These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Long-term follow-up of the human phenotype in three siblings with cone dystrophy associated with a homozygous p.G461R mutation of KCNV2. Author: Friedburg C, Wissinger B, Schambeck M, Bonin M, Kohl S, Lorenz B. Journal: Invest Ophthalmol Vis Sci; 2011 Nov 07; 52(12):8621-9. PubMed ID: 21911584. Abstract: PURPOSE: To provide an up to 14-year overview of the early ocular phenotype in siblings with a homozygous p.G461R mutation in the KCNV2 gene. METHODS: Two brothers and their sister were followed-up clinically from ages 5 years, 4 years, and 2 months, respectively, including complete ophthalmological examinations. Goldmann visual fields, two-color-threshold (2CT) perimetry, color vision testing, optical coherence tomography (OCT), fundus autofluorescence (FAF), and Ganzfeld electroretinograms (ERGs) were performed according to age-related capabilities. Genetic analyses included whole genome linkage analysis, homozygosity mapping, and candidate gene sequencing. RESULTS: All three siblings were homozygous for the p.G461R mutation. At 5 months, the younger brother had no nystagmus and Teller-acuity of 3.2 cyc/deg. At older age, all three presented nystagmus, increased light sensitivity, reduced color discrimination, and relative central scotomas. Visual acuities ranged from 20/200 to 20/70. The macula developed minor irregularities of the RPE, thinning in optical coherence tomography, and a ring of increased FAF. Scotopic (rod) sensitivity was reduced by 2 log and photopic sensitivity by 1 log in two-color-threshold perimetry. ERG responses were markedly delayed. Photopic amplitudes were severely reduced. Scotopic b-waves rose steeply with flash intensity, but for the standard flash supernormal amplitudes were only reached in the girl. CONCLUSIONS: FAF was similar to that in cone-rod dystrophy. Although cone dysfunction was accompanied by rod dysfunction, and scotopic ERGs in patient 2 deteriorated, no patient demonstrated any unequivocal sign of rod degeneration. Grossly delayed b-waves with a steep response-versus-intensity relationship rather than supernormal amplitudes should remind clinicians of this specific condition.[Abstract] [Full Text] [Related] [New Search]