The molecular basis of human retinal and vitreoretinal diseases pathologies of other tissues (syndromic forms) or only affects the retina, retinal pigment epithelium and the vireous body (non-syndromic forms). In addition, the mode of inheritance was used as one characteristic feature of the different disease phenotypes in order to categorize them. Our aim was to provide a comprehensive overview about the molecular basis of retinal and vitreoretinal diseases and to discuss selected aspects in more detail.
Non-syndromic retinal and vitreoretinal diseases
Diseases of rod photoreceptor cells (stationary and progressive)Rod photoreceptors represent the vast majority of light sensitive cells in the human retina. There are approximately 20 times more rods than cones. These cells are spezialized for low light intensities and are responsible for visual perception under dim light conditions. The center of the human retina, which contains the macula and fovea centralis, is devoid of rod photoreceptor cells but the flanking areas have the highest rod content, which decreases almost lineary towards the retinal periphery.The two major classes of stationary and progressive retinal diseases in humans arerepresented by different forms of stationary night blindness and retinitis pigmentosa, respectively.
Congenital stationary night blindness / stationary rod diseasesAs the name implies, congenital stationary night blindness (CSNB) is a nonprogressive visual impairment present at birth. However, it is also one of the first symptoms in progressive diseases, including retinitis pigmentosa (RP). Therefore, a differential diagnosis by genetic testing can provide helpful and important information to the affected individuals and families, in order to exclude or confirm the clinical diagnosis and to provide counselling. Bech-Hansen et al., 1998; Bech-Hansen et al., 2000;Dryja et al., 1993; Dryja et al., 1996; Dryja et al., 2005; Fuchs et al., 1995;Gal et al., 1994;Li et al., 2009; Pusch et al., 2000;Strom et al., 1998;Wycisk et al., 2006;Yamamoto et al., 1997;Zeitz et al., 2005;Zeitz et al., 2006 inheritance. The disease was found to be due to mutations in the alpha subunit of transducin (Dryja et al., 1996). The Schubert Bornschein disease can be subdivided in (i) CSNB1 or complete CSNB and (ii) CSNB2 or incomplete CSNB. In CSNB1, the rod b-wave is significantly reduced or absent, while that of the cones is largely
Retinitis pigmentosa and progressive rod cone diseasesThe term retinitis pigmentosa (RP) describes a group of clinically similar phenotypes associated with genetically heterogeneous causes. The disease onset and progression may vary significantly among patients, even within the same family. The patients frequently experience night blindness in the early phase of the disease, The molecular basis of human retinal and vitreoretinal diseases Collin et al., 2008; den Hollander et al., 1999; Dryja et al., 1995; Gal et al., 2000; Huang et al., 1995; Martinez-Mir et al., 1998;Maw et al., 1997;Maw et al., 2000;McLaughlin et a...
