What is the correct meaning of cytogenetic notation "inv(4)(p13q22)" ?
- Inversions at chromosome 4, at the p arm 13 is inverted AND at q arm 22 is inverted
- Inversions at chromosome 4, the p13 is Swapped with q22
Those are the break points of the inversion. So chromosome 4 was cut at p13 and q22 and the fragment was reinserted in the reverse direction, giving a pericentric inversion.