Phantom Alicorn Development Syndrome, or PADS is a rare genetic disorder that affects only alicorns. It is characterized by a fluffy that would normally be born an alicorn instead not developing the characteristic horn and wings, often appearing as a standard earthy instead. They will almost always develop faster than their littermates, opening their eyes and talking several days before them. They will also usually be smarter than other fluffies, more in line with alicorns if not a little smarter in some cases.
The disorder is caused by duplication of a number of genes that are thought to code for alicorn phenotypes; the alicorn traits are actually caused by several clusters of genes rather than just a singular “alicorn gene” or the handful of genes that code for pegasi and unicorns. The misreading of genetics in the developing foal can lead to just a horn or just wings developing in what otherwise would have been an alicorn, although this is rare. What is far more common, but still a low chance outcome, is for the horn and wings to develop malformed, sometimes to the point of needing to be removed for the health of the fluffy, or not develop at all.
In general, it is all but impossible to pick out a foal suffering from PADS without a genetic screening or waiting to observe the rapid development and/or heightened intelligence. It is relatively common for some PADS foals to be born with lumps or other skin blemishes where horns and wings would normally be in an alicorn. This is usually more reliably observable in adults rather than foals so it is really more useful in diagnosing PADS in adults that weren’t observed as foals in order to distinguish a fluffy with PADS from a just above average intelligent fluffy.
When PADS occurs in the wild, the affected fluffies have a high rate of survival due to their increased intelligence and will often become the herd smarty. It should be noted that they will almost always become “smarty friends” rather than the common smarty as they posses actual practical and emotional intelligence that allows then to lead herds effectively rather than the “all bluster, no substance” approach of your average smarty. On another note, these fluffies might still have the alicorn fear as they often don’t have alicorn presenting parents or siblings and thus don’t become accustomed to them. They do tend to adapted quickly though do their intelligence.
PADS fluffies are actually rather popular with breeders as their genetic disorder does not seam to affect their ability to actually produce healthy alicorns with the added bonus of not having to find an alicorn tolerant partner for it to mate with as it just presents as regular earthy.