Resources are pouring into the vital task of understanding - and eventually controlling - the biochemistry and genetics of stem cell differentiation. Here, ScienceDaily reports on advances relating to blood stem cells: "Blood cell formation, known as hematopoiesis, begins with a [stem cell], which can either 'self-renew' and make more copies of itself or differentiate into either red blood cells, various types of white blood cells, or platelets. The genes that control proliferation and differentiation have been difficult to study using traditional gene disruption methods because loss of genes thought to be critical for this process often results in embryonic death, making it impossible to study the role of the gene of interest in mature animals. [Scientists have] found a way around this problem."

Link: http://www.sciencedaily.com/releases/2005/02/050201193549.htm