ONLINE MUTATION REPORT Achromatopsia caused by novel mutations in both CNGA3

omplete achromatopsia or rod monochromatism is a stationary cone dystrophy, with an incidence of,1 in 30 000, in which functional cones are absent from the retina.1 2 Affected individuals usually present in infancy with nystagmus, poor visual acuity (6/60–6/36), photophobia, and complete colour blindness. Fundal examination is normal, but electroretinography reveals absent photopic (cone) responses and normal scotopic (rod) responses. Individuals with incomplete achromatopsia retain some colour vision.3 Achromatopsia is recessively inherited and genetically heterogeneous. To date, three achromatopsia genes have been characterised, the first two described being CNGA34–6 and CNGB3,7–9 located at chromosome positions 2q11 and 8q21 respectively. CNGA3 and CNGB3 respectively code fo