Imprinted genes are associated with fetal growth and development.
Thus, some imprinted genes are expressed from the paternally inherited chromosome and others from the maternally inherited chromosome.
In contrast to their imprinted expression in mouse, these genes are expressed biallelically in human from early trophoblast through to term.
A characteristic of imprinted genes analysed to date is the presence of allele-specific methylation, a feature that may be used in their identification.
Most autosomal genes are expressed biallelically, but some are imprinted, expressed only from one parental allele.
The evidence for the contribution of imprinted genes is summarized in the previous section.
All other imprinted genes in this cluster are paternally repressed, some ubiquitously and others in the placenta.
They almost invariably have caused widespread social damage, which is imprinted in the psychology of future generations.
