Our group studies disease mechanisms in inherited retinal degenerations (IRDs), and evaluates efficacy and safety of potential treatments. IRDs result in vision loss due to mutations in more than 200 different genes and include diagnoses such as Retinitis Pigmentosa, Stargardt Disease, Leber Congenital Amarousis, and others. There are multitudes of different pathological mechanisms resulting from different mutations. Our group uses non-invasive tests to link changes in retinal structure and function to underlying molecular pathology. We also develop and evaluate novel outcome measures for use in clinical trials.
Feb 8, 2016: Paper published in Ophthalmic Genetics
SPATA7 mutations have been associated with different autosomal recessive retinal degeneration phenotypes. Long-term follow-up has not been described in detail. A Hispanic patient with SPATA7 mutations was evaluated serially over a 12-year period with kinetic and static chromatic perimetry, optical coherence tomography (OCT), and fundus autofluorescence (AF) imaging. Electroretinography (ERG) was performed at the initial visit. The patient was homozygous for a mutation in SPATA7 (p.V458fs). At age 9, the ERG showed an abnormally reduced but preserved rod b-wave and no detectable cone signals. There were two islands of vision: a midperipheral island with greater cone than rod dysfunction and a central island with normal cone but no rod function. Serial measures of rod and cone vision and co-localized retinal structure showed that the midperipheral island slowly became undetectable. By age 21, only the central island and its cone function remained, but it had become more abnormal in structure and function. The disease resulting from SPATA7 mutations in this patient initially presented as a cone-rod dystrophy (CRD), but changed over time into a phenotype more reminiscent of late-stage retinitis pigmentosa (RP). The differential diagnosis for both CRD and RP should include this rare molecular cause of autosomal retinal degeneration. An evolving phenotype complicates not only clinical diagnosis and patient counselling but also future strategies aimed at treating specific retinal regions.
Matsui R, McGuigan III DB, Gruzensky ML, Aleman TS, Schwartz SB, Sumaroka A, Koenekoop RK, Cideciyan AV, Jacobson SG. SPATA7: Evolving phenotype from cone-rod dystrophy to retinitis pigmentosa. Ophthalmic Genetics 2016. [PubMed]