Transfer of characteristics from a parent to its offspring is explained in biology. When an adult male and female (of humans) who are displaced from their local environment to another (say, a different continent)for a considerable period of time, conceive and give birth to a baby, the newborn also shows some traits related to the people of the new locality . How is this explained?
Genetic makeup can not vary with the place of conception, but certainly the way genes are expressed can change with change in place of conception. Such changes are called epigenetical changes. Epigenetic change is switching on or off of genes which can be achieved by various method:-
1) DNA methylation
2) Histone modification and
3) RNA associated gene silencing
In theory, change in place of conception, can result in silencing or activation of differential genes in foetus. In fact there is this nice article which discusses how maternal nutrition switches on or off six genes in foetus 1 and . Even stress can cause such epigenetic changes . These environment triggered changes may also result in change of phenotype. For example in mice, the agouti viable yellow (Avy) gene which is a retrotransposon and is found in upstream of the agouti gene. The Avy elements are generally methylated and hence are shut off but in Agouti mouse, they are unmethylated and therefore switched on, which leads to a yellow coat.Though this methylation or unmethylation in agouti mice has not been proved to be a result of environmental factor, but in a strict theoretical sense this can happen (with some or other phenotypic trait)
1] Painter R.C., Roseboom T.J., Bleker O.P. Prenatal exposure to the Dutch famine and disease in later life: an overview. Reproductive Toxicology 20, 345-52 (2005).