Submitted September 14, 2007
Returned for revision October 8, 2007
Accepted January 30, 2008
Minireview
Heredity -- Venturing Beyond Genetics
Marie-Christine Maurel *
and
Colette Kanellopoulos-Langevin
* To whom correspondence should be addressed. E-mail: maurel{at}ijm.jussieu.fr.
Abstract
Our knowledge of heredity has recently undergone major upheaval. Heredity transmits considerably more than just genetic elements: 1) the oocyte is full of maternal cytoplasmic components subsequently present in each new cell 2) maternal cells are able to pass to the progeny, and they remain active into adult life (microchimerism). Here we examine the notion that the transmission of characters involves at least two processes besides that of Mendelian heredity, long considered to be the only hereditary mechanism. These processes, which all involve epigenetic processes, involve the transmission of macromolecules, subcellular organelles and living cells solely from the mother to her offspring, be they female or male, during pregnancy and lactation. We postulate that cytoplasmic heredity and maternal transmission of cells leading to a long-term state of microchimerism in progeny are two good examples of matrilineal non-Mendelian heredity. A mother's important contribution to the development and health of her progeny seems to possess many uncharted depths.
Key words:
Immunology •
Pregnancy •
Developmental biology •
heredity •
maternal-fetal exchanges
