Abstract
Purpose: :
Recent studies strongly support the role of genetic factors in the etiology of age-related macular degeneration (AMD). We have investigated the frequency of Tyr402His polymorphism of the CFH gene, Ser69Ala polymorphism at LOC387715, rs11200638 polymorphism of the HTRA1 gene and different ApoE alleles in Hungarian patients with AMD in order to determine disease risk conferred by these risk factors.
Methods: :
In a case-control study, we performed clinical and molecular genetic examination of 105 AMD patients and 95 unrelated age-matched healthy controls. According to disease severity, 48 patients (46%) were assigned to the early and 57 patients (54%) to the late AMD subgroup. Detailed patient history was recorded with the use of a questionnaire focusing on known risk factors for AMD.
Results: :
Carriers of at least one CFH, LOC337815 or HTRA1 risk allele were at 1.8-fold (95%CI: 1.0-3.3), 2.1-fold (95%CI: 1.2-3.7) or 2.0-fold (95%CI: 1.1-3.6) increased disease risk, respectively. In the early AMD subgroup, homozygous CFH, LOC337815 or HTRA1 polymorphisms conferred 4.9-fold (95%CI: 1.7-14.2), 7.6-fold (95%CI: 2.1-26.8) or 9.3-fold (95%CI: 2.3-37.4) greater likelihood of disease, respectively. In the late AMD subgroup, carriers of two CFH, LOC337815 or HTRA1 risk alleles were at 10.7-fold (95%CI: 3.8-31.7), 11.6-fold (95%CI: 3.2-41.3) or 13.2-fold (95%CI: 3.2-54.1) greater disease risk, respectively. Two CFH and one HTRA1 risk alleles in combination conferred 16.9-fold (95%CI: 3.6-79.2), while two HTRA1 risk alleles combined with one CFH risk allele associated with 22.5-fold (95%CI: 5.5-249.3) increased likelihood for late AMD. Neither did ApoE alleles increase disease risk nor proved to be protective. No significant association of the examined non-genetic factors and disease susceptibility could be demonstrated.
Conclusions: :
The CFH, LOC387715 and HTRA1 polymorphisms strongly associate to the development and progression of AMD. The association is more pronounced when homozygous risk alleles are present.
Keywords: age-related macular degeneration • mutations • clinical (human) or epidemiologic studies: risk factor assessment