Heikkinen, M. E. | Search bioRxiv

bioRxiv2026

Sex-linked dilution colour in the European domestic goose confirmed to be a 1-bp deletion in the Melan-A gene

Plumage colour in domestic geese is an important economic trait and a selection target since the early days of domestication. In European domestic geese of greylag goose (Anser anser) origin, white plumage colour is known to be caused by two independent loci, one causing white spotting and one causing sex-linked dilution, together producing white plumage. Strong candidate mutations have been identified upstream of the EDNRB2/LOC106047519 gene (endothelin receptor B-like) and within the sex-linked MLANA gene (melan-A). To confirm these candidate mutations, we genotyped differently coloured European domestic goose breeds, wild greylag geese, Chinese domestic geese (derived from swan goose A. cygnoid) and European and Chinese domestic geese crossbreeds. One base pair deletion in the MLANA gene (NW_013185876.1: g.950,868 C > -) was confirmed to cause sex-linked dilution, and thus autosexing (almost white gander and goose diluted grey). However, mutation upstream of EDNRB2/LOC106047519 (NW_013185915.1: g. 775,151 G > T) was not the causative mutation for saddleback pattern but strongly linked to it in European domestic geese. We sequenced the EDNRB2 gene and coding sequence of a neighbouring VAMP7 gene (vesicle-associated membrane protein 7) but found no genetic variaion linked to colour. Additionally, we sequenced the coding sequence of TYRP1 (tyrosinase related protein 1), a candidate gene for buff colouration, but no variation linked to colour was found. Further, we genotyped a 14-bp insertion in exon 3 of the EDNRB2 gene, known to be causative of the white phenotype in the Chinese domestic goose, and identified it in one European domestic goose individual.

genetics↗

bioRxiv2019

Long-term reciprocal gene flow in wild and domestic geese reveals complex domestication history

Hybridization has frequently been observed between wild and domestic species and can substantially impact genetic diversity of both counterparts. Geese show some of the highest levels of interspecific hybridization across all bird orders, and two of the goose species in genus Anser have been domesticated providing excellent opportunity for joint study of domestication and hybridization. Until now, knowledge on the details of the goose domestication process has come from archaeological findings and historical writings supplemented with few studies based on mitochondrial DNA. Here, we used genome-wide markers to make the first genome-based inference of the timing of European goose domestication. We also analyzed the impact of hybridization on the genome-wide genetic variation in current populations of the European domestic goose and its wild progenitor: the greylag goose (Anser anser). Our dataset consisted of 58 wild greylags sampled around Eurasia and 75 domestic geese representing 14 breeds genotyped for 33,527 single nucleotide polymorphisms. Demographic reconstruction and clustering analysis suggested that divergence between wild and domestic geese around 5,300 generations ago was followed by long-term genetic exchange, and that greylag populations have 3.2-58.0% admixture proportions with domestic geese, with distinct geographic patterns. Surprisingly, many modern European breeds share considerable (> 10%) ancestry with Chinese domestic geese that is derived from the swan goose Anser cygnoid. We show that domestication process can progress despite continued and pervasive gene flow from the wild form.\n\nSignificance StatementReproductive isolation between conspecific wild and domestic populations is a cornerstone of the domestication process, yet gene flow between such wild and domestic populations has been frequently documented. European domestic geese and their wild progenitor (greylags) co-occur and can hybridize and we show that they represent a particularly persuasive case where wild and domestic populations are not isolated gene pools. Our study makes a first genome-based estimate of goose domestication, which up to now has mostly relied on archaeological findings and historical writings. We show ongoing gene flow between greylags and European domestic geese following domestication, but we also observe a surprisingly large contribution of Chinese domestic geese (a separate species) to the genetic make-up of European domestic geese.

evolutionary biology↗