Lysyl oxidase-like 1 polymorphisms in a southwestern Greek cataract population with pseudoexfoliation syndrome

Alexios A Panoutsopoulos,1 Vassiliki S Gartaganis,2 Marios P Giannakopoulos,1 Panos D Goumas,3 Evangelos D Anastassiou,4 Sotirios P Gartaganis1 1Department of Ophthalmology, School of Medicine, University of Patras, Achaia, Greece; 2Protein Chemistry Group, Institute of Molecular Oncology, BSRC “Al Fleming”, Vari, Greece; 3Department of Otolaryngology, Head and Neck Surgery, 4Department of Microbiology, School of Medicine, University of Patras, Achaia, Greece Purpose: The aim of this study was to determine the possible association of rs1048661 and rs3825942 single nucleotide polymorphisms (SNPs) in the lysyl oxidase-like 1 (LOXL1) gene of cataract patients from southwestern Greece with pseudoexfoliation (PEX) syndrome. Patients and methods: Ninety-three patients with PEX syndrome and 74 without PEX syndrome were recruited with the principal diagnosis being cataract. LOXL1 SNPs, rs1048661 and rs3825942, were genotyped by using polymerase chain reaction. Results: The G allele of rs1048661 was found in 96.7% in the PEX group as compared to 80.5% of non-PEX alleles (P=19×10-4; Odds ratio [OR] =5.37; 95% confidence interval [CI] =1.68–17.12). Similarly, the G allele of rs3825942 was found in 72.1% of the PEX group as compared to 41.8% of non-PEX alleles (P=4×10-5; OR =3.78; 95% CI =1.98–7.23). The T and A allele frequencies of rs1048661 and rs3825942, respectively, were underrepresented in the PEX group patients as compared to non-PEX group. Conclusion: Our data confirm previously reported association between LOXL1 polymorphisms and PEX syndrome in a southwestern Greek population. A significant association was found for the G allele of rs1048661 and rs3825942 demonstrating that the GG haplotype is a high-risk factor for the development of PEX syndrome. Keywords: exfoliative syndrome, PEX syndrome, single nucleotide polymorphism

Lack of association of the M129V polymorphism of the PRNP gene with pseudoexfoliation syndrome

Marios P Giannakopoulos,1 Anna G Antonacopoulou,2 Anastasia E Kottorou,2 Haralabos P Kalofonos,2 Sotirios P Gartaganis1 1Department of Ophthalmology, School of Medicine, 2Department of Medicine, Molecular Oncology Laboratory, Division of Oncology, University of Patras, Rion, Greece Purpose: In this study we aimed to evaluate the polymorphism at codon 129 (M129V) of the PRNP gene as a secondary risk factor for pseudoexfoliation syndrome (PEX). Methods: Two hundred and seventy-five unrelated subjects, including 156 patients with PEX and 119 unrelated control subjects, were recruited from the University Hospital of Patras, Greece. All patients and controls were of Caucasian or European ancestry. The PRNP M129V (A/G) single-nucleotide polymorphism was genotyped by real-time polymerase chain reactions. Association of the polymorphism with PEX was assessed using the two-sided Pearson’s chi-squared or Fisher’s exact test.Result: No significant difference between patients and controls was observed in terms of frequencies of alleles and genotypes of the PRNP gene.Conclusion: Polymorphism at M129V of the PRNP gene was evaluated as a secondary risk factor for developing PEX. Our results suggest that this PRNP gene polymorphism is not associated with PEX. Keywords: pseudoexfoliation syndrome, polymorphism, M129V, PEX, protein folding disorder

Alterations in conjunctival cytology and tear film dysfunction in patients with beta-thalassemia

Purpose: Patients with beta-thalassemia (beta-tha) represent a group with lifelong transfusion-dependent anemias. This study aimed to describe the conjunctival changes and tear film parameters in these patients. Methods: A total of 52 patients (104 eyes) with beta-tha major and 22 normal control subjects (44 eyes) were studied during 1999 through 2000. Tear film break-up time (BUT), Schirmer test, rose Bengal staining, and cytologic evaluation of the conjunctival epithelium were performed in all subjects. The Papanicolaou and May-Grumwald-Giemsa staining procedures were performed on all smears. Patients and control subjects were compared for tear function parameters and conjunctival changes. Results: The BUT, Schirmer test, and rose Bengal staining values were significantly lower (P < 0.001) in beta-tha patients than in control subjects. Keratinized cells were observed in conjunctival samples in 41% of patients, with a decrease in the number of goblet cells per slide in 64% of patients. In 9% of beta-tha patients, there were a slightly greater number of inflammatory cells than in control eyes. Conclusion: Ocular surface disorder of these patients was characterized by goblet cell loss and conjunctival squamous metaplasia. Our findings were correlated positively with the variable age. Epithelial damage by toxic reaction and disorder of tear quality and quantity are implicated as important factors in the pathogenesis of the ocular surface disease in beta-tha patients

Changes in HNK-1 epitope and collagen type IX in the aqueous humour of patients with pseudoexfoliation syndrome

Purpose. To investigate alterations in the proteoglycan (PG) and glycosaminoglycan (GAG) content of the aqueous humour in patients with pseudoexfoliation syndrome (PEX). Materials and methods. Aqueous humor samples were obtained during cataract surgery from nineteen patients bearing PEX features and twenty-three age-matched normal controls. Protein and IgG were quantified densitometrically after their electrophoretic separation. Collagen type IX, 3-sulphoglucuronic acid (HNK-1 epitope), biglycan and heparan sulphate proteoglycans were detected in Western and dot blots by using specific monoclonal antibodies (MAbs). The immunochemical analysis was; performed in native aqueous humour or after degradation of the glycosaminoglycans with chondroitinases. Results. Degradation of the samples with chondroitinases ABC, AC and B revealed that, in the aqueous humour from PEX eyes, collagen type IX and biglycan had a more dermatan sulphate than did normal eyes. In addition, more HNK-1 epitope was observed in PEX eyes, which after similar enzymatic treatment was found to be, located mainly in dermatan sulphate sequences. 3-sulphoglucuronic acid was a constituent of the GAG chains of the collagen type IX. We found that the electrophoretic mobility of the bands of collagen type IX and HNK-1 epitope was exactly the same in the aqueous humour of normal and PEX samples; both migrated as four bands at 120, 113, 92.6 and 56 kDa. The PGs bearing heparan sulphate were found only in normal samples. Other PGs were not detected. Conclusion. Because no significant difference was observed in the concentration of albumin and IgG in PEX and normal samples, the blood-aqueous barrier was probably not significantly compromised in PEX patients with cataract but without open-angle glaucoma. The results support the hypothesis that the pathogenesis of PEX can be linked to disturbed metabolism of GAGS and PGs