Some global specimen collection and handling issues to consider include:
- Specimens that contain nucleated cells will be of interest in DNA methodologies while specimens lacking nucleated cells are more useful in RNA methodologies.
- rRNA is more stable than mRNA, which is labile and sensitive to contamination.
- DNA is relatively stable and can be obtained from nonviable sources.
- Serum or plasma obtained by standard routine venipuncture procedures can be used as long as proper site selection and decontamination occur.
- Standard anticoagulants such as ethylenediaminetetraacetic acid (EDTA) and acid citrate dextrose (ACD) can be used; however, avoid the use of heparin as an anticoagulant as it interferes with some polymerase chain reaction (PCR) methodologies.
- When using fluorescence, fasting serum or whole blood specimens should be used to decrease the interference by lipids.
