White Spots on Ball Pythons – What You Need to Know

tfec phenotypes in reptiles and other vertebrates

Identifying genes that affect color across a wide range of vertebrate species can lead to a deeper understanding of the mechanisms that underlie variation in color and pattern. Given the absence of iridophore and xanthophore cell types in mammals, it is particularly important to expand functional genetic studies of pigmentation beyond mice to better understand the biology of these chromatophore cell types. For example, while we found that tfec affects reptile color, a mouse study showed that tfec mutants have normal coat pigmentation,56 highlighting the need to study a wider range of taxa than traditional model organisms. Indeed, tfec was not included in a recent curated list of genes known to affect pigmentation.16 However, more recent work on zebrafish has shown that tfec is required for iridophore cell fate specification.36 Zebrafish tfec mutants also display delayed development of melanophores and xanthophores, but these chromatophores recover by day 4 post-fertilization. The tfec-associated phenotypes in reptiles and zebrafish contrast with reported mitf phenotypes in these species. In zebrafish, mutations to mitf result in a loss of melanophores, a reduction in xanthophores, and an increase in iridophore density.57 In contrast, Texas rat snakes with a mutated mitf gene are leucistic (i.e., all white), lacking melanophores and xanthophores but showing no difference in iridophore density relative to the wild type.33 Therefore, mutations in tfec and mitf produce distinct pigmentation phenotypes, with mitf playing a key role in melanophore development across vertebrates and tfec in iridophore development in fish and lizard models.

Our results support the conclusion that mutations to tfec in ball pythons cause piebaldism or white spotting, whereas in the brown anole they result in hypopigmentation and lack of iridophores. However, three main points remain unresolved. First is the question of what accounts for the species-specific differences in pigmentation phenotypes. It is known that ball pythons and lizards likely acquire their adult color pattern by different mechanisms.5 Ball pythons have a fixed pattern specified in the embryo, prior to hatching and scale development, and as adults they do not show scale-by-scale coloration. In contrast, many lizards exhibit scale-by-scale coloration that is specified between the juvenile and adult stage. Thus, differences in the timing of gene expression of chromatophores may play a role in the species-specific differences in pigmentation phenotypes. Also unresolved is whether piebald ball pythons have iridophores in either pigmented or white skin. In the Texas rat snake, white coloration arises with iridophores present.33 In the leopard gecko, skin from the ventral side is white but features a complete absence of all chromatophores.58 Since tfec is required for iridophore development in both the brown anole and zebrafish, the white patches in piebald ball pythons may lack all chromatophores. However, TEM imaging will be needed to confirm the chromatophore content of piebald skin in ball pythons. A third point that requires further study is the role of the splice site deletion we detected in snakes and the function of different TFEC protein isoforms across reptile taxa. The splice site deletion itself does not cause piebaldism, since it is present in wild-type ball pythons and other snake species. However, two distinct splice acceptor sites are conserved across many squamate reptiles, and our data demonstrate that both acceptor sites are used in anoles. Whether the ability to produce different TFEC isoforms contributes to species-specific differences in tfec function remains to be tested.

In summary, the finding of a nonsense mutation associated with the piebald phenotype in ball pythons in combination with targeted mutation and TEM imaging in a brown anole model shows tfec has an important role in reptile coloration. Mutations to tfec lead to hypopigmentation and a loss of iridophores in the skin and eyes of brown anoles. In snakes, tfec is likely to be required for the development of chromatophores migrating to body regions that correspond to leucodermic patches observed in piebald ball pythons. Our work highlights the advantages of using ball pythons as a model organism and working with non-academic communities like reptile breeders to accelerate discoveries in pigmentation research in an under-studied class of vertebrates.

Further information should be directed to lead contact Alan Garcia-Elfring ([email protected]).

This study did not generate new unique reagents.

Raw sequence data are available at SRA: PRJNA924959

Figure A small sample of the phenotypic variation found in captive-bred ball pythons (Python regius).

(A) Wild type, (B) piebald, (C) banana piebald, (D) pastel piebald, (E) pastel HRA enhancer, (F) ultramel clown, and (G) banana champagne. Photo credit: pethelpful.com (A) and Designing Morphs (B–G).

We investigated the genetic basis for a classic color morph found in the pet trade and common across a wide range of vertebrate taxa, the piebald. This phenotype is characterized by leucodermic patches and has been described by commercial breeders as recessive.34 Here, we analyze publicly available clutch data to investigate the mode of inheritance of the piebald phenotype in ball pythons and use whole-genome sequencing and population genomics to identify the genomic region likely containing the causal mutation. Through the annotation of genetic variants (SNPs and indels), we identified a candidate causal mutation in a gene coding for a transcription factor. We functionally validated this locus in a squamate model using CRISPR/Cas9 gene editing and confirmed an effect on chromatophore development by transmission electron microscopy (TEM) imaging.

SNAKE MITES? – REMOVE THEM, FOREVER!

FAQ

What are the white patches on my snake?

It’s still likely related to shedding or possibly a skin issue like a fungal infection. If the white patches look raised, crusty, or seem unusual beyond a normal shed, it might be something more serious.

How to tell if a ball python has mites?

• Appearance:

  Mites appear as small, black or red, moving dots, sometimes described as “pinpoint” size. 

• Location:

  They often congregate around the eyes, nostrils, and the gular fold (the crease of skin on the snake’s chin). 

• Mite Feces:

  You might see white flakes or specks, which are the mite feces, particularly on dark-colored snakes. 

• Behavior:

  An infected snake may soak in its water bowl excessively, trying to drown the mites. 

• Other Signs:

  You might also notice mites on your hands after handling the snake, or see them moving on the enclosure walls. 

• Raised Scales:

  Mites can cause raised scales, and you might be able to see them under a slightly raised scale. 

• Lethargy and Loss of Appetite:

  Infected snakes may become lethargic and lose their appetite. 

• Excessive Rubbing:

  You might notice your snake rubbing against objects in the enclosure. 

What does scale rot look like on a ball python?

• Early Signs:

  • Discoloration: Look for abnormally dark or discolored scales, especially on the belly, tail, or areas that come into contact with substrate or waste. 

  • Raised or Swollen Scales: Scales may appear lifted or swollen, indicating inflammation or infection beneath the surface. 

  • Blisters: Small, fluid-filled blisters may appear, initially clear, but can become infected and develop into pustules with yellow or blood-tinged material. 

• Progression:

  • Crusty or Damaged Surfaces: As the infection progresses, scales may become crusty, damaged, or even fall off. 

  • Foul Odor: A foul odor can be a sign of a bacterial infection. 

• Other Signs:

  • Decreased Appetite: A snake with scale rot may lose interest in food. 

  • Movement Alterations: The snake may become lethargic or have difficulty moving. 

  • Increased Aggression: Some snakes may become more aggressive due to pain or discomfort. 

• Causes:

  • Poor Husbandry: Unsanitary living conditions, improper humidity, temperature imbalances, and poor air circulation can contribute to scale rot. 

  • Moisture: Excessive moisture in the enclosure can create an environment where bacteria and fungi thrive. 

  • Nutritional Deficiencies: A poor diet can weaken the snake’s immune system, making it more susceptible to infection. 

  • Physical Damage: Injuries or abrasions can create entry points for bacteria. 

• Treatment:

  • Veterinary Care: It’s crucial to seek veterinary care for scale rot, as it can be a serious and potentially life-threatening condition. 

  • Hygiene: Ensure the enclosure is clean and dry. 

  • Soaks: Soaking the snake in a diluted solution of povidone-iodine (like Betadine) can help to disinfect the affected areas. 

  • Topical Antibiotics: Applying a triple antibiotic ointment to the affected areas can help to prevent further infection. 

  • Quarantine: Isolate the affected snake to prevent the spread of infection. 

What does a ball python respiratory infection look like?

Snakes with respiratory infections may have excess mucus in their mouths, nasal discharge, lethargy, loss of appetite, wheezing, and may make “gurgling” sounds or breathe with an open mouth.

What causes dermatitis in ball pythons?

Dermatitis in ball pythons is a secondary ball python skin infection that typically results in skin lesions. It is caused by bacteria that takes hold as a result of parasites (mites/ticks), viruses, fungi, skin tumors, improper or stuck shedding, thermal burns, excessive moisture in the substrate, high humidity, or filthy cages.

How do you know if a ball python has mites?

You might see mites as red or black moving spots around the snake’s mouth, eyes, grooves of its lower jaw, and in the folds of its skin. You can also tell if your ball python has mites through the presence of white flecks (mite feces) all around the enclosure and on the snake’s body. Thoroughly bathe the snake in warm water.

Do ball pythons have skin problems?

It is important to be aware of the various ball python skin problems that can affect your pet and to take proactive measures to prevent and treat these issues. Dermatitis, scale rot, dysecdysis, thermal burns, mites, ticks, and skin wounds or trauma are all potential concerns that can impact the health and well-being of ball pythons.

Can ball pythons get blisters?

If left untreated, your ball python could develop skin lesions or pus-filled blisters. Bathe your pet in betadine solution. Spray affected areas on the skin with antimicrobial sprays several times a day. If your snake has pus-filled skin lesions and blisters, please take your ball python to the vet for the right treatment.

Can ball pythons shed their skin in one piece?

Healthy snakes can shed their skin in one piece. However, in some snakes, the shedding process can get stuck or difficult. Improper or stuck shed in ball pythons is known as dysecdysis. The shed skin comes off in several pieces instead of in a single piece. It may get stuck around the snake’s head or eyes.

Why do ball pythons get sores?

It is very common for ball pythons to develop sores on their skin as a result of their habitat. They can get burns from their heat lamps. They can scratch themselves on rough surfaces. They can develop blisters from slithering over the same textures repeatedly.