Overview

• The CLCN2 gene, encoding a chloride ion channel, has been confirmed as the key determinant of skin pattern diversity in corn snakes, including Motley and Stripe morphs.
• Motley morphs result from reduced expression of CLCN2, while Stripe morphs arise from a transposon insertion disrupting the gene's function.
• Genetic inactivation experiments reproduced the Stripe phenotype, validating CLCN2's causal role in pattern formation.
• CLCN2 is expressed in chromatophores during embryonic development, where its mutation disrupts pigment cell aggregation, altering blotch patterns into stripes.
• Despite its critical neurological roles in mammals, CLCN2 mutations in corn snakes only affect pigmentation, highlighting species-specific functional divergence.