Description:
The silkie gene in chickens causes the feathers to be a silky, wooly-type texture similar to chick down. The "look" is created from the feathers having long barbs and lacking the "scroll" portion of the feather that keeps the barbs together (1).
There are no health issues with the silkie gene, although birds with silkied feathers often are less cold tolerant and more prone to hypothermia because they can't regulate body temperature through their feathers as well (2).
It is only recognized by the APA for the Silkie chicken breed, though the mutation can also be found in Seramas and Cochins, and can be introduced to any breed (3).
Because the silkie gene is recessive, it will cannot be seen from outcrossing. You cannot see the carrier gene at all, so birds carrying only one copy of silkie and non-silkied birds appear the same.
Silkied x silkied = 100% silkied offspring
Silkied x nonsilkied = 100% silkie carriers
Silkied x Silkie Carrier = 50% Silkied, 50% silkie carriers
Silkied Carrier x Silkied Carrier = 25% nonsilkied, 50% silkied carrier, 25% silkied
Silkied carrier x nonsilkied = 50% silkied carrier, 50% nonsilkied.
References & Further Reading
Somes, Ralph G. Jr., "International Registry of Poultry Genetic Stocks" (1988). Storrs Agricultural Experiment Station. 29. https://opencommons.uconn.edu/saes/29
Feng C, Gao Y, Dorshorst B, Song C, Gu X, Li Q, et al. (2014) A cis-Regulatory Mutation of PDSS2 Causes Silky-Feather in Chickens. PLoS Genet 10(8): e1004576. https://doi.org/10.1371/journal.pgen.1004576
American Poultry Association. (2023). American Standard of Perfection (45th ed.).