The Striped mutation results in the boa’s saddles fusing to form a stripe which can run from the head into the tail, however the degree of striping is highly variable. Their tail is a bold red which is caused by an increase in the quantity of erythrophores. Erythrophores synthesize the enzymes which convert carotenoids into the red pigment erythrina.
This mutation is autosomal recessive and originates from South American boas. In order to express this mutation, a boa must have two homologous alleles of the mutated gene. If a boa only has one mutated allele and one normal allele then the animal is heterozygous and the phenotype will similar that of a wild boa. However, boas which are heterozygous for this trait have very intense red tails.