Stem cells and Epigenetics

• Decisions that have to be made about the use of embryonic stem cells

  • source has to be regulated
  • ethical/ moral issues due to it destroying embryos
  • research establishments need to be regulated
  • embryonic stem cells are totipotent so can be used in a wide range of therapies.
• Why can't heart cells differentiate into corneal cells?


  They aren't totipotent, therefore some genes are already activated/ deactivated. They can't differentiate into corneal cells
• Explain how epigenetic changes affect the activation of genes in daughter cells.


  M1- Some genes are activated in stem cells

  M2- due to DNA methylation

  M3- these same genes are activated in the daughter cells
• Why can an individual have greater adult height than their biological parents?


  M1- Height is determined by both environmental and genetic factors.

  M2- Height is an example of polygenic inheritance

  M3- therefore offspring can inherit a mixture of alleles from both parents that increase height.

  M4- an environmental factor can affect height as well