Fig. 1

Restrictive and prohibitive stem cell policy worldwide. Permissive policy was defined as a policy which specifically permits somatic cell nuclear transfer (SCNT) under certain conditions. Restrictive policy was defined as one which prohibits SCNT, permits the use of hESC research using supernumerary in vitro fertilisation embryos or only permits hESC research on a limited number of lines. Prohibitive policy was defined as one in which research on hESCs or their products was prohibited. Given the differences in policy between federal states in the US, this country was omitted from the calculation of the percentage of countries with restrictive or prohibitive hESC policy. Based on data from the Hinxton Group