. "The process involved in retention of mRNAs that have incorrectly formed 3'-ends within the nucleus at the site of transcription." . . . "nuclear retention of pre-mRNA with aberrant 3'-ends at the site of transcription" . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .