After space flight, astronauts have more DNA abnormalities, which might raise their cancer risk. High-level radiation is the major worry. Cancer risk factors include high radiation exposure.
14 space shuttle astronauts participated. In 1998-2001, they performed 12-day shuttle flights. Astronauts averaged 44 years old. Researchers obtained whole blood samples twice
ten days before flight and on landing—and white blood cells once, three days after landing. These samples were frozen at 112°F for 20 years.
Researchers found astronauts had higher somatic gene mutations than non-astronauts. Somatic mutations occur after conception in cells other than sperm or egg cells, thus they're not handed down
The astronauts' mutations caused clonal hematopoiesis, an overrepresentation of single-clone blood cells. This causes chronic myeloid leukaemia and other blood cancers.
Researchers found 34 mutations in 17 astronaut genes using DNA sequencing and bioinformatics. TP3, a gene that encodes a tumor-suppressing protein, and DNMT3A are often mutated in AML