Patent ID: 7462448

Claim:
A method for detecting species-specific nucleic acid, comprising: a) providing i) a nucleic acid sample from a culture of cells of a first species, wherein said culture has had previous exposure to a second culture of cells from a second species or a cell product derived from said cells from a second species; ii) first nucleic acid probes specific for nucleic acid from said second species; and (iii) second nucleic acid probes specific for said first species; b) exposing said sample to said first nucleic acid probes under conditions such that said first nucleic acid probes hybridize to nucleic acid from said second species and do not hybridize to nucleic acid from said first species to detect nucleic acid from said second species; and c) exposing said sample to said second nucleic acid probes, wherein said second nucleic acid probes are selected from the group consisting of SEQ ID NO:3 and SEQ ID NO:4, under conditions such that said second nucleic acid probes hybridize to nucleic acid from said first species and do not hybridize to nucleic acid from said second species to detect nucleic acid from said first species.