A common polymorphism in the 5'-untranslated region of the VEGF gene is associated with diabetic retinopathy in type 2 diabetes.

Vascular endothelial growth factor (VEGF), a major mediator of vascular permeability and angiogenesis, may play a pivotal role in mediating the development and progression of diabetic retinopathy. In the present study, we examined the genetic variations of the VEGF gene to assess its possible relation to diabetic retinopathy in type 2 diabetic patients. Among seven common polymorphisms in the promoter region, 5'-untranslated region (UTR) and 3'UTR of the VEGF gene, genotype distribution of the C(-634)G polymorphism differed significantly (P = 0.011) between patients with (n = 150) and without (n = 118) retinopathy, and the C allele was significantly increased in patients with retinopathy compared with those without retinopathy (P = 0.0037). The odds ratio (OR) for the CC genotype of C(-634)G to the GG genotype was 3.20 (95% CI 1.45-7.05, P = 0.0046). The -634C allele was significantly increased in patients with nonproliferative diabetic retinopathy (non-PDR) (P = 0.0026) and was insignificantly increased in patients with proliferative diabetic retinopathy (PDR) (P = 0.081) compared with patients without retinopathy, although frequencies of the allele did not differ significantly between the non-PDR and PDR groups. Logistic regression analysis revealed that the C(-634)G polymorphism was strongly associated with an increased risk of retinopathy (P = 0.0018). Furthermore, VEGF serum levels were significantly higher in healthy subjects with the CC genotype of the C(-634)G polymorphism than in those with the other genotypes. These data suggest that the C(-634)G polymorphism in the 5'UTR of the VEGF gene is a novel genetic risk factor for diabetic retinopathy.

Identification of a novel WFS1 mutation (AFF344-345ins) in Japanese patients with Wolfram syndrome.

Wolfram syndrome (WFS) is an autosomal recessive disorder characterized by early onset diabetes mellitus, progressive optic atrophy, sensorineural deafness and diabetes insipidus. Affected individuals may also have renal tract abnormalities as well as neurogical and psychiatric syndromes. WFS1 encoding a transmembrane protein was identified as the gene responsible for WFS. We report herein a Japanese family, of which two members had this syndrome. In the WFS1 gene of these patients, we identified a novel mutation, a nine nucleotide insertion (AFF344-345ins). In addition, one of these patients had preclinical hypopituitarism, which is an unusual feature of WFS. As only the two family members homozygous for the mutation showed WFS, these data support the notion that this mutation is the cause of WFS.

Preclinical Cushing's syndrome due to ACTH-independent bilateral macronodular adrenocortical hyperplasia with excessive secretion of 18-hydroxydeoxycorticosterone and corticosterone.

A 64-year-old woman developed hypertension and hypokalemia, due to ACTH-independent bilateral macronodular adrenocortical hyperplasia (AIMAH) with excessive secretion of 18-hydroxydeoxycorticosterone and corticosterone. Plasma cortisol did not show a diurnal rhythm, and was not suppressed by dexamethasone (8 mg). Plasma cortisol responded to ACTH and was increased by hypoglycemia without modifying ACTH levels. Radiological studies demonstrated that adrenal glands were enlarged with macronodules. Although the patient exhibited a low plasma renin activity and aldosterone levels, hypokalemia and hypertension were observed. Hormonal findings would support the hypothesis that the tumor of AIMAH originated from cells of the upper zona fasciculata.

Promoter polymorphisms of the pigment epithelium-derived factor gene are associated with diabetic retinopathy.

Pigment epithelium-derived factor (PEDF or SERPINF1), a neuroprotective and anti-angiogenic factor, may play an important role in the pathogenesis of diabetic retinopathy (DR). In 416 patients with type 2 diabetes, four polymorphisms in the PEDF SNPs were identified, rs12150053 and rs12948385 in the promoter region, rs9913583 in the 5'-untranslated region, and rs1136287 (Met72Thr) in exon 3. Based on case-control studies, rs12150053 and rs12948385, but not rs9913583 and rs1136287, were significantly associated with DR. A logistic regression analysis revealed that the TC or CC genotype of rs12150053 was a significant risk factor for DR (odds ratio 2.40, p=0.0004). The GA or AA genotype of rs12948385 was also a significant risk factor for DR. In addition, a significant interaction between the vascular endothelial growth factor (VEGF) and PEDF SNPs in the susceptibility to DR was found. These results demonstrate that the PEDF gene, in cooperation with the VEGF gene, may contribute to the development of DR.