Why the HDBR is needed
The HDBR will help researchers shed light on a large number of distressing medical disorders. Birth defects taken as a whole are the biggest cause of infant mortality in the Western world. Currently one in 30 babies is born with a significant malformation but the causes of many of these malformations are poorly understood. Studying embryos from the period when most malformations arise will be an important step towards understanding, and perhaps eventually preventing, fetal abnormality.
Clinical benefits
The clinical benefits of research into human embryogenesis are many. For example, it is known that the incidence of spina bifida in babies can be reduced if mothers are given folic acid supplementation in early pregnancy. Studies on early human embryos are beginning to explain this by showing how early developmental processes are related to folic acid metabolism. And in addition to clinical benefits, human embryonic studies will help us understand how a single fertilised egg is transformed into a fully functional human being. This is one of biology's greatest challenges.
Limitations of non-human tissue in developmental biology
Scientists' understanding of the growth and development of many organisms has increased significantly in recent years. Research has identified many of the genes controlling these processes and their functions. A diverse range of species has been studied, with particular focus on the nematode worm, fruit fly, zebrafish, frog and mouse. A striking feature of the studies has been the similarities between the genes controlling development in these species.
There are, however, significant morphological differences between species during early development. If we are to understand human development more fully, it is necessary to study human embryonic material. But up to now, studies in this vital area of research have been limited by the scarcity of the necessary human embryonic tissue.
The recent publication of the first draft of the human genome has opened up new avenues of research. But while the human genome sequence provides an inventory of all human genes, it provides little help with explaining their function. Studies into which genes are turned on and off in human embryos will provide valuable clues to gene function in this key period of human development.