Today, it is research with human embryonic stem cells and attempts to prepare cloned stem cells for research and medical therapies that are being disavowed as being ethically unacceptable.

Berg was recognized for "his fundamental studies of the biochemistry of nucleic acids with particular regard to recombinant DNA" while Sanger and Gilbert were honored for "their contributions concerning the determination of base sequences in nucleic acids. He worked with Arthur Kornberg while at Washington University. After developing the technique Berg used it for his studies of viral chromosomes.

Berg received his undergraduate education at Penn State University where he majored in biochemistry. Berg worked as a professor at Washington University School of Medicine and Stanford University School of Medicine in addition to serving as the director of the Beckman Center for Molecular and Genetic Medicine.