@2024 Afarand., IRAN

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ISSN: 2252-0805    The Horizon of Medical Sciences 2017;23(3):175-180

Background
Age-related Macular Degeneration (AMD) is one of the main causes of blindness of millions of people over the age of 60 years old [1].
Previous Studies
Visual disturbance in AMD is accompanied by degeneration of retinal pigment epithelial cells (RPE) and light receptor cells sensitive to light. The damage of these cells causes chronic inflammation in the eye and ultimately an abnormal form of drusen that disrupts the function of PRE cell [2]. ... [3-13]. The exact role of CFB in the development of AMD has not yet been proven. Despite this, it has been shown that this protective CFB protein, which contains glutamine at position 32, has a hemolytic decreased activity compared to a protein containing arginine [14, 15]. … [16-17].
Aim(s)
The aim of this study was to investigate the association of polymorphism of CF3 gene rs4151667 with AMD (dry type with geographic atrophy phenotype) in northeastern population of Iran.
Research type
This study is descriptive, and cross-sectional.
Research society, place and time
This study was conducted in 2016-2017 in people over 60 years of age with dry type AMD with geographical atrophy phenotype in Gonabad City.
Sampling method and number
44 persons over 60 years of age were randomly selected.44 persons over 60 years of age were randomly selected.
Used devices&materials
From both patient and control groups, after completing the blood donation consent form, the blood was taken. Genomic DNA was extracted from 4 ml human blood using the standard DNA extraction protocol (saturated salt) [18]. Extracted DNA was amplified by Polymerase Chain Reaction (PCR) and the genotype of persons was determined using PCR-RFLP (Polymerase Chain Reaction based on Restriction Fragment Length Polymorphism) at the position of c.26T>A (Figure 1). To ensure the accuracy of the identified genotypes, a number of samples were sequenced that confirmed the results of PCR-RFLP. Statistical analysis: Frequency of each genotype in two groups was analyzed using 2x2 Contingency software and Chi-square test.
Findings by Text
Of the 44 patients, 42 (95.5%) had TT genotype and 2 (4.5%) had AT genotype, and from 50 persons in the control group, 44(88.0%) and 6 (12.0%) had AT genotype respectively. In none of the groups, there was AA genotype. The two groups were significantly different in terms of frequency of TT and AT genotypes (p<0.05). The percentage of chance for the TT genotype was about 2.8 and the frequency of the T Allele was high in the patient group compared to the control group (Table 1).
Main comparison to the similar studies
… [19-30]. In a study conducted in 2012 among southern population of Iran and Fars province, the association between G6721T polymorphism in the XRCC7 gene and AMD was studied. In this research, the subjects were classified according to the type of occupation (open environment and close environment). The results showed that the T allele of the G6721T polymorphism of the XRCC7 gene was associated with an increased risk of AMD in those exposed to sunlight [31]. … [32-33]. In a study conducted among an Indian group, there was no association between polymorphism rs4151667 of CFB gene and AMD. Therefore, the genetic effect of CFB polymorphism on exudative AMD in population that are white is important. However it is not important in Korean population [34, 35]. In different studies in Asian population (Japan, China, and Korea), no significant association was found between polymorphism rs4151667 (c.26T> A) and AMD, and the frequency of the dangerous allele for s4151667 in CFB was very low [36].... [37].
Suggestions
It is better to check the association of this gene with AMD in RNA level using more molecular testing. Also, it is recommended to study the subjects in terms of the variables of smoking and exposure to light that are important factors involved in the development of AMD.
Limitations
The limitation of this study was small number of patients.
Conclusions
Rs4151667 polymorphism CFB gene plays a significant role in the progression of AMD (dry type with geographic atrophy phenotype) in the northeastern population of Iran. The presence of TT genotype in individuals increases the probability of AMD diseases by 2.8 times that of non-TT genotypes, and AT genotype plays a protective role against this disease.
Acknowledgments
The authors of this article are very thankful to all persons in patient and control groups to collaborate on this research project.
Conflict of interest
Non-declared
Ethical Permissions
Ethical confirmation of this research was obtained from the Ethics Committee of Gonabad University of Medical Sciences with the code GMU.REC.1393.73.
Funding Sources
The funding source of this project is from the biodiversity science hub.

TABLES and CHARTS

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