Vitamin B12 treatment reduces mononuclear DNA damage

Background: DNA damage effects of vitamin B-12 deficiency were performed in vitro and in adults. Methods: The study group included 32 children (13 girls, 19 boys) with vitamin B-12 deficiency (mean age 44 1 58 months) and their 27 mothers (mean age 30.4 +/- 5.3 years). The control group contained 30 healthy children and 25 mothers. DNA strand breaks in peripheral blood mononuclear leukocytes were assayed by single-cell alkaline gel electrophoresis (comet assay) before and 8 days after the first injection of vitamin B-12. Results: Mean DNA damage scores in children with vitamin B-12 deficiency and their mothers were significantly higher before treatment than those after treatment. The DNA damage scores of children after treatment were still significantly higher than controls. There were significant negative correlations between the children and their mothers in terms of vitamin B-12 levels and DNA damage scores (r = 0.3, P = 0.02; r = 0.58, P = 0.002, respectively). There were correlations between the children's and their mothers' DNA damage and the severity of vitamin B-12 deficiency, suggesting that the children and their mothers may play a role in the scarcity of nutritional vitamin B-12. Conclusion: DNA damage is increased in children with vitamin B-12 deficiency and in their mothers. DNA damage scores were significantly improved through vitamin B-12 therapy 8 days after the first injection, however, they were still significantly higher than those of controls.