Abstract:
BACKGROUND : Formalin-fixed paraffin-embedded (FFPE) tissue archives in hospitals, biobanks,
and others offer a vast collection of extensive, readily available specimens for molecular testing.
Unfortunately, the use of tissue samples for molecular diagnostic applications is challenging;
thus, the forensic pathology FFPE tissue archives in Africa have been a largely unexploited
genetic resource, with the usability of DNA obtainable from these samples being unknown.
INTERVENTION : The study, conducted from January 2015 to August 2016, determined the
usefulness of FFPE tissue as a reliable source of genetic material for successful post-mortem
molecular applications and diagnostics. Formalin-fixed paraffin-embedded tissue samples
were collected and archived from autopsies conducted over 13 years in the forensic medicine
department of the University of Pretoria (Pretoria, South Africa). Deoxyribonucleic acid from
FFPE tissue samples and control blood samples was amplified by high-resolution melt realtime
polymerase chain reaction before sequencing. The procurement parameters and fixation
times were compared with the quantity and quality of the extracted DNA and the efficiency of
its subsequent molecular applications.
LESSONS LEARNT : This study has shown that FFPE samples are still usable in molecular forensics,
despite inadequate sample preparation, and offer immense value to forensic molecular
diagnostics.
RECOMMENDATIONS : FFPE samples fixed in formalin for more than 24 h should still be used in
molecular diagnostics or research, as long as the primer design targets amplicons not exceeding
300 base pairs.
