Shinya Yamanaka (born September 4, 1962, Ōsaka, Japan) is a Japanese physician and researcher who developed a revolutionary method for generating stem cells from existing cells of the body. This method involved inserting specific genes into the nuclei of adult cells (e.g., connective-tissue cells), a process that resulted in the reversion of cells from an adult state to a pluripotent state. As pluripotent cells, they had regained the capacity to differentiate into any cell type of the body. Thus, the reverted cells became known as induced pluripotent stem (iPS) cells. Yamanaka and British developmental biologist John B. Gurdon shared the 2012 Nobel Prize for Physiology or Medicine for the discovery that mature cells could be reprogrammed.
Yamanaka received an M.D. from Kōbe University in 1987 and a Ph.D. in pharmacology from the Ōsaka City University Graduate School in 1993. That year he joined the Gladstone Institute of Cardiovascular Disease, San Francisco, where he began investigating the c-Myc gene in different strains of knockout mice (mice in which a specific gene has been rendered nonfunctional in order to investigate the gene’s function). In 1996 Yamanaka returned to Ōsaka City University, where he remained until 1999, when he took a position at the Nara Institute of Science and Technology. During this period his research became increasingly focused on stem cells. In 2004 he moved to the Institute for Frontier Medical Sciences at Kyōto University, where he began his landmark studies on finding ways to induce pluripotency in cells. Yamanaka again sought research opportunities in the United States and subsequently was awarded funding that allowed him to split his time between Kyōto and the Gladstone Institute of Cardiovascular Disease. Yamanaka became a senior investigator at the Gladstone Institute in 2007.
In 2006 Yamanaka announced that he had succeeded in generating iPS cells. The cells had the properties of embryonic stem cells but were produced by inserting four specific genes into the nuclei of mouse adult fibroblasts (connective-tissue cells). The following year Yamanaka reported that he had derived iPS cells from human adult fibroblasts—the first successful attempt at generating human versions of these cells. This discovery marked a turning point in stem-cell research, because it offered a way of obtaining human stem cells without the controversial use of human embryos. Yamanaka’s technique to convert adult cells into iPS cells up to that time had employed a retrovirus that contained the c-Myc gene. This gene was believed to play a fundamental role in reprogramming the nuclei of adult cells. However, Yamanaka recognized that the activation of c-Myc during the process of creating iPS cells led to the formation of tumours when the stem cells were later transplanted into mice. He subsequently created iPS cells without c-Myc in order to render the cells noncancerous and thereby overcome a major concern in the therapeutic safety of iPS cells. In 2008 Yamanaka reported another breakthrough—the generation of iPS cells from mouse liver and stomach cells.
Yamanaka received multiple awards for his contributions to stem-cell research, including the Robert Koch Prize (2008), the Shaw Prize in Life Science and Medicine (2008), the Gairdner Foundation International Award (2009), the Albert Lasker Basic Medical Research Award (2009), and the Millennium Technology Prize (2012).