DNA extraction from dried blood specimen

[benedictine]

hi, I have done pcr on DNA extracted from archive dried blood specimen (filter paper) stored at room temperature; most of the amplification did not work. DNA was extracted using TE-method, add 65ul TE buffer, 50 deg for 15 min, then 97 deg 15 min, centrifuge 2-3 sec. The problem is not with the PCR method because it was also tested on other DNA and that was good.

does anyone have advice for me, how else should I extract the DNA; is it possible that the DNA has degraded (I don't know how old these samples are)? thanks

from Bene