Oxidative stress and DNA damage profile in cord blood of vitamin B12-deficient newborns

Background: Vitamin B12 is an essential biomolecule involved in DNA synthesis, epigenetic regulation, and energy metabolism. Maternal vitamin B12 deficiency during pregnancy has been linked to oxidative stress and impaired DNA integrity. This study aimed to investigate oxidative stress and DNA damage biomarkers in term newborns with vitamin B12 deficiency and to assess their diagnostic value. Methods: A single-centre, prospective case-control study was conducted in 48 term newborns with vitamin B12 deficiency and 40 matched healthy controls. Cord venous blood samples were analysed for vitamin B12, oxidative stress parameters, and a DNA damage marker. Diagnostic performance was evaluated by receiver operating characteristic analysis. Results: Vitamin B12 levels were markedly lower in the patient group than in controls. Newborns with vitamin B12 deficiency had significantly higher levels of 8-hydroxy-2'-deoxyguanosine, total oxidant status, and oxidative stress index, whereas total antioxidant status did not differ. Receiver operating characteristic analysis demonstrated the highest diagnostic accuracy for total oxidant status, followed by 8-hydroxy-2'-deoxyguanosine and oxidative stress index. Conclusions: Oxidative stress and DNA damage were clearly increased in vitamin B12-deficient newborns. These findings suggest that maternal vitamin B12 deficiency leaves detectable biochemical imprints at birth. This prospective analysis highlights that total oxidant status, oxidative stress index, and 8-hydroxy-2'-deoxyguanosine may serve as valuable diagnostic biomarkers and, to our knowledge, represents one of the few studies linking vitamin B12 deficiency to oxidative damage in newborns.