Elimination of zero-repeat subunit in allergenic seed protein 13S globulin using the novel allele in common buckwheat ( Moench).

Common buckwheat ( Moench) seeds contain 13S globulin, the zero-repeat subunit of which is trypsin-resistant and allergenic. Here, its two novel alleles were analyzed for development of hypoallergenic plants. The allele has a Miniature Inverted-repeat Transposable Element (MITE)-like insertion in the 4th exon.

Insertion of ten amino acids into 13S globulin zero-repeat subunit improves trypsin digestibility in common buckwheat ( Moench) seeds.

The 13S globulin zero-repeat subunit is resistant to trypsin and may have higher allergenicity than the 1-6 tandem repeat subunits in common buckwheat ( Moench). To explore alleles useful for lowering allergenicity, amplicon deep sequencing targeting the zero-repeat subunit gene was conducted in bulked genomic DNA from eight cultivars and landraces. The analysis identified a unique allele encoding a zero-repeat subunit with 10 amino acid insertion (10aa) at a position equivalent to the tandem repeat insertion.