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Published on: September 25, 2013
A cis-regulatory mutation of PDSS2 causes silky-feather in chickens
Chungang Feng1, Yu Gao2, Ben Dorshorst3
1State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing, China; National Engineering Laboratory for Animal Breeding, China Agricultural University, Beijing, China; College of Animal Science and Technology, China Agricultural University, Beijing, China.
Abstract:
Silky-feather has been selected and fixed in some breeds due to its unique appearance. This phenotype is caused by a single recessive gene (hookless, h). Here we map the silky-feather locus to chromosome 3 by linkage analysis and subsequently fine-map it to an 18.9 kb interval using the identical by descent (IBD) method. Further analysis reveals that a C to G transversion located upstream of the prenyl (decaprenyl) diphosphate synthase, subunit 2 (PDSS2) gene is causing silky-feather. All silky-feather birds are homozygous for the G allele. The silky-feather mutation significantly decreases the expression of PDSS2 during feather development in vivo. Consistent with the regulatory effect, the C to G transversion is shown to remarkably reduce PDSS2 promoter activity in vitro. We report a new example of feather structure variation associated with a spontaneous mutation and provide new insight into the PDSS2 function.
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