Ionizing radiation is applied in healthcare for diagnostics or cancer therapy in various human populations, including pediatric patients. To ensure children's stillness during radiological procedures, they are usually sedated/anesthetized with anesthetics, such as ketamine. Previous studies have shown that exposure to ketamine, ionizing radiation, or a combination of both during critical periods of brain development can result in cognitive impairment later in life.The purpose of the project is to investigate developmental neurotoxic effects of ketamine and low-dose ionizing radiation.Female NMRI-mice were exposed on postnatal day 10 to ketamine (7.5 mg/kg), low-dose ionizing radiation (200 mGy), or co-exposure. Then, gene expression patterns in hippocampusfor Jagged1, Hes5, Nrf2, Keap1, Bdnf and Grin2b were studied by qPCR.Two primers were designed for the mouse genes Cat, Sod2, Tia1 and G3bp1 respectively. Subsequently, efficiency of each primer was investigated using qPCR to generate a standard curve.The gene expression of Grin2b showed/displayed statistically significant downregulation in all exposed groups. No statistically significant change in the gene expression of Jagged-1, Hes5, Nrf2, Keap1 and Bdnf were observed.Due to appearance of secondary peaks, primers for Tia1:1, G3bp1:2 and Sod2:1 were excluded from the study. The efficiency of Cat1, Cat2, Sod2-2, Tia1-2 and G3bp1-1 did not meet the criteria (90–110%) for further work.Exposure to ketamine, low-dose ionizing radiation or a co-exposure may affect Grin2bexpression in children and consequently result in cognitive impairment. More studies are required to determine the underlying mechanism. Additional aspects to consider when designing primers should be implemented.