In contrast, hRPE cells of the AMD-protective CFH haplotype (YY402/II62) showed no complement activation following exposure to either Abca4(-/-) or wild-type OS.
Mutations in the ABCA4 gene are responsible for a number of related retinal degenerative diseases, including Stargardt macular degeneration, cone-rod dystrophy, retinitis pigmentosa, and age-related macular degeneration.
Stargardt disease (STGD, also known as fundus flavimaculatus; FFM) is an autosomal recessive retinal disorder characterized by a juvenile-onset macular dystrophy, alterations of the peripheral retina, and subretinal deposition of lipofuscin-like material.
Because A2E accumulation in the RPE is associated with pathogenesis of both Stargardt disease and age-related macular degeneration (AMD) in humans, deletion of Abca4 was introduced into Atg7(flox/flox);VMD2-rtTA-cre+ mice to investigate the role of autophagy during A2E accumulation.
Biochemical defects in retina-specific human ATP binding cassette transporter nucleotide binding domain 1 mutants associated with macular degeneration.
Assuming pseudodominant (recessive) inheritance of allelic defects, linkage analysis positioned the causal gene at 1p21-p13 (lod score 4.22), a genomic segment known to harbor the ABCR gene involved in Stargardt's disease (STGD) and age-related macular degeneration (AMD).
In a subset of inherited retinal degenerations (including cone, cone-rod, and macular dystrophies), cone photoreceptors are more severely affected than rods; ABCA4 mutations are the most common cause of this heterogeneous class of disorders.
Since the retina is highly sensitive to peroxidation and the GPX gene product protects cells from oxidative damage, and the fact that the ABCR gene is considered as a major disease gene in macular degeneration we reasoned that they might serve as candidate genes in a subset of ARMD cases.
Although population studies have indicated that some ABCR variant alleles may enhance susceptibility to AMD, investigation of the extent of ABCR involvement by kindred analysis is complicated by a plethora of environmental and other hereditary factors not investigated in the current study that may also play important roles.