There are some MD tags I do not understand. I find no problems understanding most of them, but in some cases the NM (number of mismatches) says there is 1 mismatch and the MD tag is simply "74" (instead of, for example, something like 56A17, 3T71, etc).
How is it possible that there is a mismatch but the MD tag has no information about the mismatch? BTW, I see no mismatch with IGV.
The data was aligned with bwa sampe