The European Food Safety Authority (EFSA) received in December 2011, a request from the European Commission for an update of the possible scientific developments of cloning of farmed animals for food production purposes.
The present Statement follows the EFSA 2009 and 2010 Statements and the EFSA 2008 Scientific Opinion, and is based on peer reviewed scientific literature published since the EFSA 2010 Statement, information made available to EFSA following a call for data, and discussions with experts in the field of animal cloning.
Cloning by Somatic Cell Nuclear Transfer (SCNT) in cattle and pigs has produced healthy clones and healthy offspring that are similar to their conventional counterparts based on parameters such as physiological characteristics, behaviour and clinical status. With respect to food safety, there were no indication that differences exist for products (i.e. meat and milk) of healthy clones and their offspring compared with those from healthy conventionally bred animals. Data on clones of farmed species for food production other than cattle and pigs have remained limited and do not allow for the assessment of food safety or animal health and welfare aspects.
Health and welfare were compromised in a proportion of clones, mainly observed as increased mortality within the postnatal and juvenile period of calve and piglet clones, as well as in a proportion of the surrogate dams that were affected by abnormal pregnancies. For cattle and pig clones, epigenetic dysregulation remained the main source of anomalies throughout development. The majority of reports published over the last 2 years covers research to try to overcome this dysregulation. So far, no major breakthroughs have been reported on improved overall cloning procedures that would result in an increase of the SCNT cloning efficiency calculated as the number of live offspring as a proportion of the number of transferred embryos. This efficiency is still in the range of 6-15% for cattle and of 6% for pigs, albeit occasionally higher success rates were reported. If the comparator for cattle cloning is in vitro fertilisation (IVF), the background (i.e. the percentage of live offspring per transferred embryo from IVF) is 45-60% and the efficiency of SCNT when compared to IVF can be calculated as 13-25%.
No new elements have emerged that would change the previous EFSA Opinion on the possible environmental impact of cloning: i.e. cloning in itself of farmed animals poses no particular threats for genetic diversity or biodiversity; and from the limited data available there are no indications that would suggest new or additional environmental risks from farmed animal clones when compared to conventionally bred farmed animals. There is also no information available to suggest that such risk may exist.
No new information has become available since the EFSA 2009 and 2010 Statements and the EFSA 2008 Scientific Opinion that would lead, at this point in time, to a reconsideration of the conclusions and recommendations related to the food safety, animal health and welfare aspects, and environmental aspects of animal cloning of the 2008 Scientific Opinion and the 2009 and 2010 Statements of EFSA.