Background: Mouse imprinted gene Peg3 encodes a large C2H2 type zinc finger
protein with unique characteristics. Peg3 knockout mice were found to show
an impairment in maternal behaviour of the adult female. Mouse Peg3 is loc
ated on the proximal region of chromosome 7 which is syntenic to the long a
rm of human chromosome 19. It has been reported that a loss of heterozygosi
ty (LOH) of chromosome 19q occurs frequently in several glioma types.
Results: We isolated human PEG3 cDNA. Both human and mouse PEG3 were strong
ly expressed in the adult brain and the Peg3 protein was localized in the n
uclei of both neurones and glial cells. A significant decrease in PEG3 expr
ession was more commonly observed in glioma cell lines as compared with tha
t in primary cultures of astrocytes. Transfection of PEG3 cDNA in a glioma
cell line resulted in a loss of tumorigenicity in nude mice.
Conclusions: The human PEG3 gene is a paternally expressed imprinted gene.
Introduction of PEG3 cDNA into the glioma cells suggests that human PEG3 pr
otein functions as a tumour suppressor. Human PEG3 is located on 19q13.4 an
d is one of the candidates for tumour suppressor genes that are predicted t
o be sited in gliomas.