The present invention relates to the identification of a specific population of cell types, in particular somatic stem cells including haematopoietic stem cells, mesenchymal stem cells and keratinocyte stem cells. The invention also provides for methods of isolation and uses of the stem cells. Derived from the methods of the present invention, there is provided a method of identifying a stem cell comprising the steps of: obtaining a cell sample including stem cells; detecting the presence of angiotensin converting enzyme (ACE) or a fragment thereof on a cell; and identifying the stem cells having ACE or a fragment thereof.