Below is an instruction from Human. Write a response.
    ### Instruction:
    How to diagnose X-linked congenital stationary night blindness ?
    ### Response:
    Is genetic testing available for X-linked congenital stationary night blindness? Yes. About 45% of individuals with XLCSNB have the complete form, which is caused by mutations in the NYX gene. The other 55% have the incomplete form, which is caused by mutations in the CACNA1F gene.
    