Haplotyping barley bmy1 using the SNaPshot assay

Abstract

The allelic status at bmy1, which encodes the enzyme β-amylase 1 in the barley grain, has an important influence over a cultivar’s malting quality. Changes in the malting process have been responsible for the need to improve the thermostability of this enzyme. We have compared a published bmy1 haplotyping assay based on TDI-FRET (template-directed dye-terminator incorporation fluorescence resonance energy transfer) with a SNaPshot protocol by jointly analysing a set of 21 cultivars of known haplotype. The two methods gave the same result, but the SNaPshot assay was easier to interpret. The SNaPshot assay was therefore used to haplotype the Czech malting barley core collection with respect to bmy1. The old Czech cultivar Kasticky was the only entry identified as carrying the high thermostability haplotype, with the remainder carrying either the intermediate or the low thermostability haplotypes. Older materials were the most variable in terms of bmy1 haplotype, but the majority carried the intermediate type. Most of the descendants of cv. Diamant carried the low thermostability haplotype. The most recently released cultivars recommended for the brewing of Czech beer tend to carry the intermediate allele.