Homologous sucrose synthase genes in barley (Hordeum vulgare) are located in chromosomes 7H (syn. 1 and 2H Evidence for a gene translocation?

Abstract
The chromosomal location of the two types of sucrose synthase genes, Ss1 and Ss2, has been investigated in barley by Southern blot analysis of wheat‐barley addition lines using non‐cross‐hybridizing‐specific probes corresponding to the C‐terminal regions of their respective CDNA clones (⋍250 bp). The Ss1 gene, whose cDNA of 2,667 bp has been entirely sequenced, is located in the β‐arm of chromosome 7H (syn. 1), while that corresponding to the homologous Ss2 is in the short arm of 2H, suggesting the existence of a translocation event between these two chromosomes in cultivated barley after an initial gene duplication and divergent evolution.