One month after an operation at Rome's Bambino Gesù Hospital on a 20-month-old child affected by a rare genetic disease, the bone-marrow transplant from his parents using an innovative manipulation of stem cells has been successful and the child is in "good condition", doctors at the Vatican-run pediatric hospital said Thursday.

Alessandro Maria Montresor, known as Alex, will be leaving the hospital in the next few hours after the transplant treatment was concluded "in a positive way". The father's cells, which were manipulated and then infused, "have taken root perfectly", the hospital also said.