Telomere length, measured from blood cells, is commonly used as the standard telomere length of the whole body. The relationship between blood telomere length and oral telomere length is still unclear, especially among neonates. In this study, we measured blood telomere length as well as cheek cells telomere length to find out the overall telomere synchronization in neonates. Children aged 1 month or younger were included in this study. Blood and cheek cells were collected by heel stick method and nylon brush accordingly. Telomere length was measured by Southern blotting. A strong telomere length correlation (0.77, p < 0.001) existed between oral and blood cells which showing telomere length synchronization among different tissue types. Mean telomere length and length variability were significantly higher (t=3.73, p=0.0004) in oral cells. Longer telomere among oral cells can be justified by progenitor cell pool theory. The cause of high telomere length variability in the oral source is not clear although the presence of leukocytes among cheek cells cannot be excluded. Therefore, for telomere length measurement purpose blood should be given preference over the oral source.

Keywords: cheek cells, neonates, oral cells, telomere length, white blood cells