are susceptible to radiation damages factors are dependent on genomic background and growth. Therefore, cells from different tissues are expected to have different rates of survival. Proton and Iron (Fe) are two of the most abundant types of charged particles in deep space. Both charged particles produce ionization along their path. Protons are called low linear energy transfer (LET) because they are able to pass through matter without losing much energy, like gamma rays and x-rays. Protons have been proven to induce DNA double strand breaks, which are one of the more dangerous DNA lesions, similar to that induced by high-energy irons. Proton and Fe- ions that have been ion induced have been shown to cause DNA damages, DNA damages may consist of deletion, insertion, ring or translocation based on the ionization. Higher levels of Fe radiation found in space is more likely to cause damage to DNA molecules than proton radiation. The wide range variety