DNA elution and amplification by polymerase chain reaction from dried blood spots.

A quick, sensitive and easily automatizable method for PCR amplification of genomic DNA eluted from dried blood spots is described. DNA is eluted from a 3-mm spot routinely used for neonatal screening of inherited diseases either by boiling or by sonication. A preliminary and brief spot-autoclaving step is mandatory to ensure optimal and reproducible PCR amplifications. Only 1% of the eluted DNA is required for PCR analysis allowing the execution of multiple genetic tests on the same blood spot. The method has been successfully applied to the detection of a known phenylketonuria-causing mutation and will facilitate the analysis of the genetic repository provided by Guthrie's cards stored in neonatal screening laboratories.