While tumor suppressor properties of BRCA1 are well documented, less i
s understood concerning the normal function of this protein in healthy
adult tissues. We demonstrate here that BRCA1 protein is expressed in
human buccal cells. Expression of BRCA1 mRNA transcripts in buccal ce
lls was confirmed by PCR of reverse transcribed RNA. Three BRCA1 antib
odies, D20, MS110 and MS13, reacted positively with cytospin deposited
buccal cells, demonstrating apparent cytoplasmic and nuclear distribu
tion of BRCA1 protein. Double antibody immunofluorescent, binding of D
20 and MS 110 was differentially distributed. We conclude that buccal
cells provide a cell source for exploration of BRCA1 protein function
in normal human adults.