A total of 62, 7, and 0 references were identified in the PubMed
searches for Bar, Barnase, and Barstar proteins respectively, using
keywords of “allergen” or “allergy” as well as the source organism
names. No references were identified that indicated evidence of
allergy of the Bar protein or the presence of allergens in the
S. hygroscopicus or B. amyloliquefaciens that could indicate potential
safety concerns. The majority of references for bar gene were
related to detection methods, use of as selection marker in developing
transgenic plants, horizontal gene transfer, effect of viral
pathogen infection in plant on transgene expression. One reference
was identified searching with barnase and allergy that was specific
for occupational sensitization to fungal enzymes among workers in
the feed industry. Tests had been conducted using extracts of fungal
organisms. Nine percent of subjects tested positive and were more
frequently sensitized to phytase from Trichoderma sp. and Peniophora
sp., but therewas no description of IgE or allergy to extracts
or proteins from the gene source, bacterium Bacillus amyloliquefaciens
(Caballero et al., 2007).