Investigation of Mal d 1 Allelic Variants and Phylogenetic Diversity in Contemporary and Historical Polish Apple Cultivars

Allergy is considered as the most common health problem of XXI century. Apple allergenicity is of great importance and at present the only therapy for food allergy is avoidance. Fruits are important components of a healthy diet, and therefore complete avoidance of apple and related fruits like pear, peach, and cherry can have a significant negative impact since deprives the patient’s diet from important sources of vitamins, minerals and fibers. In order to provide a contribution towards a better understanding of the genetics of the family of Mal d 1 gene, the major apple allergen, and to establish the basis for further research on allelic diversity among cultivars in relation to variation in allergenicity we evaluated Mal d 1 gene variability in contemporary and historical Polish apple cultivars (Malus × domestica Borkh.). We identified new Mal d 1 alleles and further assessed phylogenetic distance between Mal d 1 variants and antigens derived from other food sources. We also predicted possible cross-reactions between allergens originated from Malus x domestica and other plant taxa as well as showed potential binding sites of apple allergens to the antibody. Thanks to multiple sequence alignment of the amino acid sequences limited to residues which serve as interaction partners for the antibody we were able to more precisely establish phylogenetic distance between analyzed antigens in regards to the antigen epitope residues.