NIPAL4 Deletion Identified in an American Bully with Autosomal Recessive Congenital Ichthyosis and Response to Topical Therapy

The study identified a deletion in the NIPAL4 gene in a 1.5-year-old female American Bully with autosomal recessive congenital ichthyosis, characterized by dry, scaly skin. The dog, homozygous for the NIPAL4 variant, responded positively to topical treatments, including keratolytic and keratomodulator shampoo, emollient spray, and antimicrobial wipes, showing significant improvement within 1 month. This was the first report of the NIPAL4 variant in an American Bully, suggesting a possible founder effect from American Bulldogs. The study recommended further genotyping of American Bullies to estimate the frequency of this deleterious allele and highlighted the potential of genetic testing and topical therapy in managing this condition.