Polymorphisms of intercellular adhesion molecule-1 (ICAM-1) in patients with diabetic retinopathy_DM type 2

1. Tenriesa
2. Budu
3. Harjoeno
4. Arief M

Department of Clinical Pathology, Faculty of Medicine, Hasanuddin University, Makassar, Indonesia.

Leukocyte adhesion to retinal vasculature of diabetic patients was reported to implicate in pathogenesis of diabetic retinopathy. Intercellular Adhesion Molecule (ICAM)-1 is one of the important molecules that plays a role in pathogenesis of diabetic retinopathy. The objectives of this study are to analyze the polymorphism of ICAM-1 gene (K469E) and to evaluate its relationship to phenotype of diabetic retinopathy in type 2 diabetic patients.
Genomic DNA of 11 patients without diabetic retinopathy as control and 23 of diabetic retinopathy (consisted of NPDR=non proliferative diabetic retinopathy (9) and PDR=proliferative diabetic retinopathy (14)) were extracted from peripheral leukocyte blood. ICAM-1 gene were amplificated by using polymerase chain reaction (PCR) method. Results of PCR were directly-sequenced to search the potition of the polymorphisms in exon target. Informed consents were performed in each subjects.

From 34 type-2 diabetes mellitus patients, we found a polymorphisms of ICAM-1 gene (K469E), with genotypes of KK469 in 21(61,8%), K469E in 11(32,4%) and EE469 in 2(5,9%). We found KK469, K469E and 469EE accordingly in 12(35,3%), 9(26,5%) , and 2(5,9%) in patients with diabetic retinopathy. While in those without retinopathy we found KK469 in 9(26,5%), and K469E in 2(5,9%). No one of our subjects without retinopathy found to have EE469. The occurance of retinopathy related to the duration of diabetes. We found the frequency of KK469 genotype is higher in retinopathy and K allele is associated with the occurance of retinopaty. The role of ICAM-1 gene polymorphim (K469E) has not been proved yet with the grading of diabetic retinopathy.

Key words : Polymorphism, intercellular adhesion molecule (ICAM)-1, diabetic retinopathy