[Molecular biological detection of tissues of central nervous system in meat products]

In principle, molecular biological methods can be used for the detection of specified risk material (SRM) in meat products. We were able to identify suitable target mRNAs for the marker proteins glial fibrillary acidic protein (GFAP) and myelin basic protein (MBP) of tissues of the central nervous system (CNS). The selected primers for GFAP ("GFAP87") and MBP ("MBP51") facilitated the detection of CNS in non-heated and heated standards of emulsion type (and raw) sausages with defined addition of brain by reverse transcription and polymerase chain reaction (RT-PCR). Stability of the mRNA proved to be given over a minimum of 48 hours. First results indicate an even higher stability of the target mRNAs over time and an ample stability against meat technological influences such as storage, temperature, and ripening. RT-PCR with GFAP87 facilitates the detection of CNS of all relevant slaughter animals in meat products. Thus it can be applied in food labeling control. Using RT-PCR and MBP51 as primer we were able to detect selectively the CNS of bovines, ovines and caprines but not CNS of porcines and poultry. Thus we have a second RT-PCR detection procedure for CNS in meat products which, however, yields results equivalent to the legal definition of SRM. The further development of these molecular biological methods would be of considerable importance for routine food control and reduction of human TSE-exposure risk.