What information gives me MRNM field in SAM file? [NGS]

Question

[margarett]

If the MRNM field is = it means that is the same as RNAME but what if I have a number there? What kind of information this does field give to me?

[GenoMax]

MRNM is not defined in SAM specification. Where are you seeing this?

[margarett]

The field is called in two ways: MRNM/RNEXT. In the documentation is only RNEXT.