Age-related macular degeneration(AMD) is the leading cause of irreversible blindness in the developed world. The quality of life of both patients and families is impacted by this prevalent disease. Previously, macular...Age-related macular degeneration(AMD) is the leading cause of irreversible blindness in the developed world. The quality of life of both patients and families is impacted by this prevalent disease. Previously, macular degeneration had no known effective treatment. Today, vitamins for non-exudative AMD and intravitreal injection of medications for its exudative form are primary forms of current treatment. Modern advances in molecular science give rise to new possibilities of disease management. In the year 2003 the sequencing of the entire human genome was completed. Since that time, genes such as complement factor H, high-temperature requirement factor A1, and age-relateed maculopathy susceptibility 2 have been discovered and associated with a higher risk of AMD. A patient's genetic make-up may dictate the effectiveness of current or future therapeutic options. In addition, utilizing genetic data and incorporating it into new treatments(such as viral vectors) may lead to longer-lasting(or permanent) VEGF blockade and specific targeting of complement related genes. There have also been considerable advances in stem cell directed treatment of AMD. Retinal pigment epithelial(RPE) cells can be derived from human embryonic stem cells, induced pluripotent stem cells, or adult human RPE stem cells. Utilizing animal models of RPE and retinal degeneration, stem cell-derived RPE cells have been successfully implanted into the subretinal space. They have been injected as a cell mass or as a pre-prepared monolayer on a thin membrane. Visual recovery has been demonstrated in a retinal dystrophic rat model. Preliminary data on 2 human subjects also demonstrates possible early visual benefit from transplantation of stem cell-derived RPE. As more data is published, and as differentiation and implantation techniques are optimized, the stabilization and possible improvement of vision in individuals with non-exudative macular becomes a real possibility. We conclude that the technologic advances that continue to unfold in both genetic and stem cell research offer optimism in the future treatment of AMD.展开更多
Background The present study was undertaken to replicate the associations of representative polymorphisms in three genes （complement factor H （CFH）, complement factor B （BF） and HtrA serine peptidase 1 （HTRA1）...Background The present study was undertaken to replicate the associations of representative polymorphisms in three genes （complement factor H （CFH）, complement factor B （BF） and HtrA serine peptidase 1 （HTRA1）） with exudative age-related macular degeneration （AMD） in a Han Chinese population, and to test if the modifiable environmental factors affect AMD susceptibility associated with different type of genotype in these genes. Methods An age, gender and ethnicity matched case-control study was conducted to genotype the representative single neucleotide polymorphisms （SNPs） loci including rs1061170 and rs1410996 in CFH, rs641153 and rs4151667 in BF and rs11200638 in HTRA1 gene in 144 exudative AMD patients and 126 normal controls using PCR-RFLP and direct resequencing. The demographic characteristics and behavioral risk factors were also recorded. Allelic and genotypic associations for individual SNP and joint associations with two loci were performed. The gene-gene and gene-environment interactions were analyzed using multivariate non-conditional Logistic regression analysis. Results The C risk allele frequencies for CFH Y402H （rs1061170） in cases and controls were 12.5% and 5.4% respectively, which were much lower than those in Caucasians （P 〈0.001）. Compared with TT homozygous genotype, the CT heterozygous genotype was positively associated with AMD with odds ratio （OR） of 3.23 （1.36-5.07）. However, the population attributable risk （PAR） of C allele was only 3.3% （1.4%-4.3%）. rs1410996 was also associated with AMD independent of Y402H. The ORs of exudative AMD for individuals carrying one copy risk allele and two copy risk alleles were 2.57 （1.21-5.45） and 4.76 （2.15-10.55） respectively, with correspondent PARs of 28.3% （2.0%-40.5%） and 38.2% （21.8%-45.4%）. rs11200636 in HTRA1 was another susceptible locus for AMD and the risk homozygotes were significantly susceptible for exudutive AMD （OR=3.98, 1.88-8.43） with PAR of 38.9% （24.3%-45.8%）. Education status and cigarette smoking were also related to exudative AMD. After controlling for environmental risk factors, CFH and HTRA1 SNPs were independently associated with exudative AMD, with OR of 3.50 （1.45-8.45） for CT genotype in Y402H, 3.34 （1.33-8.36） for GG genotype in rs1410996 and 3.85 （1.58-9.42） for AA genotype in rs11200638 respectively. The interaction analysis between gene and environmental factors showed that smoking synergistically increased susceptibility of AMD for heterozygotes of rs1410996, with ORinteraction of 7.33 （Pinteraction=0.029）. Conclusions In a Han Chinese population, CFH and HTRA1 polymorphisms appear to be independently and possibly additively hereditary contributors to exudative AMD. Y402H polymorphism conferred a significant but relatively lower contribution in Chinese than in Caucasians with a low frequency of risk allele. The gene-environment interaction may be a best way to encourage those with a high genetic risk to prevent AMD by avoiding modifiable factors until there is effective treatment for AMD.展开更多
文摘Age-related macular degeneration(AMD) is the leading cause of irreversible blindness in the developed world. The quality of life of both patients and families is impacted by this prevalent disease. Previously, macular degeneration had no known effective treatment. Today, vitamins for non-exudative AMD and intravitreal injection of medications for its exudative form are primary forms of current treatment. Modern advances in molecular science give rise to new possibilities of disease management. In the year 2003 the sequencing of the entire human genome was completed. Since that time, genes such as complement factor H, high-temperature requirement factor A1, and age-relateed maculopathy susceptibility 2 have been discovered and associated with a higher risk of AMD. A patient's genetic make-up may dictate the effectiveness of current or future therapeutic options. In addition, utilizing genetic data and incorporating it into new treatments(such as viral vectors) may lead to longer-lasting(or permanent) VEGF blockade and specific targeting of complement related genes. There have also been considerable advances in stem cell directed treatment of AMD. Retinal pigment epithelial(RPE) cells can be derived from human embryonic stem cells, induced pluripotent stem cells, or adult human RPE stem cells. Utilizing animal models of RPE and retinal degeneration, stem cell-derived RPE cells have been successfully implanted into the subretinal space. They have been injected as a cell mass or as a pre-prepared monolayer on a thin membrane. Visual recovery has been demonstrated in a retinal dystrophic rat model. Preliminary data on 2 human subjects also demonstrates possible early visual benefit from transplantation of stem cell-derived RPE. As more data is published, and as differentiation and implantation techniques are optimized, the stabilization and possible improvement of vision in individuals with non-exudative macular becomes a real possibility. We conclude that the technologic advances that continue to unfold in both genetic and stem cell research offer optimism in the future treatment of AMD.
文摘Background The present study was undertaken to replicate the associations of representative polymorphisms in three genes （complement factor H （CFH）, complement factor B （BF） and HtrA serine peptidase 1 （HTRA1）） with exudative age-related macular degeneration （AMD） in a Han Chinese population, and to test if the modifiable environmental factors affect AMD susceptibility associated with different type of genotype in these genes. Methods An age, gender and ethnicity matched case-control study was conducted to genotype the representative single neucleotide polymorphisms （SNPs） loci including rs1061170 and rs1410996 in CFH, rs641153 and rs4151667 in BF and rs11200638 in HTRA1 gene in 144 exudative AMD patients and 126 normal controls using PCR-RFLP and direct resequencing. The demographic characteristics and behavioral risk factors were also recorded. Allelic and genotypic associations for individual SNP and joint associations with two loci were performed. The gene-gene and gene-environment interactions were analyzed using multivariate non-conditional Logistic regression analysis. Results The C risk allele frequencies for CFH Y402H （rs1061170） in cases and controls were 12.5% and 5.4% respectively, which were much lower than those in Caucasians （P 〈0.001）. Compared with TT homozygous genotype, the CT heterozygous genotype was positively associated with AMD with odds ratio （OR） of 3.23 （1.36-5.07）. However, the population attributable risk （PAR） of C allele was only 3.3% （1.4%-4.3%）. rs1410996 was also associated with AMD independent of Y402H. The ORs of exudative AMD for individuals carrying one copy risk allele and two copy risk alleles were 2.57 （1.21-5.45） and 4.76 （2.15-10.55） respectively, with correspondent PARs of 28.3% （2.0%-40.5%） and 38.2% （21.8%-45.4%）. rs11200636 in HTRA1 was another susceptible locus for AMD and the risk homozygotes were significantly susceptible for exudutive AMD （OR=3.98, 1.88-8.43） with PAR of 38.9% （24.3%-45.8%）. Education status and cigarette smoking were also related to exudative AMD. After controlling for environmental risk factors, CFH and HTRA1 SNPs were independently associated with exudative AMD, with OR of 3.50 （1.45-8.45） for CT genotype in Y402H, 3.34 （1.33-8.36） for GG genotype in rs1410996 and 3.85 （1.58-9.42） for AA genotype in rs11200638 respectively. The interaction analysis between gene and environmental factors showed that smoking synergistically increased susceptibility of AMD for heterozygotes of rs1410996, with ORinteraction of 7.33 （Pinteraction=0.029）. Conclusions In a Han Chinese population, CFH and HTRA1 polymorphisms appear to be independently and possibly additively hereditary contributors to exudative AMD. Y402H polymorphism conferred a significant but relatively lower contribution in Chinese than in Caucasians with a low frequency of risk allele. The gene-environment interaction may be a best way to encourage those with a high genetic risk to prevent AMD by avoiding modifiable factors until there is effective treatment for AMD.
