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1.
Understanding and documenting the process of hybridization and introgression between related species is a major focus of recent evolutionary research using molecular techniques. Many North American bison herds have cattle ancestry introduced by crossbreeding over a century ago. Molecular estimates of this ancestry have shown much higher levels for cattle mtDNA than for autosomal cattle genes. A large part of this difference appears to be the result of partial reproductive isolation between the two species where only bison bull × domestic cow crosses are successful, and all the surviving progeny are females. In addition, selection against autosomal cattle genes in bison may have contributed to differential levels of cattle ancestry. The impact of selection against cattle mtDNA and gene flow of bison mtDNA are examined to explain particular combinations of mtDNA and autosomal cattle ancestry. A bottleneck, after the level of cattle ancestry in bison was reduced to a low level, is consistent with the high variance over autosomal loci observed for cattle ancestry, and differential selection among cattle loci in bison does not need to be invoked. Further examination of the cattle genome in bison may shed light on whether these markers, or their associated regions, are indeed neutral.  相似文献   

2.
Polymorphism of 30 canine-derived microsatellites was studied in a group of 200 red foxes kept on 2 Polish farms. 22 out of 30 microsatellites were selected to study association between marker genotypes and body weight (BW), body length (BL), body circumference (BC), tail length (TL), ear height (EH), length of the right front limb (FRLL), length of the right rear limb (RRLL), length of the right front foot (FRFL) and length of the right rear foot (RRFL). A total of 112 alleles and 243 genotypes were found at 22 autosomal microsatellite loci. Three monomorphic loci deemed as uninformative were excluded from the study. The association between marker genotypes and the studied traits was analysed using general linear model (GLM) procedure and least squares means (LSM). Linkage disequilibrium (LD) was estimated to assess non-random association between microsatellite loci. Out of 19 microsatellites studied four markers showed no association with the studied traits, three markers had a significant effect on one trait, and another three markers had significant effect on two traits. Among ten microsatellites with significant effect on four economically important traits (BW, BL, BC, TL) four were associated with two characters: marker FH2613 with BW and BC, marker FH2097withBL and BC, marker ZUBECA6 with BW and BC, whereas marker REN75M10 was associated with BL and TL. The strongest LD (r2 ranged from 0.15 to 0.33) was estimated between nine loci with significant effect on economically important traits (BW, BL, BC, TL).  相似文献   

3.
The consumption of ultra-processed foods in the U.S. and globally has increased and is associated with lower diet quality, higher energy intake, higher body weight, and poorer health outcomes. This study drew on individual-level data on measured height and weight from U.S. Department of Veterans Affairs medical records for adults aged 20 to 64 from 2009 through 2014 linked to food and beverage price data from the Council for Community and Economic Research to examine the association between the price of ultra-processed foods and beverages and adult body mass index (BMI). We estimated geographic fixed effects models to control for unobserved heterogeneity of prices. We estimated separate models for men and women and we assessed differences in price sensitivity across subpopulations by socioeconomic status (SES). The results showed that a one-dollar increase in the price of ultra-processed foods and beverages was associated with 0.08 lower BMI units for men (p ≤ 0.05) (price elasticity of BMI of −0.01) and 0.14 lower BMI units for women (p ≤ 0.10) (price elasticity of BMI of -0.02). Higher prices of ultra-processed foods and beverages were associated with lower BMI among low-SES men (price elasticity of BMI of −0.02) and low-SES women (price elasticity of BMI of −0.07) but no statistically significant associations were found for middle- or high-SES men or women. Robustness checks based on the estimation of an individual-level fixed effects model found a consistent but smaller association between the price of ultra-processed foods and beverages and BMI among women (price elasticity of BMI of −0.01) with a relatively larger association for low-SES women (price elasticity of BMI of −0.04) but revealed no association for men highlighting the importance of accounting for individual-level unobserved heterogeneity.  相似文献   

4.
Increased values of multiple adiposity-related anthropometric traits are important risk factors for many common complex diseases. We performed a genome-wide association (GWA) study for four quantitative traits related to body size and adiposity (BMI, weight, waist circumference, and height) in a cohort of 1,792 adult Filipino women from the Cebu Longitudinal Health and Nutrition Survey (CLHNS). This is the first GWA study of anthropometric traits in Filipinos, a population experiencing a rapid transition into a more obesogenic environment. In addition to identifying suggestive evidence of additional single-nucleotide polymorphism (SNP) association signals (P < 10(-5)), we replicated (P < 0.05, same direction of additive effect) associations previously reported in European populations of both BMI and weight with MC4R and FTO, of BMI with BDNF, and of height with EFEMP1, ZBTB38, and NPPC, but none with waist circumference. We also replicated loci reported in Japanese or Korean populations as associated with BMI (OTOL1) and height (HIST1H1PS2, C14orf145, GPC5). A difference in local linkage disequilibrium (LD) between European and Asian populations suggests a narrowed association region for BDNF, while still including a proposed functional nonsynonymous amino acid substitution variant (rs6265, Val66Met). Finally, we observed significant evidence (P < 0.0042) for age-by-genotype interactions influencing BMI for rs17782313 (MC4R) and rs9939609 (FTO), and for a study year-by-genotype interaction for rs4923461 (BDNF). Our results show that several genetic risk factors are associated with anthropometric traits in Filipinos and provide further insight into the effects of BDNF, FTO, and MC4R on BMI.  相似文献   

5.
Objective: Increased BMI is a well‐recognized risk factor for radiographic knee osteoarthritis (rKOA); however, the contributions of the components of body composition, body fat distribution, and height to this association are not clear. Research Methods and Procedures: We examined 779 women ≥45 years of age from the Johnston County Osteoarthritis Project. Body composition was assessed using DXA, and rKOA was defined as Kellgren‐Lawrence grade ≥2. Logistic regression models examined the association between rKOA and the fourth compared with the first quartiles of anthropometric, body composition, and fat distribution measures adjusting for age, ethnicity, and prior knee injury. Results: The adjusted odds ratios and 95% confidence interval of BMI and weight were 5.27 (3.05, 9.13) and 5.28 (3.05, 9.16), respectively. In separate models, higher odds of rKOA were also found for fat mass [4.54 (2.68, 7.69)], percent fat mass [3.84 (2.26, 6.54)], lean mass [3.94 (2.22, 6.97)], and waist circumference [4.15 (2.45, 7.02)]. Waist‐to‐hip ratio was not associated with rKOA [1.45 (0.86, 2.43)], and percent lean mass was associated with lower odds [0.20 (0.11, 0.35)]. Taller women had higher odds of rKOA after adjustment for BMI [1.77 (1.05, 3.00)]. Discussion: This study confirms that BMI and weight are strongly associated with rKOA in women and suggests that precise measurements of body composition and measures of fat distribution may offer no advantage over the more simple measures of BMI or weight in assessment of risk of rKOA.  相似文献   

6.
The incidence of chronic kidney disease varies by ethnic group in the USA, with African Americans displaying a two-fold higher rate than European Americans. One of the two defining variables underlying staging of chronic kidney disease is the glomerular filtration rate. Meta-analysis in individuals of European ancestry has identified 23 genetic loci associated with the estimated glomerular filtration rate (eGFR). We conducted a follow-up study of these 23 genetic loci using a population-based sample of 1,018 unrelated admixed African Americans. We included in our follow-up study two variants in APOL1 associated with end-stage kidney disease discovered by admixture mapping in admixed African Americans. To address confounding due to admixture, we estimated local ancestry at each marker and global ancestry. We performed regression analysis stratified by local ancestry and combined the resulting regression estimates across ancestry strata using an inverse variance-weighted fixed effects model. We found that 11 of the 24 loci were significantly associated with eGFR in our sample. The effect size estimates were not significantly different between the subgroups of individuals with two copies of African ancestry vs. two copies of European ancestry for any of the 11 loci. In contrast, allele frequencies were significantly different at 10 of the 11 loci. Collectively, the 11 loci, including four secondary signals revealed by conditional analyses, explained 14.2% of the phenotypic variance in eGFR, in contrast to the 1.4% explained by the 24 loci in individuals of European ancestry. Our findings provide insight into the genetic basis of variation in renal function among admixed African Americans.  相似文献   

7.
Previous estimates of the association between body weight and wages in the literature have been conditional on education and occupation. In addition to the effect of current body weight status (body mass index (BMI) or obesity) on wages, this paper examines the indirect effect of body weight status in the late-teenage years on wages operating through education and occupation choice. Using the National Longitudinal Survey of Youth 1979 data, for women, we find that a one-unit increase in BMI is directly associated with 1.83% lower hourly wages whereas the indirect BMI wage penalty is not statistically significant. Neither a direct nor an indirect BMI wage penalty is found for men. However, results based on clinical weight classification reveal that the indirect wage penalty occurs to a larger extent at the upper tail of the BMI distribution for both men and women via the pathways of education and occupation outcomes. Late-teen obesity is indirectly associated with 3.5% lower hourly wages for both women and men. These results are important because they imply that the total effect of obesity on wages is significantly larger than has been estimated in previous cross-sectional studies.  相似文献   

8.
The prevalence of juvenile excess weight keeps growing in the more developed world (WHO, 1998). The aim of the study was to compare the prevalence of overweight and obesity in Hungarian schoolboys in 1980 and 2005.Two independent representative data collections were performed in volunteer boys aged between 6.51 and 18.50 years in the same 90 settlements of the country in 1980 (n=13,061) and 2005 (n=13,060). Height, body mass, and five skinfolds were measured by the same investigators in both instances. Overweight and obesity were estimated by using BMI (Cole et al., 2000), respectively skinfold thicknesses (Parízková, 1961).The pair-wise differences between height means were consistently significant in the 12 age groups studied. Body mass differences were not exactly proportionate with height. The boys of 2005 had significantly more relative body fat than those of 1980. The prevalence of overweight and obesity was remarkably higher in 2005.Taller height and a part of the heavier body mass in 2005 was attributed to a positive secular growth trend. The increases in BMI and fat content are negative consequences of a markedly changed lifestyle associated with inactivity and dietary habits. Because of its public health importance the trends of childhood obesity should be closely monitored.  相似文献   

9.
PCR protocols incorporating fluorescently labeled multiplexed primer combinations were developed to produce a linkage map for bison. Three hundred fifty eight microsatellite loci spanning all 29 autosomes were genotyped via 83 PCR multiplexes and nine individual amplifications. A total of 292 markers were integrated into an autosomal linkage map for bison. The sex averaged bison map (2,647 cM) was approximately 9% longer than the corresponding USDA MARC map, which covered 2,415 cM. Utilizing weaning, yearling and 17-month weights from two private bison herds, a QTL scan was conducted using the developed linkage map. LOD peaks suggestive of QTL were identified on chromosomes 2, 7, 15, and 24 for weaning weight, chromosomes 4, 14, and 15 for yearling weight and chromosomes 8, 14, and 25 for 17-month weight. Four of the identified chromosomes have conserved synteny with regions harboring growth QTL in cattle.  相似文献   

10.
Cross-sectional studies have reported significant temporal increases in prevalence of childhood obesity in both genders and various racial groups, but recently the rise has subsided. Childhood obesity prevention trials suggest that, on average, overweight/obese children lose body weight and nonoverweight children gain weight. This investigation tested the hypothesis that overweight children lose body weight/fat and nonoverweight children gain body weight/fat using a longitudinal research design that did not include an obesity prevention program. The participants were 451 children in 4th to 6th grades at baseline. Height, weight, and body fat were measured at month 0 and month 28. Each child's BMI percentile score was calculated specific for their age, gender and height. Higher BMI percentile scores and percent body fat at baseline were associated with larger decreases in BMI and percent body fat after 28 months. The BMI percentile mean for African-American girls increased whereas BMI percentile means for white boys and girls and African-American boys were stable over the 28-month study period. Estimates of obesity and overweight prevalence were stable because incidence and remission were similar. These findings support the hypothesis that overweight children tend to lose body weight and nonoverweight children tend to gain body weight.  相似文献   

11.
Nuclear DNA markers (microsatellites) were used to screen the genetic variability in the European bison population of the Bialowieza National Park, Poland. The species is listed as endangered and the Bialowieza population is the largest one worldwide. Many other herds were founded by individuals from Bialowieza. Out of 18 microsatellites, nine were polymorphic, five were found to be homozygous, and four loci did not amplify. No significant deviation from Hardy–Weinberg-equilibrium (HWE) was observed, and the average number of alleles was 2.3 per locus. Thus, the European bison is characterized by a very low level of genetic diversity, most likely resulting from the population decline in the nineteenth century. Nevertheless, allelic variability derived from the nine polymorphic loci established in this study allowed to identify each individual by its genotypic profile. This data is valuable for conservation plans of this impressive species, especially for the control of breeding success in these animals.  相似文献   

12.

Background

Obesity, typically quantified in terms of Body Mass Index (BMI) exceeding threshold values, is considered a leading cause of premature death worldwide. For given body size (BMI), it is recognized that risk is also affected by body shape, particularly as a marker of abdominal fat deposits. Waist circumference (WC) is used as a risk indicator supplementary to BMI, but the high correlation of WC with BMI makes it hard to isolate the added value of WC.

Methods and Findings

We considered a USA population sample of 14,105 non-pregnant adults () from the National Health and Nutrition Examination Survey (NHANES) 1999–2004 with follow-up for mortality averaging 5 yr (828 deaths). We developed A Body Shape Index (ABSI) based on WC adjusted for height and weight: ABSI had little correlation with height, weight, or BMI. Death rates increased approximately exponentially with above average baseline ABSI (overall regression coefficient of per standard deviation of ABSI [95% confidence interval: –]), whereas elevated death rates were found for both high and low values of BMI and WC. (–) of the population mortality hazard was attributable to high ABSI, compared to (–) for BMI and (–) for WC. The association of death rate with ABSI held even when adjusted for other known risk factors including smoking, diabetes, blood pressure, and serum cholesterol. ABSI correlation with mortality hazard held across the range of age, sex, and BMI, and for both white and black ethnicities (but not for Mexican ethnicity), and was not weakened by excluding deaths from the first 3 yr of follow-up.

Conclusions

Body shape, as measured by ABSI, appears to be a substantial risk factor for premature mortality in the general population derivable from basic clinical measurements. ABSI expresses the excess risk from high WC in a convenient form that is complementary to BMI and to other known risk factors.  相似文献   

13.
This study examined the secular changes in height, body weight, body mass index and pubertal development in male children and adolescents in Krakow (Poland) over the past 80 years, with an emphasis on the last decade (2000-2010). The survey of the population of Krakow is a continuation of observations conducted in that area for many years. The analysis aims to determine whether in the last decade Krakow still witnessed the secular trend, and what form the trend took. The body height and weight, and body mass index (BMI), of 1862 boys aged 3.5-18.5 years were analysed, against the background of a survey series from the years 1938 (N = 1801), 1971 (N = 2045), 1983 (N = 3124) and 2000 (N = 2328). The mean body height, in almost all age categories, was greater than in the past; however the final height over the last decade remained the same. The mean values of body weight and BMI increased, especially in the last decade. Also, an acceleration of puberty in boys was observed. The last 10 years saw an over 3-month decrease in the age of initial appearance of pubic hair in boys. In conclusion, the last decade saw cessation of the growing taller trend: maximum body height stabilized at approximately 179 cm, but weight and BMI increased. Also, a distinct acceleration of puberty was noticed. Lack of height increase, at the same time as weight gain and puberty acceleration, indicate a progressing developmental disharmony.  相似文献   

14.
In the European bison, Bison bonasus (L), 15 proteins coded by 20 loci have been studied. Two of these loci (Es-3 and Ca) are polymorphic and the remaining 18 are monomorphic. The average heterozygosity of bisons in Polish herds is 3.5%. The value does not differ from those found in populations of other large mammals in spite of restoration of the European bison population from a mere 13 individuals.  相似文献   

15.
The purpose of this study was to examine the interaction of childhood height and childhood BMI in the prediction of young adult BMI. The 2,802 subjects in this study were from the Child and Adolescent Trial for Cardiovascular Health (CATCH). The subjects' heights and weights were measured in 3rd grade (mean age 8.7 years) and again in 12th grade (mean age 18.3 years). The associations and interactions between height (cm) and BMI (kg/m(2)) were assessed using mixed linear regression models with adult BMI as the dependent variable. We found a significant interaction between childhood height and childhood BMI in the prediction of adult BMI (P < 0.0001). Stratification by Centers for Disease Control and Prevention (CDC) reference quintiles revealed that a positive association between childhood height and adult BMI existed only for those subjects in the top quintile of childhood BMI, within whom predicted adult BMI ranged from 27.5 (95% confidence interval = 26.4-28.6) for those in the shortest height quintile to 30.2 (95% confidence interval = 29.7-30.6) for those in the highest height quintile. Among children with high BMI levels, those who were taller, as compared to those who were shorter, had significantly higher young adult BMI levels. This pattern seems primarily due to the positive association of childhood height and childhood BMI. Clinicians should recognize the risk of excess body weight in young adulthood for all children who have a high BMI, and pay special attention to those who are tall, because their childhood height will not protect them from subsequent weight gain and elevated BMI.  相似文献   

16.
This article combines social and genetic epidemiology to examine the influence of self-reported ethnicity on body mass index (BMI) among a sample of adolescents and young adults. We use genetic information from more than 5,000 single nucleotide polymorphisms in combination with principal components analysis to characterize population ancestry of individuals in this study. We show that non-Hispanic white and Mexican-American respondents differ significantly with respect to BMI and differ on the first principal component from the genetic data. This first component is positively associated with BMI and accounts for roughly 3% of the genetic variance in our sample. However, after controlling for this genetic measure, the observed ethnic differences in BMI remain large and statistically significant. This study demonstrates a parsimonious method to adjust for genetic differences among individual respondents that may contribute to observed differences in outcomes. In this case, adjusting for genetic background has no bearing on the influence of self-identified ethnicity.  相似文献   

17.
Hispanic and African American populations exhibit an increased risk of obesity compared with populations of European origin, a feature that may be related to inherited risk alleles from Native American and West African parental populations. However, a relationship between West African ancestry and obesity-related traits, such as body mass index (BMI), fat mass (FM), and fat-free mass (FFM), and with bone mineral density (BMD) in African American women has only recently been reported. In order to evaluate further the influence of ancestry on body composition phenotypes, we studied a Hispanic population with substantial European, West African, and Native American admixture. We ascertained a sample of Puerto Rican women living in New York (n=64), for whom we measured BMI and body composition variables, such as FM, FFM, percent body fat, and BMD. Additionally, skin pigmentation was measured as the melanin index by reflectance spectroscopy. We genotyped 35 autosomal ancestry informative markers and estimated population and individual ancestral proportions in terms of European, West African, and Native American contributions to this population. The ancestry proportions corresponding to the three parental populations are: 53.3±2.8% European, 29.1±2.3% West African, and 17.6±2.4% Native American. We detected significant genetic structure in this population with a number of different tests. A highly significant correlation was found between skin pigmentation and individual ancestry (R2=0.597, P<0.001) that was not attributable to differences in socioeconomic status. A significant association was also found between BMD and European admixture (R2=0.065, P=0.042), but no such correlation was evident with BMI or the remaining body composition measurements. We discuss the implications of our findings for the potential use of this Hispanic population for admixture mapping.  相似文献   

18.
We propose a new method for using validation data to correct self-reported weight and height in surveys that do not measure respondents. The standard correction in prior research regresses actual measures on reported values using an external validation dataset, and then uses the estimated coefficients to predict actual measures in the primary dataset. This approach requires the strong assumption that the expectations of measured weight and height conditional on the reported values are the same in both datasets. In contrast, we use percentile ranks rather than levels of reported weight and height. Our approach requires the weaker assumption that the conditional expectations of actual measures are increasing in reported values in both samples. This makes our correction more robust to differences in measurement error across surveys as long as both surveys represent the same population. We examine three nationally representative datasets and find that misreporting appears to be sensitive to differences in survey context. When we compare predicted BMI distributions using the two validation approaches, we find that the standard correction is affected by differences in misreporting while our correction is not. Finally, we present several examples that demonstrate the potential importance of our correction for future econometric analyses and estimates of obesity rates.  相似文献   

19.
Genomic prediction utilizes single nucleotide polymorphism (SNP) chip data to predict animal genetic merit. It has the advantage of potentially capturing the effects of the majority of loci that contribute to genetic variation in a trait, even when the effects of the individual loci are very small. To implement genomic prediction, marker effects are estimated with a training set, including individuals with marker genotypes and trait phenotypes; subsequently, genomic estimated breeding values (GEBV) for any genotyped individual in the population can be calculated using the estimated marker effects. In this study, we aimed to: (i) evaluate the potential of genomic prediction to predict GEBV for nematode resistance traits and BW in sheep, within and across populations; (ii) evaluate the accuracy of these predictions through within-population cross-validation; and (iii) explore the impact of population structure on the accuracy of prediction. Four data sets comprising 752 lambs from a Scottish Blackface population, 2371 from a Sarda×Lacaune backcross population, 1000 from a Martinik Black-Belly×Romane backcross population and 64 from a British Texel population were used in this study. Traits available for the analysis were faecal egg count for Nematodirus and Strongyles and BW at different ages or as average effect, depending on the population. Moreover, immunoglobulin A was also available for the Scottish Blackface population. Results show that GEBV had moderate to good within-population predictive accuracy, whereas across-population predictions had accuracies close to zero. This can be explained by our finding that in most cases the accuracy estimates were mostly because of additive genetic relatedness between animals, rather than linkage disequilibrium between SNP and quantitative trait loci. Therefore, our results suggest that genomic prediction for nematode resistance and BW may be of value in closely related animals, but that with the current SNP chip genomic predictions are unlikely to work across breeds.  相似文献   

20.
Indonesians commonly perform activities on the floor that require squatting postures. It has been identified that adopting squatting postures without any proper support would gradually cause postural stress. This study examines the influence of different squatting heights to the body kinematics and subjective discomfort rating. The subjects were divided into two different body types: overweight subjects with BMI > 24.9 and normal weight subjects with BMI 18-24.9. The subjects adopted a squatting posture at no-stool condition and at the stool height of 10, 15, and 20 cm. The task was to simulate the work close to the ground level with the hip joint deeply flexed. Body segmental angular flexion (SAF) and the visual analog scale (VAS) method were selected for parameter analyses. Significant differences were found in both parameters SAF (trunk, hip, knee, and ankle) and VAS. The interaction effect was found by squatting height and the body type for SAF of the trunk (p < 0.05). However, the increasing BMI index was also found significantly affected associated with the anthropometrical characteristics for buttock height and lower limbs depth. It is suggested that normal weight subjects sit comfortably at 15 cm stool height, whereas overweight subjects preferred 20 cm stool height as a better acceptability condition in terms of overall parameter analyses.  相似文献   

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