NIH Research Festival
Ionizing radiation (IR) is widely employed for medical diagnostic and therapeutic purposes. However, the biological effects of IR from clinically relevant diagnostic doses remain unclear. A novel model using human embryonic stem cell (hESC) cultures was established to conduct our study of IR effects. Since IR is often implicated as a risk for inducing cancer, a primer pool targeting genomic “hotspot” regions that are frequently mutated in human cancer genes was used to generate libraries from four hESC cell lines: H1, H7, H9, and H14. Previously, we successfully detected single nucleotide variants occurring at very low frequencies (≈2%) after exposure to high (1 Gy) doses of gamma irradiation using two independent analysis software platforms, thus confirming the utility of our method. However, no differences in the number of genetic alterations were observed between the low-dose (0.2 Gy) samples and controls. In this study, hESCs were placed in the abdominal cavity of a human phantom and subjected to CT scans. They were then maintained in culture until confluence before harvesting for DNA isolation and library synthesis. Using a semiconductor-based deep sequencing approach, we did not detect any differences in the number of genetic alterations between the CT samples and controls, suggesting that in these highly sensitive hESCs, CT scans did not result in a detectable increase in genetic alteration events occurring within the cancer “hotspot” gene regions. Future studies are warranted to confirm the apparent lack of detectable genetic alterations in hESCs caused by IR from diagnostic imaging procedures.
Scientific Focus Area: Stem Cell Biology
This page was last updated on Friday, March 26, 2021