Background: Panda ( s) is an autosomal recessive mutation, which displays overall white plumage color with spots of wild-type plumage in the Japanese quail ( Coturnix japonica). In a previous study, the s locus was included in the same linkage group as serum albumin ( Alb) and vitamin-D binding protein ( GC) which are mapped on chicken ( Gallus gallus) chromosome 4 ( GGA4). In this study, we mapped the s locus on the microsatellite linkage map of the Japanese quail by linkage analysis.
Results: Segregation data on the s locus were obtained from three-generation families ( n = 106). Two microsatellite markers derived from the Japanese quail chromosome 4 ( CJA04) and three microsatellite markers derived from GGA4 were genotyped in the three-generation families. We mapped the s locus between GUJ0026 and ABR0544 on CJA04. By comparative mapping with chicken, this locus was mapped between 10.0 Mb and 14.5 Mb region on GGA4. In this region, the endothelin receptor B subtype 2 gene ( EDNRB2), an avian-specific paralog of the mammalian endothelin receptor B gene ( EDNRB), is located. Because EDNRB is responsible for aganglionic megacolon and spot coat color in mouse, rat and equine, EDNRB2 is suggested to be a candidate gene for the s locus.
Conclusion: The s locus and the five microsatellite markers were mapped on CJA04 of the Japanese quail. EDNRB2 was suggested to be a candidate gene for the s locus.