Fig. 3.

Genetic evidence for overdominance in Gymnadenia rhellicani. a Polymorphism at Puflatsch; red morph always heterozygous for functional variant (both alternative variants truncate the protein). b Phylogenetic analysis of R2R3-MYB domains (Arabidopsis, AtMYB; Phalaenopsis, PeMYB) places GrMYB1 within ANS regulators (bold branches, posterior probability >80%). c Polymorphism at Bondone; derived variant (deletion/frameshift) is always heterozygous in red and homozygous in white morph. d RNAi of GrMYB1: partial pigment loss and reduced GrMYB1 and GrANS1 expression (red; controls black, 99% confidence intervals) in developing flowers. e Evolutionary relationships and relative frequencies of GrMYB1 alleles (linked SNP positions 612 + 663) across the Alps; non-functional alleles at Puflatsch and Bondone. Map based on ALOS World 3D 30 m digital surface model from Japan Aerospace Exploration Agency, ©JAXA and administrative boundaries from GADM