Aim:Neural tube defects (NTDs) are serious congenital malformations of the brain and spine. Radiation may induce genetic or epigenetic changes, such as abnormal brain growth, abnormal embryological development, and tumorigenesis. This study investigated the effect of different therapeutic radiation doses on chick embryos on the prevalence of NTDs and bone morphogenetic protein (BMP) 4 and 7 expression levels.Material and Methods:The chick embryos (N = 143) were derived from fertile, specific pathogen-free eggs of domestic fowl. The presence of NTDs was analyzed using a stereomicroscope, and BMP4 and BMP7 expression levels were assessed by immunohistochemical staining. The chick embryos were divided into five groups: control (no radiation exposure) (n = 23), thorax computerized tomography (CT) exposure (n = 30); abdominopelvic CT exposure (n = 30), cranium CT exposure (n = 30), and brain perfusion CT exposure (n = 30).Results:The prevalence of NTDs and BMP4 and BMP7 expression levels in the different groups were compared. In the cranium CT dose group, both the NTD prevalence (20%, p = 0.002) and BMP7 (p = 0.031) expression levels were significantly higher than those in the other groups. However, none of the medical doses of irradiation altered BMP4 expression levels (p = 0.242). No NTDs were detected in the thorax CT and abdominopelvic CT groups. Conclusion:Exposure to irradiation at cranium CT doses may induce the development of NTDs and increase BMP7 expression. Dose radiation exposure using thorax CT and abdominopelvic CT protocols does not appear to induce NTDs.