The deformed chick wasn't quite right from the start. She didn't run around like baby chicks usually do. To begin with we didn't notice how crooked and bent some of her toes were because of all the fluffy Silkie feathers on legs and toes. We soon noticed that she was missing a fifth toe which SOP for Silkies is 5. The reputable breeder was mortified to have passed her on to us and gave us a new replacement chick. They're reputable private Silkie breeders we bought from them before.
If we gave the deformed chick back to the breeder they would've just culled her but we agreed to keep and nurse her for as long as needed. She gradually ate less and less and her new growth feathers were strange. She was not absorbing nutrients and there was nothing we or our vet could do for malformed internal organs. She was so tiny we didn't want to put her through a bevy of tests. She was content to be a lap baby till she passed. Vet said she probably would've died sooner in a clutch of new hatches on a farm but human care made her life last a little longer.
I have no idea what DNA-sexing does other than tell you if it's a male or female chick. If you are curious look up chicken DNA testing on the internet to see if any of your questions get answered
