Although the kinked-tailed variant (p.V2A) found in cats is located upstream of the bHLH domains, it represents an amino acid change at an evolutionarily conserved site and may affect the transcriptional regulation effect of HES7, as observed in the cases of the p.D142Y and p.D186Y mutations in human SCD. Here, HES7 is linked to Schnyder corneal dystrophy.