Researchers have identified 46-kilobase gene cluster encoding five basic helix-loop-helix transcription factors, bHLH1 to bHLH5. One of these transcription factors, specifically the bHLH2, is involved in the amygdalin biosynthetic pathway. Thanks to the findings, it could be possible to prevent the formation of the cyanogenic diglucoside amygdalin, resulting in the sweet kernel trait.
Sánchez-Pérez, R., Pavan, S., Mazzeo, R., Moldovan, C., Cigliano, R. A., Del Cueto, J., … & López-Marqués, R. L. (2019). Mutation of a bHLH transcription factor allowed almond domestication. Science, 364(6445), 1095-1098.