Sequencing of the cDNA revealed two adjacent missense mutations T402C and G403T, resulting in a leucine-to-proline change in amino acid 66 (L66P) in the first doublecortin (DCX) domain of exon 2. Western blot analysis indicates normal quantity and size of the mutant protein, however, immunohistochemistry shows that the protein partially mislocalizes to the transition zone of the shortened axonemes of photoreceptors.