Description:
Partial featherlessness is a mutation that causes coturnix quail to have patches of bare skin across the back of their head, back down, stomach, thighs, and chin. It has been confirmed in a lab, though it is still under-researched and needs more information.
It is a partially lethal mutation, with high mortality in chicks from hatch to maturity. It is possible for birds to survive to adulthood and reproduce, though fairly rare. Chicks will have no buds for feathers in the areas mentioned, and they do not grow the feathers in as they mature.
It is believed to be linked to the black-at-hatch gene, as there is a high rate of incidence between the black-at-hatch chicks and the partial featherlessness. They are not on the same locus, but likely on the same chromosome and very close to the same locus. Therefore, it is likely to be seen almost entirely on black-at-hatch chicks and not elsewhere.
It is not believed to be in public hands at this time, and no further information after 2008 is available.
Breeding with Partial Featherless
Partial Featherless x Partial Featherless = high mortality, 100% Partial Featherless
Partial Featherless x Normal Black-At-Hatch = 100% het. Partial Featherless, appears partial featherless (HPF)
Partial Featherless x Normal = 100% Gene Carriers
Partial Featherless x HPF = 50% Partial Featherless, 50% HPF
HPF x HPF = 25% Partial Featherless, 50% HPF, 25% normal Black at Hatch
Partial Featherless x Gene Carriers = Lower rate of partial featherless, higher rate of normal chicks. Percentages unknown
HPF x Normal = Normal chicks, some gene carriers
HPF x Black-at-Hatch = 50% HPF, 50% Black-at-Hatch
References & Further Reading
Tsudzuki, Masaoki. "Mutations of Japanese quail (Coturnix japonica) and recent advances of molecular genetics for this species." The journal of poultry science 45.3 (2008): 159-179.