- Croatian population data for the C677T polymorphism in methylenetetrahydrofolate reductase: frequencies in healthy and atherosclerotic study groups. Zuntar, I., Topić, E., Vukosavić, D., Vuković, V., Demarin, V., Begonja, A., Antoljak, N., Simundić, A.M. Clin. Chim. Acta (2003)