Original sentence: CD34-positive and CD38-negative).Recently, it has been discovered that the blood within the umbilical cord, known as cord blood, is a rich and readily available source of primitive, undifferentiated stem cells (i.Some parents have chosen to have this blood diverted from the baby's umbilical blood transfer through early cord clamping and cutting, to freeze for long-term (and costly) storage at a cord blood bank should the child ever require the cord blood stem cells (for example, to replace bone marrow destroyed when treating leukemia).These cord blood cells can be used for bone marrow transplant.This practice is somewhat controversial,  with critics asserting that early cord blood withdrawal actually increases the likelihood of childhood disease
Edited sentence: The practice of cord blood harvesting for private banking is controversial, with critics asserting that early cord blood withdrawal actually increases the likelihood of childhood disease