Before revision: The existence of genes along the inactive X which are not silenced explains the defects in humans with abnormal numbers of the X chromosome, such as Turner syndrome (X0 ) or Klinefelter syndrome (XXY).
After revision: , caused by SHOX geneThe existence of genes along the inactive X which are not silenced explains the defects in humans with abnormal numbers of the X chromosome, such as Turner syndrome (X0 ) or Klinefelter syndrome (XXY).