Association between the ACE gene I/D polymorphism and osteoporosis in a Turkish population

PURPOSE

The purpose of this study was to assess the relationship between osteoporosis and the angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism in a Turkish population.

METHODS

The study group consisted of 238 unrelated women with osteoporosis and 124 unrelated healthy female controls. All participants, patients and healthy controls, were of Turkish origin from the central region of Turkey. Genomic DNA was isolated from whole venous blood samples using a commercial DNA isolation kit. The ACE gene I/D polymorphism was analysed by polymerase chain reaction and gel electrophoresis.

RESULTS

Frequencies of the DD, ID and II genotypes in the patients were 44.5, 41.2 and 14.3 %, and in the controls they were 25.0, 51.6 and 23.4 %, respectively. A significant difference was observed between patients and controls according to genotype frequency (p=0.001). D and I allele frequencies of the I/D polymorphism were 65.1 and 34.9 % in the patient group and 50.8 and 49.2 % in the control group, respectively (p<0.001).

CONCLUSION

The ACE gene I/D polymorphism could be a genetic factor associated with osteoporosis.

The effect of IL-4 and MTHFR gene variants in ankylosing spondylitis

PURPOSE

Ankylosing Spondylitis (AS) is a chronic inflammatory rheumatic disease that characteristically affects the sacroiliac joints and the spine. The exact pathogenesis of AS remains poorly understood, but genetic factors play a key role in disease development. Several genes have been consistently associated with susceptibility to AS. This study was conducted in Turkish AS patients to determine the frequency of the methylenetetrahydrofolate reductase (MTHFR) gene C677T and interleukin-4 (IL-4) gene 70 bp variable number of tandem repeats (VNTR) variants, as well as their association with clinical characteristics.

METHODS

Genomic DNA obtained from 272 persons (122 AS patients and 150 healthy controls) was used in this study. Genomic DNA was isolated and genotyped using a polymerase chain reaction (PCR)-based restriction fragment length polymorphism (RFLP) assay for the MTHFR C677T and IL-4 70 bp VNTR gene variants, which were determined using specific PCR primers.

RESULTS

There was statistically significant difference between the groups with respect to MTHFR genotype distribution (p = 0.02) and allele frequencies (p < 0.001). When we examined MTHFR and IL-4 genotype frequencies according to clinical characteristics, we found an association between the homozygous MTHFR TT genotype and ocular involvement, although this did not reach statistical significance (p = 0.02). However, we did not find any difference between the groups with respect to IL-4 genotype distribution or allele frequencies and clinical characteristics (p > 0.05).

CONCLUSION

Our findings suggest that there is an association of the MTHFR gene C677T polymorphism with the susceptibility of a person for development of AS. However, the IL-4 gene is not associated with AS within the same population.

Frequency of fragmented QRS in ankylosing spondylitis : a prospective controlled study

OBJECTIVES

Since inflammatory diseases may also cause fibrosis, we hypothesized that patients with ankylosing spondylitis (AS) may have frequent fragmented QRS complexes (fQRS) when compared to a control group.

PATIENTS AND METHODS

In this prospective study, 71 patients with AS (group 1) were compared with 42 age- and gender-matched individuals without rheumatic disease (group 2, control). fQRS was described as the presence of an additional R wave (R') or R or S wave bridging, or the presence of fragmentation on two consecutive derivations that correspond to the major coronary artery regions.

RESULTS

The mean ages of groups 1 and 2 were 37.67 ± 9.17 and 40.43 ± 11.09 years, respectively (p = 0.270). fQRS was detected in 23 AS patients (32.4%), whereas 3 patients in the control group had fQRS (7.14%). Age, gender, medication, and echocardiography results were comparable. The disease duration score was 101.37 ± 59.96 months in fQRS(+) patients; in contrast, it was 57.93 ± 30.95 months in fQRS(-) patients. This difference was of statistical significance (p = 0.046). A statistically significant difference was not determined between the fQRS(+) and fQRS(-) groups when evaluated in terms of HLAB27 (p = 0.739). In the fQRS(+) group, the mean lumbar Schober score was 2.91 ± 1.52; in patients without fQRS, it was 4.10 ± 1.40. The mean thoracic expansion test scores in the fQRS(+) and fQRS(-) groups were 1.44 ± 0.66 and 2.69 ± 1.22, respectively.

CONCLUSION

Given the higher frequency of fQRS detected in electrocardiography studies in AS patients than in the control group, cardiac fibrosis is thought to be more likely to occur in AS patients without cardiovascular disease. The presence of fQRS may be a simple and cost-effective method for predicting cardiac fibrosis in AS patients. fQRS can be a predictive marker for fibrosis in patients with AS.

The effects of calcitriol therapy on serum interleukin-1, interleukin-6 and tumour necrosis factor-alpha concentrations in post-menopausal patients with osteoporosis

Seventy post-menopausal women with osteoporosis were randomized into two groups: 40 patients received calcitriol (0.5 microg/day) and calcium (1000 mg/day); and 30 control patients received calcium (1000 mg/day) alone. Thirty healthy women formed the healthy control group. Bone mineral density (BMD) and serum interleukin (IL)-1, IL-6 and tumour necrosis factor-alpha (TNF-alpha) concentrations were measured at baseline and after 6 months of treatment. Calcitriol treatment for 6 months significantly increased BMD and reduced serum IL-1 and TNF-alpha concentrations compared with no significant changes in patients treated with calcium alone. Both treatments increased serum calcium and decreased parathyroid hormone concentrations. The healthy control group had a significantly lower IL-6 concentration than the post-menopausal women with osteoporosis. We have shown that calcitriol was an effective treatment for osteoporosis. Significant reductions in serum IL-1 and TNF-alpha concentrations suggest that, in addition to increasing the absorption of calcium, calcitriol may directly affect bone metabolism via cytokines.