Model for the evolution of the H1 and H2 haplotypes at the Lr10 locus. Genes are indicated by black boxes. The short arrows located below the genes indicate the transcriptional orientation. Identified nested repetitive elements are shown by colored boxes. The evolution of the H1 haplotype is represented on the left side and the evolution of the H2 haplotype on the right side of the figure. The ancestor of the H1 haplotype comprises elements common to both T. monococcum and T. turgidum, and subsequent independent events of insertions/deletions occurred resulting in the modern loci. The H2 ancestor has undergone a deletion comprising Lr10 and the first exon of RGA2. The deletion is indicated by red dashed lines. An inversion indicated by a red arrow and delimited by blue arrows and a dashed rectangle also occurred in the H2 ancestor leading to a disruption of RGA2 that is at the origin of the modern T. aestivum sequence. Green arrows indicate the (TA) repeats possibly involved in the sequence inversion.
