scholarly journals The heritability of BMI varies across the range of BMI: a heritability curve analysis in a twin cohort

2022 ◽  
Author(s):  
Francesca Azzolini ◽  
Geir Berentsen ◽  
Hans Skaug ◽  
Jacob Hjelmborg ◽  
Jaakko Kaprio
Keyword(s):  
Repeated Measures ◽  
Molecular Genetic ◽  
Mixture Distribution ◽  
Gaussian Mixture ◽  
Genetic Effects ◽  
Twin Data ◽  
Normal Range ◽  
Genetic Studies ◽  
Mean Values ◽  
Pairwise Correlations

The heritability of traits such as body mass index (BMI), a measure of obesity, is generally estimated using family, twin, and increasingly by molecular genetic approaches. These studies generally assume that genetic effects are uniform across all trait values, yet there is emerging evidence that this may not always be the case. This paper analyzes twin data using a recently developed measure of heritability called the heritability curve. Under the assumption that trait values in twin pairs are governed by a flexible Gaussian mixture distribution, heritability curves may vary across trait values. The data consist of repeated measures of BMI on 1506 monozygotic (MZ) and 2843 like-sexed dizygotic (DZ) adult twin pairs, gathered from multiple surveys in older Finnish Twin Cohorts. The heritability curve and BMI value-specific MZ and DZ pairwise correlations were estimated, and these varied across the range of BMI. MZ correlations were highest at BMI values from 21 to 24, with a stronger decrease for women than for men at higher values. Models with additive and dominance effects fit best at low and high BMI values, while models with additive genetic and common environmental effects fit best in the normal range of BMI. Thus, we demonstrate that twin and molecular genetic studies need to consider how genetic effects vary across trait values. Such variation may reconcile findings of traits with high heritabilities and major differences in mean values between countries or over time.

scholarly journals Genetic effects on educational attainment in Hungary

2020 ◽  
Author(s):  
Péter P. Ujma ◽  
Nóra Eszlári ◽  
András Millinghoffer ◽  
Bence Bruncsics ◽  
Péter Petschner ◽  
...  
Keyword(s):  
Educational Attainment ◽  
Genetic Variants ◽  
Educational Level ◽  
Statistical Power ◽  
Association Studies ◽  
Molecular Genetic ◽  
Genetic Effects ◽  
Genome Wide Association Studies ◽  
Genetic Studies ◽  
Polygenic Scores

AbstractEducational attainment is a substantially heritable trait, and it has recently been linked to specific genetic variants by genome-wide association studies (GWASs). However, the effects of such genetic variants are expected to vary across environments, including countries and historical eras. We used polygenic scores (PGSs) to assess molecular genetic effects on educational attainment in Hungary, a country in the Central Eastern European region where behavioral genetic studies are in general scarce and molecular genetic studies of educational attainment have not been previously published. We found that the PGS is significantly associated with highest educational level attained as well as the number of years in education in a sample of Hungarian volunteers (N=829). In an English (N=976) comparison sample with identical measurement protocols the same PGS had a stronger association with educational level, but not with years in education. In line with previous Estonian findings, we found higher PGS effect sizes in Hungarian, but not in English participants who attended higher education after the fall of Communism, although we lacked statistical power for this effect to reach significance. Our results provide evidence that polygenic scores for educational attainment are valid in diverse European populations.

Vestibular Function and Motion Sickness Susceptibility: Videonystagmographic Evidence From Oculomotor and Caloric Tests

2020 ◽  
Vol 29 (2) ◽  
pp. 188-198
Author(s):  
Cynthia G. Fowler ◽  
Margaret Dallapiazza ◽  
Kathleen Talbot Hadsell
Keyword(s):  
Phase Velocity ◽  
Motion Sickness ◽  
Repeated Measures ◽  
Short Form ◽  
Vestibular Function ◽  
Slow Phase ◽  
Test Results ◽  
Normal Range ◽  
Slow Phase Velocity ◽  
Caloric Tests

Purpose Motion sickness (MS) is a common condition that affects millions of individuals. Although the condition is common and can be debilitating, little research has focused on the vestibular function associated with susceptibility to MS. One causal theory of MS is an asymmetry of vestibular function within or between ears. The purposes of this study, therefore, were (a) to determine if the vestibular system (oculomotor and caloric tests) in videonystagmography (VNG) is associated with susceptibility to MS and (b) to determine if these tests support the theory of an asymmetry between ears associated with MS susceptibility. Method VNG was used to measure oculomotor and caloric responses. Fifty young adults were recruited; 50 completed the oculomotor tests, and 31 completed the four caloric irrigations. MS susceptibility was evaluated with the Motion Sickness Susceptibility Questionnaire–Short Form; in this study, percent susceptibility ranged from 0% to 100% in the participants. Participants were divided into three susceptibility groups (Low, Mid, and High). Repeated-measures analyses of variance and pairwise comparisons determined significance among the groups on the VNG test results. Results Oculomotor test results revealed no significant differences among the MS susceptibility groups. Caloric stimuli elicited responses that were correlated positively with susceptibility to MS. Slow-phase velocity was slowest in the Low MS group compared to the Mid and High groups. There was no significant asymmetry between ears in any of the groups. Conclusions MS susceptibility was significantly and positively correlated with caloric slow-phase velocity. Although asymmetries between ears are purported to be associated with MS, asymmetries were not evident. Susceptibility to MS may contribute to interindividual variability of caloric responses within the normal range.

Assessment of nutritional status of students of medical institute according to the blood biochemical parameters

2020 ◽  
pp. 55-63
Author(s):  
Rofail Rakhmanov ◽  
Elena Bogomolova ◽  
Mariya Shaposhnikova ◽  
Mariya Sapozhnikova
Keyword(s):  
Nutritional Status ◽  
Lower Boundary ◽  
Density Lipoprotein ◽  
Blood Parameters ◽  
Medical Institute ◽  
Specific Situation ◽  
Mathematical Methods ◽  
Normal Range ◽  
Mean Values ◽  
The Mean

The biochemical blood parameters characterizing the students ’nutritional status were evaluated: protein, lipid, carbohydrate metabolism, a number of minerals. The mean values, errors of the mean, median (Me), boundary (Q) and the range of 25–75 percentiles were determined. In 9.1 % of students and 28.6 % of students, the total protein was increased. Creatinine in men was in the upper normal range, in women — at the upper limit of normal, of which 46.2 % was higher than normal. The interval Q25–75 of uric acid in students is determined in the lower normal zone. In 40.0 % of men, decreased high-density lipoprotein cholesterol (Q25–75 corresponded to 1.15–1.79), in women — below normal, Q25–75 5 was 1.3–1.5, decreased in 73.3 %. Me and Q25–75 iron were in the lower normal range; 14.1 % of men and 13.2 % of women are below normal. Me sodium and potassium at the level of the lower boundary of the norm, Q25–75 in the lower zone of the norm: in 16.0 % and 15.4 % of students the levels are reduced. Calcium is slightly above the lower limit of the norm, Q25–75–2.1–2.24, indicating an insufficient intake in the whole group; 25.0 % are below normal. The border of the 25th percentile of magnesium is at the level of the lower border of the norm, in 19.2 % it is reduced. 7.2 % lack of chlorine. Phosphorus is normal, but Q25–75 is in the upper zone; 17.9 % increased. Biochemical markers can identify individuals with metabolic disorders of nutrients. Statistical indicators — the median, the boundaries of 25–75 quartiles and their scope characterize the metabolism of macronutrients and minerals in the group and subgroups of students. Laboratory and mathematical methods can provide a basis for identifying the specific causes of these changes. For this, you can use the questionnaire method of studying the nutrition of students, possibly using the developed questionnaires for a specific situation.

scholarly journals Patient-Reported Outcomes After Complex Adult Spinal Deformity Surgery: 5-Year Results of the Scoli-Risk-1 Study

2021 ◽  
pp. 219256822098827
Author(s):  
Scott L. Zuckerman ◽  
Meghan Cerpa ◽  
Lawrence G. Lenke ◽  
Christopher I. Shaffrey ◽  
Leah Y. Carreon ◽  
...  
Keyword(s):  
Repeated Measures ◽  
Adult Spinal Deformity ◽  
Corrective Osteotomy ◽  
Leg Pain ◽  
Major Surgery ◽  
Mean Values ◽  
Self Image ◽  
Patient Reported ◽  
Spinal Deformity Surgery

Study Design: Prospective cohort. Objective: To prospectively evaluate PROs up to 5-years after complex ASD surgery. Methods: The Scoli-RISK-1 study enrolled 272 ASD patients undergoing surgery from 15 centers. Inclusion criteria was Cobb angle of >80°, corrective osteotomy for congenital or revision deformity, and/or 3-column osteotomy. The following PROs were measured prospectively at intervals up to 5-years postoperative: ODI, SF36-PCS/MCS, SRS-22, NRS back/leg. Among patients with 5-year follow-up, comparisons were made from both baseline and 2-years postoperative to 5-years postoperative. PROs were analyzed using mixed models for repeated measures. Results: Seventy-seven patients (28.3%) had 5-year follow-up data. Comparing baseline to 5-year data among these 77 patients, significant improvement was seen in all PROs: ODI (45.2 vs. 29.3, P < 0.001), SF36-PCS (31.5 vs. 38.8, P < 0.001), SF36-MCS (44.9 vs. 49.1, P = 0.009), SRS-22-total (2.78 vs. 3.61, P < 0.001), NRS-back pain (5.70 vs. 2.95, P < 0.001) and NRS leg pain (3.64 vs. 2.62, P = 0.017). In the 2 to 5-year follow-up period, no significant changes were seen in any PROs. The percentage of patients achieving MCID from baseline to 5-years were: ODI (62.0%) and the SRS-22r domains of function (70.4%), pain (63.0%), mental health (37.5%), self-image (60.3%), and total (60.3%). Surprisingly, mean values ( P > 0.05) and proportion achieving MCID did not differ significantly in patients with major surgery-related complications compared to those without. Conclusions: After complex ASD surgery, significant improvement in PROs were seen at 5-years postoperative in ODI, SF36-PCS/MCS, SRS-22r, and NRS-back/leg pain. No significant changes in PROs occurred during the 2 to 5-year postoperative period. Those with major surgery-related complications had similar PROs and proportion of patients achieving MCID as those without these complications.

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