Natural Variability of Genomic Sequences of Mal d 1 Allergen in Apples as Revealed by Restriction Profiles and Homolog Polymorphism

Apples are a popular fruit worldwide, with many health and nutritional benefits. However, this fruit is also among those that, particularly in Central and Northern Europe, are allergenic due to the Mal d 1 allergen. Mal d 1 is a homologous allergen to Bet v 1—the main pollen allergen of birch. In this study, two different approaches were used to identify the natural length polymorphism of Bet v 1 homologs in apple varieties, with the aim of characterizing their effectiveness. BBAP (Bet v 1 based amplified polymorphism) and RFLP (restriction fragments length polymorphism) profiles were characterized and compared. RFLP analysis recognizes the genetic diversity of M. domestica Mal d 1 sequences at a relatively low level. In BBAP profiles, the genetic dissimilarity was up to 50%, which appears suitable for intraspecific fingerprinting and serves as an additional method for RFLP analysis. RFLP analysis was able to distinguish some varieties that BBAP could not, such as Sonet.