An association of neovascular age-related macular degeneration with polymorphisms of CFH, ARMS2, HTRA1 and C3 genes in Czech population.

PURPOSE: We investigated associations between neovascular age-related macular degeneration (AMD) and rs10490924 polymorphism of ARMS2 gene (age-related maculopathy susceptibility 2), rs1061170 polymorphism of gene for complement factor H (CFH), rs2230199 polymorphism of gene for complement component C3 and rs11200638 polymorphism of gene for serine protease high-temperature requirement A1 (HTRA1) in the Czech population. METHODS: We analysed samples of DNA from 307 patients diagnosed with neovascular form of late AMD (average age: 73.7 ± 7.7 years) and 191 control subjects, recruited from patients awaiting cataract surgery (average age, 73.6 ± 8.7 years). RESULTS: HTRA1, CFH and ARMS2 genes polymorphisms were found to be related to neovascular AMD in the Czech population. All analysed polymorphisms were statistically significantly associated with neovascular AMD, with stronger associations in females than in males. In whole group, CC genotype of CFH gene polymorphism, TT genotype of ARMS2 gene polymorphism and AA genotype of HTRA1 gene polymorphism showed the greatest risk for neovascular AMD with odds ratios equal to 8.43, 10.07, 9.83, respectively (p < 0.0001). Only CG polymorphism of C3 gene showed statistically significant risk for neovascular AMD. In addition, we observed an association between waist circumference and neovascular AMD in both sexes, which further suggests the significance of excessive abdominal fat as a risk factor of AMD. We found a statistically significant association between polymorphisms in HTRA1, CFH and ARMS2 genes and neovascular AMS in the Czech population. The association was stronger in females than in males. CONCLUSION: We demonstrated a relationship between neovascular AMD and genes for HTRA1, CFH, ARMS2 and C3 in Czech population. To our knowledge, the relationship between these polymorphisms and neovascular AMD in Czech population has never been investigated before.

CHAT gene polymorphism rs3810950 is associated with the risk of Alzheimer's disease in the Czech population.

BACKGROUND: Cholinergic hypothesis of Alzheimer's disease (AD) is based on the findings that a reduced and/or perturbed cholinergic activity in the central nervous system correlates with cognitive decline in patients with Alzheimer's disease. The hypothesis resulted in the development of centrally-acting agents potentiating cholinergic neurotransmission; these drugs, however, only slowed down the cognitive decline and could not prevent it. Consequently, the perturbation of the central cholinergic signalling has been accepted as a part of the Alzheimer's aetiology but not necessarily the primary cause of the disease. In the present study we have focused on the rs3810950 polymorphism of ChAT (choline acetyltransferase) gene that has not been studied in Czech population before. METHODS: We carried out an association study to test for a relationship between the rs3810950 polymorphism and Alzheimer's disease in a group of 1186 persons; 759 patients with Alzheimer's disease and 427 control subjects. Furthermore, we performed molecular modelling of the terminal domain (1st-126th amino acid residue) of one of the ChAT isoforms (M) to visualise in silico whether the rs3810950 polymorphism (A120T) can change any features of the tertiary structure of the protein which would have a potential to alter its function. RESULTS: The AA genotype of CHAT was associated with a 1.25 times higher risk of AD (p <  0.002) thus demonstrating that the rs3810950 polymorphism can have a modest but statistically significant effect on the risk of AD in the Czech population. Furthermore, the molecular modelling indicated that the polymorphism is likely to be associated with significant variations in the tertiary structure of the protein molecule which may impact its enzyme activity. CONCLUSIONS: Our findings are consistent with the results of the meta-analytical studies of the relationship between rs3810950 polymorphism and AD and provide further material evidence for a direct (primary) involvement of cholinergic mechanisms in the etiopathogenesis of AD, particularly as a factor in cognitive decline and perturbed conscious awareness commonly observed in patients with AD.

CD36 gene is associated with intraocular pressure elevation after intravitreal application of anti-VEGF agents in patients with age-related macular degeneration: Implications for the safety of the therapy.

BACKGROUND: The wet form of age-related macular degeneration (AMD) is characterized by pathological vascularization of the outer retinal layers. The condition responds to treatment with antibodies against vascular endothelial growth factor (VEGF), but the patients receiving such anti-VEGF therapy sometimes show undesirable acute short-term increases in the intraocular pressure (IOP). The cause of this adverse effect is unknown, and here, we are testing a hypothesis that it is related to CD36 gene polymorphisms. MATERIALS AND METHODS: A group of 134 patients with AMD were given three therapeutic doses of anti-VEGF antibody (ranibizumab) at monthly intervals. Their IOP was measured immediately before and 30 min after each injection. Patients' DNA was analyzed, and the changes in IOP were matched against seven polymorphisms of the CD36 gene. RESULTS: Three polymorphisms were found to be associated with increases in IOP: rs1049673 (p = 0.006), rs3211931 (p = 0.01), and rs1761667 (p = 0.043) at the time of the third injection only. Pronounced elevations (IOP > 25 mmHg) were associated with rs1049673 polymorphism: GC genotype (p < 0.01) and CC genotype (p < 0.05); both increasing the risk 2.6-fold, the presence of C-allele conferring a 1.5-fold greater risk and with rs3211931 polymorphism: AG genotype (p < 0.01) and GG genotype (p < 0.05); increasing the risk 2.6-fold (AG) and 2.7-fold (GG). CONCLUSIONS: CD36 receptor may be involved in mediating the effects of VEGF on IOP. The findings will help to identify the patients at risk of acutely elevated IOP following the anti-VEGF therapy.

CD36 gene polymorphism is associated with Alzheimer's disease.

CD36 gene encodes a membrane glycoprotein (type B scavenger receptor) present on the surface of many types of cells and having multiple cellular functions ranging from angiogenesis to gustatory perception of fatty acids. Using a case control genetic association approach we have analyzed selected single nucleotide polymorphisms (SNP's) in a total of 859 patients with Alzheimer's disease (AD) and controls and have identified the allele A in rs3211892 polymorphism of CD36 gene as significantly increasing the risk of AD. Additionally we have investigated, in the same sample of control subjects and patients, SNP's in ApoE gene and confirmed that the previously identified AD-associated SNP's indeed increased the risk and decreased the age of onset of AD as reported by others earlier. Based on the current knowledge of CD36 biochemistry we propose that the AD risk-imparting variants of CD36 alter cholesterol homeostasis, oxidation stress or induce pathological inflammatory cascades. The SNP rs3211892 has previously been associated with heart disease and other conditions but the present study is the first to identify a significant association between variations in CD36 gene and the risk of Alzheimer's disease.