Expression of cell cycle genes among the residents of settlements along the Techa River exposed to ionizing radiation <i>in utero</i>

Abstract

BACKGROUND: The period of intrauterine development is highly susceptible to the effects of ionizing radiation. While the consequences of radiation exposure during pregnancy are not yet fully understood, it is believed that individuals exposed to ionizing radiation in utero are at a greater risk of long-term health consequences. AIM: To analyze the expression of mRNA of cell cycle genes (TP53, MDM2, CDKN1A, ATM) in individuals exposed during intrauterine development to chronic radiation exposure after the Techa River accident. MATERIAL AND METHODS: The study was conducted over 60–70 years after the onset of chronic radiation exposure in a group of 170 individuals. Among them, 54 individuals were exposed to radiation during both prenatal and postnatal periods of development, while 80 individuals were exposed to chronic radiation after birth. The comparison group consisted of 36 individuals living in similar socio-economic conditions, with a lifetime cumulative dose of red bone marrow radiation not exceeding 70 mGy. RESULTS: Individuals residing in coastal villages along the Techa River, who were exposed to radiation during both the prenatal and postnatal stages of development, experience a reduction in the relative mRNA content of the MDM2 and CDKN1A genes compared to the control group and individuals who were exposed to chronic radiation after birth. The results of the correlation analysis indicate that there is no association between changes in mRNA expression of the studied genes and the accumulated absorbed dose of intrauterine and postnatal exposure of red bone marrow. CONCLUSION: The reduced transcriptional activity of the MDM2 and CDKN1A genes in individuals exposed to chronic radiation in utero may play a role in the development of long-term effects of radiation exposure in humans.