Allelic: One member of a pair or series of genes that occupy a specific position on a specific chromosome.
A decade ago, I fell head over heels for a purple albino reticulated python. Yellow brighter than a kindergartener’s crayola happy-face sun, orange of such brilliance it sends the most advanced DSLR cameras into complete fits…and the purple…oh the PURPLE! It was as if Salvador Dali had melted fields of French lavender and Dutch tulips into graceful serpentine form.
The price to own one was steep enough to keep them on my wish list, where they have remained, unspoken-but not forgotten-ever since.
This past February, Jason happened to be stateside and decided to take some of our ball pythons up to Arlington to vend at the big NARBC show. He took the opportunity to donate an animal for the USARK fundraiser auction on Saturday evening. As fate would have it, Bob Clark also donated an animal- a lavender albino motley retic - which would end up coming home with Jason.
Though not as striking to me as a purple albino, the lavender is incredibly lovely. Cameras seem to have trouble capturing the purple/lavender hues with all snakes- you really must see one in person to truly appreciate it. The story of the albino retic is rather interesting, and has a lesson to teach for those interested in genetic inheritance and multiple alleles.
In 1994, Bob Clark imported the first albino (amelanistic) reticulated python, which was a lavender. After several years and crossing resulting offspring together, it was found that the original strain had three phenotypical presentations: white, lavender and purple. In essence, the original import had two albino alleles to offer to its offspring- one purple and one white. When a retic inherits two white alleles, it looks white. One white allele, one purple allele, and you get a lavender. Two purple alleles- and you get a purple. Sounds so simple, right?
So how does this knowledge apply to ball python breeders, you might ask? Ever hear of a Toffino? Or Candino, perhaps? Since Candy and Toffee are genetically compatible and are simply two bloodlines of the same mutation, I’ll use Candy from here forward for brevity’s sake.
When you cross a Candy to a classic Albino, all the babies will be Candinos. This unexpected genetic compatibility really threw a lot of people for a loop, and many fail to realize its significance even now. A Candino is a parallel to that original imported Clark strain albino reticulated python. The Candino has one purple (Candy) and one white (Albino) allele. When breeding two Candinos together, each parent has an allele of each type to offer up. If the offspring inherits two Albino alleles, it will be a classic white Albino. If it inherits one Albino and one Candy allele, it will be lavender (Candino) and if it inherits two Candy alleles, it will be a pure Candy (purple).
It’s also important to note that Blonde retics and type 2 albino retics are NOT compatible with the Original strain white/purples. Likewise, the Albino/Candy albinos are not compatible with the “Lavender Albino” mutation in ball pythons.
Other recessive allelic mutations encountered in captive herpetoculture include the Paradigm boa and the Ultramel cornsnake. In both cases, a form of albino sits at the same locus as a form of hypomelanism. Boawoman hypo and Sharp albino “line up” to produce a Paradigm boa. Neither Kahl strain albino nor VPI caramel albino can be substituted to create the same result. In the cornsnake, Ultra hypo “lines up” with amelanism to produce the Ultramel corn.
Until snake genomes are mapped, we are left to make deductions based on observations of captive breeding trials. To me, this is part of the fun of breeding reptiles, however mystifying the puzzles become, and no matter how long it takes to work them out. With jewels such as the purple albino retic as the reward for unraveling the mysteries, it’s well worth the effort!