1. A tobacco seed, a tobacco plant grown therefrom, or a part of said tobacco plant, wherein said tobacco seed, tobacco plant grown therefrom, or part of said tobacco plant comprises a variant polynucleotide comprising a non-natural mutation as compared to a reference sequence, wherein said reference sequence comprises at least 95% sequence identity compared to SEQ ID NO:4, and wherein said non-natural mutation is positioned between two sequences corresponding to SEQ ID NOs: 36 and 37.