title: RETRACTION - In Vitro Derivation of Human Sperm from Embryonic Stem Cells.
abstract: This article, "In Vitro Derivation of Human Sperm from Embryonic Stem Cells," is being retracted from Stem Cells and Development.    Further details will follow online, and in a subsequent issue of the Journal.
authors: NESCI/Institute of Human Genetics, Newcastle University, United Kingdom;  karim.nayernia@ncl.ac.uk.
authors: Karim
authors: K
authors: Nayernia
authors: Jae Ho
authors: JH
authors: Lee
authors: Majlinda
authors: M
authors: Lako
authors: Lyle
authors: L
authors: Armstrong
authors: Mary
authors: M
authors: Herbert
authors: Manyu
authors: M
authors: Li
authors: Wolfgang
authors: W
authors: Engel
authors: David
authors: D
authors: Elliott
authors: Miodrag
authors: M
authors: Stojkovic
authors: John
authors: J
authors: Parrington
authors: Alison
authors: A
authors: Murdoch
authors: Tom
authors: T
authors: Strachan
authors: Xin
authors: X
authors: Zhang