Type: Incomplete Dominant
First Produced By: Jan Eric Engell
Issues: Wobble, Lethal Super
First Produced In: 1997
Last Updated: 2022-06-30
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This gene reduces patterning and reduces the darker pigments. Many snakes with this gene also display more intense yellow pigment. 
It is an incomplete dominant gene with the super form being Leucistic. Sadly, the homozygous form is lethal. There have been some cases where the leucistic has survived for a brief time outside the egg, but they always end up perishing within a day. It has been shown that the issue is with the development of the lungs. 
There are neurological issues that are associated with this gene. This stems from a failure of certain cell types to migrate to the brain from the neural crest during embryonic development.
All jags have this issue. The symptoms can be as mild as poor coordination or as severe as corkscrewing. The issues seem to present themselves when the snake becomes stressed. There are some jags that don’t show any signs and others that come out of the egg having issues. This condition doesn’t seem to affect the snakes’ overall health since they eat, shed and breed without any issues. This is the same condition that you see in spider ball. 
No snake with the super form of the Jaguar gene has survived longer than a day.
This is normally caused by defects in the lungs. Snakes with only one copy also have neurological issues. This can be as minor as a slight wobble that is nearly unnoticeable to animals that corkscrew and cannot right themselves easily.
It seems the defect is related directly to the gene, so it cannot be bred out. This makes this nearly identical to the spider gene in ball pythons, including the lethal super form. 
The Jaguar morph was originally found in a coastal carpet python (M. s. mcdowelli) in 1994. The morph was named in 1997. 
This morph originated from Jan Eric Engell.
In 1994, after several years of breeding coastal carpet pythons, he produced an unusual looking carpet python.
In 1997 he named the morph the Jaguar and set out to see if it was recessive or incomplete dominant.
In 1998 he bred the jag to an unrelated female coastal carpet. Unfortunately, the clutch only resulted in 4 good eggs. However, one of the babies did turn out to be a jag.
Jan used the same pair in 1999 and produced 12 babies. Four were normal and eight were jags. All of these snakes went to the U.S. and they were big $$ back then. 
The head of the Jaguar displays the usual splattered headstamp of a Normal Carpet Python.
This is one of the first genetic mutations that popped up in carpet pythons. This morph usually has a reduction in overall pattern and reduces the dark pigment and seems to increase the yellow pigment as well. [^4]
The body of the Jaguar Carpet Python has a reduced pattern where dark pigmentation is stripped away.
The tail follows the same coloration as the rest of the body.
While it is perfectly legal to breed the Jaguars, organizations like the IHS in Europe have banned the sale of any Carpet Python carrying the Jaguar gene at their events. 
No known proven lines
No known related traits