Optimization of an automated DNA purification protocol for neonatal screening

Context.--Collection of blood from newborns is a standard clinical procedur e used for genetic screening. Typically, blood from a heel prick is absorbe d onto standard collection paper and dried before analysis of metabolites, proteins, hormones, and more recently DNA. Objective.--To evaluate strategies to purify DNA for use with automated wor kstations. Design.--Two factors were used to evaluate several DNA purification protoco ls: residual heme contamination and amplification yield. The protocol that produced DNA with the lowest heme content;and the highest amplification yie ld was selected. In combination with those two performance factors, the pro tocol with the fewest number of steps was chosen to reduce reagent use and processing time. Setting.--Industrial research and development laboratory. Results.--Robust amplification of DNA isolated from dried blood spots was d emonstrated using both fluorescence and agarose gel-based detection methods . In addition, the samples had consistent DNA volumes and had no detectable cross-contamination Suggested instrument settings, equipment, and supplies were included for automated processing of DNA from dried blood spots. Conclusion.--A 4-step DNA processing, protocol was developed for dried bloo d spots. The protocol could be performed in either a manual or automated fo rmat, making it possible to process hundreds of samples in 1 day.