U.S. flag

An official website of the United States government

GTR Home > Conditions/Phenotypes > Cone-rod synaptic disorder, congenital nonprogressive


Congenital nonprogressive cone-rod synaptic disorder (CRSD) is characterized by stable low vision, nystagmus, photophobia, a normal or near-normal fundus appearance, and no night blindness. Electroretinography shows an electronegative waveform response to scotopic bright flash, near-normal to subnormal rod function, and delayed and/or decreased to nonrecordable cone responses (Traboulsi, 2013; Khan, 2014). [from OMIM]

Genes See tests for all associated and related genes

  • Also known as: CRSD, CSNB2B, CABP4
    Summary: calcium binding protein 4

Clinical features


Show allHide all

IMPORTANT NOTE: NIH does not independently verify information submitted to the GTR; it relies on submitters to provide information that is accurate and not misleading. NIH makes no endorsements of tests or laboratories listed in the GTR. GTR is not a substitute for medical advice. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.