Stem cell research

Stem cells are cells that can renew themselves over long periods by division and have the capacity to develop into individual or different cell types with specific characteristics (differentiation).  Under suitable conditions all kinds of tissue can potentially be developed from stem cells.  For this reason it is hoped that research on stem cells, coupled with a better understanding of the processes of development and how they may be controlled, may make it possible, by means of cell replacement, to cure diseases due to tissue defects.  Examples of such diseases are neurodegenerative conditions, injuries to the spinal cord, diabetes mellitus, the sequelae of cardiac infarction and various forms of pathology affecting the haematopoietic (blood-producing) system.

Stem cells may be derived either from embryos in the first few days of their development (embryonic stem cells) or from certain tissues taken even from adult subjects (adult stem cells).  It is not yet clear whether embryonic and adult stem cells are equally suitable, in terms of their potential capacity for development and multiplication, for cell and tissue replacement.

Particular ethical problems arise in connection with the derivation of embryonic stem cells because the technique results in the destruction of the embryos.  The production of human embryonic stem cells is prohibited in the Federal Republic of Germany by the Embryo Protection Law.

The permissibility of using embryos for research purposes is a matter of political and social controversy. Although everyone agrees that the protection of human life is a primordial moral and constitutional concern, opinions differ on the protection to which human life is entitled during its early embryonic development.

The stem cells themselves are not embryos within the meaning of the Embryo Protection Law, as the general scientific presupposition today is that these cells are not totipotent but pluripotent - that is, they do not possess the capacity to develop into a human being.  The import and use of embryonic stem cells for research purposes are to be regulated by a Stem Cell Law.

The German National Ethics Council issued its first Opinion, on the import of embryonic stem cells, in December 2001.