30 questions · 12 almanac · 0 findings

Stem Cells and Reprogramming

Pluripotent cells and techniques for reprogramming cell identity.

Almanac The Genome Does Not Forget
  • What procedure did Ian Wilmut's team use to clone Dolly from a mammary gland cell?
  • Why was Dolly's birth significant for the long-standing biological debate about whether adult cells retain full genetic instructions?
  • How long was Dolly's existence kept secret before it was announced, and why?
Almanac One Lamb, Chosen From 277 Attempts
  • How does somatic cell nuclear transfer actually work to create a clone like Dolly?
  • Why did it take 277 attempts to produce one viable lamb?
  • What long-standing assumption about adult cells did Dolly's birth overturn?
  • What health problems did Dolly develop later in life, and how old was she when she died?
Almanac An Economic Stimulus Built on Human Cloning
  • What did Richard Seed announce he intended to do in 1998, and what qualifications did he actually have to do it?
  • Why did the Ig Nobel committee frame Seed's cloning proposal as an economic stimulus plan?
  • How did Seed's announcement compare technically to what had actually been achieved with Dolly the sheep?
Almanac A Single Cell, Renewing Itself
  • What observation about spleen nodules led McCulloch and Till to the concept of the stem cell?
  • How long did it take for the significance of their discovery to be widely recognized in biology?
Almanac A Skin Cell Persuaded to Forget
  • Which four transcription factors did Yamanaka's team use to reprogram adult skin cells?
  • How do induced pluripotent stem cells differ from embryonic stem cells in their origin?
  • Why did iPSCs sidestep the ethical controversy that had surrounded stem cell research?
  • What medical applications does personalized regenerative medicine using iPSCs promise?
Almanac Skin Cells, Wound Back to the Beginning
  • What are the four Yamanaka factors and what do they do to a skin cell?
  • How did induced pluripotent stem cells change the ethical debate around embryonic stem cell research?
  • Which research groups reported reprogramming human cells to a pluripotent state in 2007?
Almanac A Cell Remembers What It Could Have Been
  • What did John Gurdon's frog nucleus transplant experiment prove about cellular differentiation?
  • How did Shinya Yamanaka reprogram adult mouse cells into a pluripotent state using just four transcription factors?
Almanac The Cell's Past Is Not Its Prison
  • How did Yamanaka reset adult mouse cells to a pluripotent state using only four transcription factors?
  • Why do induced pluripotent stem cells avoid the ethical controversy surrounding embryonic stem cells?
  • What kinds of patient-specific therapies has iPSC technology made possible?
Almanac A Frog Egg Already Knew the Way
  • What did the prevailing biological consensus in the 1960s assume about differentiated cells and their genetic information?
  • How did Gurdon's nuclear transfer experiment with a frog egg and an adult intestinal cell nucleus test that assumption?
  • How did Gurdon's discovery connect to Shinya Yamanaka's later work on induced pluripotent stem cells?