In other species: elegant crested-tinamou , chicken , Australian magpie , eastern bluebird , spotted nothura

Categories: Pigmentation phene

Mendelian trait/disorder: unknown

Disease-related: no

Species-specific description: see also OMIA:002589-8839 : Eggshell colour, ABCG2-related in Anas platyrhynchos

Mapping: Liu et al. (2021) used genome-wide association analysis and identity by descent to finely map green egg colour to a 179-kb region of Chr4 based on the resequencing of 352 ducks (Anas platyrhynchos) from a segregating population resulting from the mating of Pekin ducks (white-shelled eggs) and mallards (green-shelled eggs). We further narrowed the candidate region to a 30-kb interval ... . Among the genes located in the finely mapped region, only one transcript of the ABCG2 gene (XM_013093252.2) exhibited higher uterine expression in green-shelled individuals than in white-shelled individuals, as supported by transcriptome data from four populations. ABCG2 has been reported to encode a protein that functions as a membrane transporter for biliverdin. Sanger sequencing of the whole 30-kb candidate region (Chr4: 47.41-47.44 Mb) and a plasmid reporter assay helped to identify a single nucleotide polymorphism (Chr4: 47,418,074 G>A) located in a conserved predicted promoter region whose variation may alter ABCG2 transcription activity."