Imprinted genes

Imprinted genes and the coordination of fetal and postnatal growth in mammals... 

Imprinted genes are shown in bold pl5, postnatal day 15 p5, postnatal day 5. (Adapted from Efstratiadis 1998.)... 

On the other hand, of the 45 or so imprinted genes that have been identified so far, seven have been shown by genetic analysis to have an effect on fetal growth as judged by altered birth weights of pups (Table 2). 

Finally, most of the imprinted genes known to date are expressed and imprinted in the placenta. Other imprinted genes are exclusively imprinted in the placenta but not in the fetus, and these may have a role specifically in placental growth or development (Engemann et al 2000). 

Caspary T, Cleary MA, Perlman EJ, Zhang P, Elledge SJ, Tilghman SM 1999 Oppositely imprinted genes p57(Kip2) and Igf2 interact in a mouse model for Beckwith-Wiedemann syndrome. Genes Dev 13 3115-3124... 

Cattanach BM, Peters J, Ball S, Rasberry C 2000 Two imprinted gene mutations three phenotypes. Hum Mol Genet 9 2263-2273... 

Itier JM, Tremp GL, Leonard JF et al 1998 Imprinted gene in postnatal growth role. Nature... 

Lefebvre L, Viville S, Barton SC, Ishino F, Keverne EB, Surani MA 1998 Abnormal maternal behaviour and growth retardation associated with loss of the imprinted gene Mest. Nat Genet 20 163-169... 

Reik That just shows what the imprinted genes do collectively. 

Raff You have emphasized fetal growth, but you would think that postnatal growth, at least until weaning, would be equally important for this competition. Are there imprinted genes that affect postnatal growth ... 

Regulator of maternally imprinted gene 1166A>C vari- thyroidism type lA (PHP) Bartter s/Gitehnan s to multiple hormones RGS2 maximally (115-118)... 

Dnmtl Maintenance (functions after replication on hemimethylated DNA to restore existing methylation patterns in vitro can methylate non-methylated DNA) associates with histone deacetylase Adult/Embryo DNMTD die in utero DNA in these embryos is hypomethylated, imprinted genes are biallelically expressed ES cells from DNMTl mice are viable and capable of de novo methylation... 

The precise biochemical defect for Prader-Willi syndrome is unknown, but this region of chromosome 15 encompasses an imprinting control center and at least 6 maternally imprinted genes. 

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