Interactions between imprinting effects: summary and reviewCattanach B.M. · Beechey C.V. · Peters J.
Mammalian Genetics Unit, Medical Research Council, Harwell, Didcot (UK)
Mice with uniparental disomies (uniparental duplications) for defined regions of certain chromosomes, or certain disomies, show a range of developmental abnormalities most of which affect growth. These defects can be attributed to incorrect dosages of maternal or paternal copies of imprinted genes lying within the regions involved. Combinations of certain partial disomies result in interactions between the imprinting effects that seemingly independently affect foetal and/or placental growth in different ways or modify neonatal and postnatal development. The findings are generally in accord with the ‘conflict hypothesis’ for the evolution of genomic imprinting but do not demonstrate common growth axes within which imprinted genes may interact. Instead, it would seem that any gene that favours embryonic/foetal development, at consequent cost to the mother, will have been subject to evolutionary selection for only paternal allele expression. Reciprocally, any gene that reduces embryonic/foetal growth to limit disadvantage to the mother will have been selected for only maternal allele expression. It is concluded that survival of the placenta is core to the evolution of imprinting.
Request reprints from Bruce M. Cattanach
Mammalian Genetics Unit, Medical Research Council, Harwell,
Didcot, OX11 0RD (UK)
telephone: +44 1235 841000; fax: +44 1235 841200
Manuscript received: 29 June 2005
Accepted in revised form for publication by F. Ishino,: 24 August 2005.
Number of Print Pages : 7
Number of Figures : 4, Number of Tables : 0, Number of References : 31
Cytogenetic and Genome Research
Vol. 113, No. 1-4, Year 2006 (Cover Date: March 2006)
Journal Editor: Schmid, M. (Würzburg)
ISSN: 1424–8581 (print), 1424–859X (Online)
For additional information: http://www.karger.com/CGR