Heteroalleles in Common Wheat: Multiple Differences between Allelic Variants of the Gli-B1 Locus

Abstract

The Gli‐B1‐encoded γ‐gliadins and non‐coding γ‐gliadin DNA sequences for 15 different alleles of common wheat have been compared using seven tests: electrophoretic mobility (EM) and molecular weight (MW) of the encoded major γ‐gliadin, restriction fragment length polymorphism patterns (RFLPs) (three different markers), Gli‐B1‐γ‐gliadin‐pseudogene known SNP markers (Sin-gle nucleotide polymorphisms) and sequencing the pseudogene GAG56B. It was discovered that encoded γ‐gliadins, with contrasting EM, had similar MWs. However, seven allelic variants (desig-nated from I to VII) differed among them in the other six tests: I (alleles Gli‐B1i, k, m, o), II (Gli‐B1n, q, s), III (Gli‐B1b), IV (Gli‐B1e, f, g), V (Gli‐B1h), VI (Gli‐B1d) and VII (Gli‐B1a). Allele Gli‐B1c (variant VIII) was identical to the alleles from group IV in four of the tests. Some tests might show a fine difference between alleles belonging to the same variant. Our results attest in favor of the independent origin of at least seven variants at the Gli‐B1 locus that might originate from deeply diverged genotypes of the donor(s) of the B genome in hexaploid wheat and therefore might be called “het-eroallelic”. The donor’s particularities at the Gli‐B1 locus might be conserved since that time and decisively contribute to the current high genetic diversity of common wheat.