Mutants and duplication in chromosome 7 (syn. 5H) in the barley line HA21: duplications may enhance QTLs and serve to make constant linear cis-heterozygosity.
Cytological and linkage data indicate a duplication in the short arm of chromosome 7 (syn. 5H) in the mutant line HA21 (barley, Hordeum vulgare, cv. 'Pirkka'). The associated mutant (ha21) shows a weighted average linkage of 22.1 cM with pld, hitherto an ignored anthocyaninless gene, of cv. Pirkka. Some crosses produce F2 segregants with an exaggerated ha21 phenotype which may represent position effect or increased dosage of the mutant gene through recombination. Compared with cv. Pirkka, HA21 has changes in grain chemistry (alpha- and beta-amylase, beta-glucanase), which may be caused by changed QTL dosage or QTL position effect due to duplication. The use of duplication in creating constant +m/+ m or m+/m+ linear cis-heterozygotes is suggested. Linear cis-heterozygotes may produce stable heterosis or attenuate the undesired effects of drastic mutants.
Ahokas
H
H
Division of Genetics, University of Helsinki, Finland.
Erkkilä
M J
MJ
D002874:Chromosome Mapping; D003433:Crosses, Genetic; D008040:Genetic Linkage; D006579:Heterozygote; D001467:Hordeum / Q000235:genetics*; D005810:Multigene Family; D009154:Mutation; D019655:Quantitative Trait, Heritable; D011995:Recombination, Genetic; D014178:Translocation, Genetic