			Home About us Contact

Danish Twins (danish + twin)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

The influence of the polymorphism in apolipoprotein B codon 2488 on insulin and lipid levels in a Danish twin population

DIABETIC MEDICINE, Issue 1 2002
J. Bentzen
Abstract Aims The apolipoprotein B codon 2488 polymorphism has been associated with the metabolism of lipoproteins in subjects with Type 2 diabetes. However, no data are available on the influence of the polymorphism on insulin or glucose metabolism. This study examines the impact of the polymorphism on parameters associated with the insulin resistance syndrome in Danish twins. Methods The effect of the polymorphism on lipid, glucose and insulin measures was studied in 548 same sex twins aged 55,74 years. Results The codon 2488 polymorphism influenced fasting triglyceride levels, as well as insulin, as measured at 120 min in an oral glucose tolerance test. Subjects with the genotype T2488T had 14% higher triglyceride levels (P = 0.02) and 31% higher insulin levels (P = 0.004) than subjects with genotype C2488C. In twins discordant for genotype, the T-allele was associated with higher levels of triglyceride (P = 0.04) and insulin (P = 0.02) and lower levels of HDL-cholesterol (P = 0.04). Conclusion The T-allele of the codon 2488 polymorphism influenced parameters related to the insulin resistance syndrome, i.e. increased levels of insulin, increased levels of triglyceride and decreased levels of HDL. As the polymorphism is silent, these effects must be mediated through linkage to other polymorphisms in apolipoprotein B or other genes on chromosome 2. [source]

Evaluation of a screening instrument for essential tremor

MOVEMENT DISORDERS, Issue 7 2008
Delia Lorenz MD
Abstract To evaluate a screening instrument for essential tremor (ET) consisting of a seven-item questionnaire and a spiral drawing. A total of 2,448 Danish twins aged 70 years or more and a second sample aged 60 years or more (n = 1,684) from a population-based northern German cross-sectional study (PopGen ET) were screened for ET. Inclusion criteria were a previous diagnosis of ET, a positive answer to two or more questions of the questionnaire or a spiral rating >4 (range of scale 0,9). Three hundred thirteen of 380 positively screened and 321 negatively screened subjects were clinically examined. Definite or probable ET was diagnosed in 104 patients, possible in 86 and other tremors in 98 patients. The sensitivity of the screening instrument was 70.5%, the positive predictive value was 64.9%, the specificity was 68.2%, and the negative predictive value was 73.5%. Tremor severity correlated significantly with higher spiral scores and more positive items. More patients were identified by spiral drawing in all tremor groups. The interrater and intrarater reliability for spirals ranged from 0.7 to 0.8 using intraclass coefficient. A cluster analysis revealed that the questionnaire can be reduced to three items, about uncontrollable tremor in any body part, tremor while drinking or pouring and other family members with tremor, without loosing efficacy. We present an easy to use and reliable screening instrument that is effective to identify patients with ET but not able to exclude patients with other tremor forms. © 2008 Movement Disorder Society [source]

The effect of genetic variation in the type 1 deiodinase gene on the interindividual variation in serum thyroid hormone levels: an investigation in healthy Danish twins

CLINICAL ENDOCRINOLOGY, Issue 6 2009
Wendy M. Van Der Deure
Summary Introduction, Genetic factors have a considerable influence on serum thyroid hormone levels. The C785T and A1814G polymorphisms, located in the 3, untranslated region of the type 1 deiodinase (D1) gene have been associated with serum FT4 and rT3 levels. Objective, In healthy Danish twins, we examined the association of these polymorphisms with serum thyroid hormone levels and determined the proportion of genetic influence explained by these variants. We analysed the underlying functional mechanism by performing mRNA stability measurements and analysed the effect of these variants on D1 activity. Methods, Serum thyroid measurements and genotypes of the D1-C785T and D1-A1814G polymorphisms were determined in 1192 twins. Structural equation modelling was used to determine heritability estimates. Functional analyses were carried out in D1-transfected JEG3 cells. Results, Carriers of the D1-785T allele had 3·8% higher FT4 and 14·3% higher rT3 levels, resulting in a lower T3/T4 and T3/rT3 ratio and a higher rT3/T4 ratio. This polymorphism explained 0·87% and 1·79%, respectively, of the variation in serum FT4 and rT3. The D1-A1814G polymorphism was not associated with serum thyroid hormone levels. No differences in D1 mRNA decay rate or D1 activity were observed between wild-type D1 and the two variants. Conclusion, The D1-C785T polymorphism is consistently and significantly associated with serum thyroid hormone levels. However, the proportion of genetic influence explained by this particular polymorphism is small. No effect of the polymorphism on D1 mRNA decay rate or D1 activity was observed. The underlying functional mechanism needs to be elucidated. [source]