Do genetic factors contribute to the association between birth weight and blood pressure?

OBJECTIVES: To evaluate whether genetic factors contribute to the association between low birth weight and increased blood pressure among adolescents. DESIGN: Historical cohort study of twin pairs. It was evaluated whether (1) a negative association between birth weight and systolic blood pressure was found in the overall twin sample and (2) whether the intrapair difference in birth weight correlated with the intrapair difference in systolic blood pressure-thereby controlling for the effect of genetic factors (all in monozygotic and on average half in dizygotic pairs). SETTING: The Minnesota Twin Family Study. PARTICIPANTS: 1311 pairs of adolescent twins. MAIN RESULTS: A negative association between birth weight and systolic blood pressure was retrieved in the overall sample. The regression coefficient after controlling for current weight was -1.88 mm Hg/kg (SE 0.61), which corresponds to results from previous studies of singleton adolescents. The regression coefficient fell to -0.64 mm Hg/kg (SE 0.86) when the intrapair analyses were used. The largest reduction was observed among monozygotic twins: from -2.44 mm Hg/kg (SE 0.75) in the overall monozygotic twin sample to -1.06 mm Hg/kg (SE 1.14) in the analyses of the within monozygotic pair differences. CONCLUSION: The association between low birth weight and increased blood pressure later in life is well established. "The fetal programming hypothesis" suggests that the association is caused by intrauterine malnutrition while a new hypothesis "the fetal insulin hypothesis" proposes that genetically determined insulin resistance also contributes significantly to the association. A recent twin study of middle aged twins showed no evidence for an influence of genetic factors while this larger study provides support for the fetal insulin hypothesis: the association between birth weight and blood pressure attenuated among adolescents when genetic factors were controlled. Together this suggests an important contribution of genetic factors to the association between fetal growth and systolic blood pressure in adolescence.     

Birth weight and body composition in young women: a prospective twin study

BACKGROUND: The intrauterine environment may be critical for the development of obesity. Alternatively, the same genetic factors may influence both birth weight and adult body composition. OBJECTIVE: We evaluated the association between birth weight and adult body composition in female twins, which allowed us to control for maternal and genetic influences. DESIGN: Of 447 twin pairs randomly selected from the East Flanders Prospective Twin Survey, 238 pairs, aged 18-34 y, participated. Adult body mass, height, and lean body mass were measured, and the body mass index (BMI), waist-to-hip ratio, and sum of skinfold thicknesses were calculated. The twins were considered as individuals and pairs. RESULTS: When the twins were considered as individuals, twins who were heavier at birth were taller (3.3 cm/kg greater birth weight) and slightly heavier (1.13 kg/kg greater birth weight) as adults than were lighter twins. They also had more lean body mass and less subcutaneous and abdominal fat at birth. Pairwise comparison showed that for every level of intrapair birth weight difference (> or = 5%, > or = 10%, and > or = 15%), the twin who was heavier at birth was taller in adult life (0.8, 1.2, and 2.0 cm, respectively). When the intrapair birth weight difference exceeded 15%, the heavier twin was also heavier (3.1 +/- 6.08 kg) as an adult than her much lighter sister. CONCLUSION: Birth weight accounts for some of the differences in adult body composition between twins.     

Intrapair comparisons of diet and food preference in adult twins

OBJECTIVES: An investigation was conducted on the influence of genetic and lifestyle factors related to the determination of eating behavior of human beings. The objective was to obtain information about lifestyle factors that may help health professionals intervene in terms of the prevention of diet-related diseases. METHODS: The subjects were 180 pairs of adult twins aged over thirty, comprising of 134 monozygotic (MZ) and 46 dizygotic (DZ) pairs. Every subject was given an interview concerning dietary habits, food preference, food intake, as a part of medical examination. The intake of food containing salt and fat, the intake of food meals, the frequency of daily meals, and the frequency of eating 18 sorts of food were assessed on an individual basis, with a questionnaire on nutrition. The expected and observed values of intrapair concordance rates were calculated, and compared within each zygosity, using the chi-square test. RESULTS: Significant differences between the expected and observed for intrapair concordance rates were shown with monozygotic twins, regarding every category of question. Comparing MZ pairs who had lived apart before their twenties with the other MZ pairs, the latter had a tendency to show significant differences between the expected and observed values of intrapair concordance rate, regarding every category of question. In each case, the observed values were higher than the expected values. CONCLUSIONS: The study implied that both genetic and lifestyle factors influence the determinants of eating behavior of human beings. This finding shows the importance of understanding individual characteristics of food preference and eating behavior for intervention regarding lifestyle factors for prevention of diet-related diseases.     

Birth weight and risk of angina pectoris: analysis in Swedish twins

Objective: Intrauterine nutrition approximated by birth weight has been shown to be inversely associated with risk of coronary heart disease (CHD). By investigating the association within twin pairs discordant for disease, the influence of genetic and early environmental factors is substantially reduced. Methods: We have investigated the association between birth weight and angina pectoris in same-sexed twins with known zygosity included in the population-based Swedish Twin Registry. Self-reports of birth weight and angina pectoris were collected in a telephone interview between 1998 and 2000. The cohort analyses were based on 4594 same-sexed twins, and the within-pair analyses included 55 dizygotic and 37 monozygotic twin pairs discordant for angina pectoris. Odds ratios (OR) and 95% confidence intervals (CI) were calculated by logistic regression. Results: Compared with birth weight between 2.0 and 2.9 kg, low birth weight (<2.0 kg) was associated with increased risk of angina pectoris in the twin cohort, (OR: 1.46; 95% CI: 1.14–1.87), but after adjustment for potential confounders the risk decreased, and did not reach significance. Within twin pairs discordant for angina pectoris, low birth weight was significantly associated with increased risk of angina pectoris within dizygotic twins (adjusted OR: 5.73; 95% CI: 1.59–20.67), but not within monozygotic twins (adjusted OR: 1.20; 95% CI: 0.40–3.58). Conclusions: The results suggest that genetic differences associated with foetal growth and adult risk of CHD may have affected previously reported associations between birth weight and CHD.     

58对孤独症谱系障碍双胞胎临床特点及同病率分析

目的 分析58对孤独症谱系障碍(ASD)双胞胎临床特点及同病率,以及其遗传规律和影响因素。方法 收集1999-2015年就诊于中山大学附属第三医院发育行为中心的ASD双胞胎,对随访的58对ASD双胞胎临床资料进行总结分析,其中至少1名双胞胎诊断为ASD,通过统计描述,使用R软件进行分析同病率。结果 双胞胎出生体重较低,胎龄较小,围生期有较多高危因素;同卵双胞胎的同病率为73.68%,异卵双胞胎的同病率为12.82%,差异具有统计学意义(χ²＝18.81,P<0.001)。结论 ASD双胞胎同卵双胞胎具有较高的同病率,提示遗传因素是其重要病因。     

成年双生子血尿酸遗传度研究

目的 用双生子研究方法 对成年人血尿酸的遗传度进行估计.方法 从青岛双生子库募集成年双生子.测量身高、体重和血尿酸.相同性别的双生子采用16个多态标记进行卵型鉴定.通过校正年龄、性别和BMI,来构建结构方程模型估计遗传度.结果 共收集687对双生子数据,其中同卵双生子420对,异卵双生子267对.经平方根转换后,男性血尿酸水平(17.47±1.91)略高于女性(15.22±1.70)(P＜0.0001),通过校正年龄、性别和BMI后双生子血尿酸的组内相关系数分别为,同卵双生子0.70、异卵双生子0.40.运用性别限制模型进行拟合,最佳模型AE模型,加性别遗传因素和特殊环境因素共同作用血尿酸的水平.血尿酸的遗传度为70.5%(95%CI:65.9～74.6),特殊环境因素占29.5%(95%CI:25.4～34.2).结论 遗传因素是影响样本双生子血尿酸水平的主要因素.     

Lifestyle factors in monozygotic and dizygotic twins

In examining genetic influences on biological variables using twins, it may be important to examine the distribution between and within twin pairs of demographic and lifestyle factors that may themselves affect the biological variable being studied. We explored the distribution of demographic and lifestyle factors that may affect blood lipid levels or ischaemic heart disease (IHD) risk among a sample of 106 monozygotic (MZ) and 94 like-sex dizygotic (DZ) twin pairs. In our sample, MZ twins were statistically significantly different from DZ twins only in marital status, cigarette smoking habits, and the ratio of polyunsaturated to saturated fat (P:S ratio) in their dietary intake. The latter variable was among many dietary variables examined (using 4-day weighed food diaries), and the size of the difference in intake was small. When comparisons were made of the similarities within twin pairs, we found members of MZ twin pairs to be statistically significantly closer than DZ twins in educational achievement, occupation, cigarette smoking, and exercise habits, and the number of days a week on which alcohol was consumed. These last three variables were consistently closer among twins with closer contact than among those with a smaller degree of current shared environment. For 12 of the 13 nutrients examined, the within-pair correlations were higher for MZ than for DZ twins, although our test for significant genetic variance showed statistical significance only for intake of complex carbohydrates. We conclude that MZ twins share demographic and lifestyle factors that might influence the risk of IHD and blood lipid levels to a greater degree than do DZ twins, although it is difficult to say if these similarities in lifestyle result from genetic influences or not. Nevertheless, ascribing differences between correlations in MZ and DZ twin pairs for lipid levels as being purely "genetic"--as implicit in conventional measures of heritability--is likely to overestimate the influence of genetic factors.     

Heritability of body size and muscle strength in young adulthood: a study of one million Swedish men

Moderate heritability for skeletal muscle strength has been reported in twin studies, but genetic co-variation between muscle strength at different parts of body and body size is not well known. Further, representativeness of twin cohorts needs to be critically evaluated. Height, weight, elbow flexion, hand grip and knee extension strength were measured in young adulthood in 1,139,963 Swedish men born between 1951 and 1976. We identified 154,970 full-brother pairs and 1582 monozygotic (MZ) and 1864 same-sex dizygotic (DZ) complete twin pairs. The data were analyzed using quantitative genetic modeling for twin and family data. Twins compared to singletons and MZ twins compared to DZ twins were shorter, lighter and had lower muscle strength. In singletons, there was more variation in weight and the strength measures compared to twins with known zygosity but not when compared to twins with unknown zygosity. Full-sib correlations for these traits were lower than DZ correlations. Additive genetic factors explained 81% of variation in height, 59% in body mass index and 50-60% in the strength measures. Additive genetic correlations varied from 0.13 between height and elbow flexion strength to 0.78 between elbow flexion and hand grip strength. Our results suggest that extra variation may exist in general populations not found in twin samples, probably because of selection due to non-participation. This may have inflated heritability estimates in previous twin studies. Nonetheless, we showed that genetic factors affect muscle strength and part of these genes are common to different strength indicators and body size.     

Major genetic susceptibility for venous thromboembolism in men: a study of Danish twins

BACKGROUND: Although several genetic determinants (mutations or polymorphisms) have been associated with increased risk of venous thromboembolism, the overall influence of genetic factors on this disease is unknown. METHODS: We linked the Danish Twin Registry, which includes twins born 1870-1953, with the Danish National Registry of Patients, comprising all hospitalizations in Denmark since 1977. We then determined the risk of venous thromboembolism as determined from discharge diagnosis. RESULTS: We identified 26,982 twins who were alive on 1 January 1977, and computed measures of familial and genetic association of venous thrombotic disorders. Individuals were classified according to zygosity and hospitalization with venous thromboembolism. Since 1977, 678 twins were hospitalized with an episode of venous thromboembolism. Of these, only 545 pairs (281 male pairs and 264 female pairs) were alive in 1977. For men, the concordance rates for mono- and dizygotic twin pairs, respectively, were 0.22 (95% confidence interval = 0.14 to 0.30) and 0.08 (0.04-0.12). The odds ratio (interpreted as the relative risk of venous thromboembolism for one twin, given venous thromboembolism in the partner twin) was 13.5 (7.3-24.8) among monozygotic twins and 3.8 (1.8-8.3) among dizygotic twins. The respective correlations for venous thromboembolism were 0.55 (0.38-0.70) and 0.26 (0.09-0.42). The proportion of the variance attributable to genetic effects on venous thromboembolism in males was 55% (39%-68%). The remaining variation could be attributed to men's nonfamilial environments. In contrast, for women there was no intra-twin pair similarity for venous thromboembolism. CONCLUSIONS: We found differences in genetic susceptibility to venous thromboembolism between the sexes, with genetic factors playing a substantially stronger role in males than in females.     

The role of genetic and environmental factors in the association between birthweight and blood pressure: evidence from meta-analysis of twin studies

BACKGROUND: An inverse association between birthweight and later blood pressure has been found in many studies in singletons. Twin studies have been used to examine whether genetic factors or family environment could account for this association. METHODS: A systematic review identified 10 studies covering 3901 twin pairs. Meta-analysis of regression coefficients for the association between birthweight and systolic blood pressure was carried out for unpaired versus paired associations and for paired associations in dizygotic versus monozygotic pairs. RESULTS: After adjustment for current weight or body mass index (BMI), the difference in systolic blood pressure per kg birthweight was -2.0 (95% CI: -3.2, -0.8) mmHg in the unpaired analysis and -0.4 (95% CI: -1.5, 0.7) mmHg in the paired analysis in the same subjects. In the paired analysis by zygosity, in all twins the coefficients were -0.7 (95% CI: -2.3, 0.8) mmHg in dizygotic pairs and -0.8 (95% CI: -2.1, 0.4) mmHg in monozygotic pairs, but in studies which included zygosity tests the coefficients were -1.0 (95% CI: -3.3, 1.6) mmHg in dizygotic pairs and -0.4 (95% CI: -1.9, 1.3) mmHg in monozygotic pairs. CONCLUSIONS: The attenuation of the regression coefficient in the paired analysis provides support for the possibility that factors shared by twins contribute to the association between birthweight and blood pressure in singletons. Comparison of paired analysis in monozygotic and dizygotic pairs could not provide conclusive evidence for a role for genetic as opposed to shared environmental factors.     

双胎儿童孤独症谱系障碍广义遗传度与临床评估结果的影响因素研究

目的分析36对双胎儿童的孤独症谱系障碍(ASD)的同患率、广义遗传度,建立双胎回归模型,探讨随访资料中临床评估结果的影响因素。方法收集2016-2018年就诊于复旦大学附属儿科医院的部分双胎儿童,纳入标准:双胎至少一胎为ASD患儿,或双胎均为正常发育(NT)儿童,收集儿童的一般情况,采用孤独症诊断观察量表(ADOS)和Griffiths精神发育量表(GMDS)对儿童的社交能力和总发育商进行评估,使用R统计建模语言和双胎分析软件包mets建立模型。结果在36对双胎中,同卵双胎ASD共患率为66.7%,异卵双胎ASD共患率则为16.7%;ASD风险因素的最佳拟合为包含性别和体重的AE模型,广义遗传度接近90.4%(95%CI:65.2%~115.7%),但临床协变量和遗传因素对ASD预测的作用均不显著;孤独症诊断观察量表中重复和刻板行为(ADOS-RRB)的最优模型为加入自闭症诊断、体重、受孕方式与患儿年龄在内的AE遗传模型,孤独症诊断观察量表中社交情感(ADOS-SA)的最优拟合模型为引入性别、患儿年龄、母亲教育程度与受孕方式在内的CE遗传模型,Griffiths精神发育量表中总发育商(GMDS-DQ)的最优模型为ASD诊断、是否早产、性别在内的CE遗传模型,非共享环境因素对ADOS-RRB(P=0.000 2)、ADOS-SA(P<0.000 1)以及GMDS-DQ(P<0.000 1)的影响差异均有统计学意义。结论遗传因素是ASD发生的重要因素,非共享环境因素与ASD临床评估结果具有一定相关性。     

Genetic effects on weight change and food intake in Swedish adult twins

BACKGROUND: Obesity is influenced by genetic and environmental factors. Additionally, synergistic effects of genes and environments may be important in the development of obesity. OBJECTIVE: The aim of this study was to test for genetic effects on food consumption frequency, food preferences, and their interaction with subsequent weight gain. DESIGN: Complete data on the frequencies of consumption of 11 foods typical of the Swedish diet were available for 98 monozygotic and 176 dizygotic twin pairs aged 25-59 y who are part of the Swedish Twin Registry. The data were collected in 1973 as part of a questionnaire study. Body mass index was measured in 1973 and again in 1984. RESULTS: There was some evidence that genetic effects influenced the frequency of intake of some foods. Similarity among monozygotic twins exceeded that among dizygotic twins for intake of flour and grain products and fruit in men and women, intake of milk in men, and intake of vegetables and rice in women, suggesting that genes influence preferences for these foods. Analyses conducted for twins reared together and apart also suggested greater monozygotic than dizygotic correlations, but cross-twin, cross-trait correlations were all insignificant, suggesting that the genes that affect consumption frequencies are not responsible for mediating the relation between the frequency of intake and weight change. CONCLUSIONS: Genetic effects and the frequency of intake are independently related to change in body mass index. However, there was no suggestion of differential genetic effects on weight gain that were dependent on the consumption frequency of the foods studied.     

青春期女性血清瘦素及可溶性瘦素受体的双生子研究

目的探讨青春期女性血清瘦素及可溶性瘦素受体的变化趋势,估计遗传与环境因素的相对效应。方法以学校登记为基础募集6～18岁女性双生子180对,其中同卵双生子132对、异卵双生子48对,按Tanner标准进行青春发育分期,测定空腹血清瘦素和可溶性瘦素受体浓度。结果青春期女性血清瘦素浓度随青春期进展而显著增高,可溶性瘦素受体则呈显著下降趋势。二者的综合作用使得游离瘦素指数随青春期进展持续增高,7～9岁和12—14岁增高尤为显著,分别为10．1～32．3和41．8～82．1;瘦素和游离瘦素指数与各体格指标呈显著正相关(r值为0．54～0．76),而可溶性瘦素受体则与各指标呈显著负相关(r值为-0．23～-0.42);各指标组内相关系数均为同卵双生子大于异卵双生子,而偶内差和相似度系数则异卵双生子大于同卵双生子,瘦素、可溶性瘦素受体和游离瘦素指数的遗传度分别为0．37、0.84和0.46。结论7～9岁女孩游离瘦素指数的快速增长可能对青春期的启动起促进作用,而12—14岁的突增可能对即将到来的月经初潮起预示作用。青春期女孩血清游离瘦素指数同时受遗传与环境因素的影响,瘦素受环境因素的影响较大,可溶性瘦素受体则受遗传因素的影响较强。     

Motor development of Japanese twins in childhood as reported by mothers

Objective Twins tend to lag behind singletons in their motor development, though the causes of this appear to be complicated and are not yet fully understood. The present study was performed to clarify the factors associated with the motor development of twins. Methods The twins in the first group consisted of school applicants, including 1131 twin pairs, and the second group consisted of children of members of several maternal associations, and included 951 pairs. All data were gathered by questionnaire survey, and six gross-motor development milestones were analyzed in individuals or pairs. Results Relative to general population norms in Japan, twins tended to be delayed in reaching several motor development milestones. Stepwise regression analysis showed that of all the variables measured, gestational age was the most influential on all six milestones. Birthweight was also influential on most milestones. Other factors affecting motor development milestones were parity for ‘sitting without support,’ ‘pulling up to a standing position,’ and ‘walking without support,’ and zygosity for ‘walking without support.’ In these cases, longer gestational age, heavier birthweighf, primiparity, and dizygosity showed a tendency toward earlier attainment of development. Motor development within pairs was more similar in monozygotic pairs compared with dizygotic pairs regarding each item, suggesting genetic contributions. Conclusion The results of the present study showed specific and nonspecific factors that affect motor development of twins. These findings should prove useful in understanding the motor development of twin children and help clinicians to refine maternal and child health care for multiple-birth children.     

The correlation of fecundability among twins: evidence of a genetic effect on fertility?

BACKGROUND: Numerous rare genetic conditions are known to influence fecundability in both males and females. It is less clear to what extent more subtle genetic differences influence fecundability on a population level. METHODS: In 1994 a population-based survey was conducted among Danish twins born 1953-1982. Fecundability was assessed as the waiting time to pregnancy at the first attempt to achieve a pregnancy. RESULTS: The reported time to pregnancy for males was slightly shorter than for females but there were no sex differences in intrapair similarity. We found an intrapair correlation in time to pregnancy for 645 monozygotic twin pairs (r = 0.22; 95% confidence interval = 0.12 to 0.32), but no intrapair correlation for 826 like-sex dizygotic twin pairs (r = 0.00; 95% confidence interval = -0.09 to 0.10). CONCLUSIONS: The correlation in time to pregnancy for monozygotic twins suggests genetic factors, although similarities in reporting behaviors could also be contributing to the correlation. The lack of correlation in time to pregnancy for dizygotic twins indicates that possible genetic factors of importance for fecundabililty are acting nonadditively. Hence, it may prove difficult to identify specific gene variants that influence fecundability on a population level if their effects depend on gene-gene interactions.     

遗传与环境因素对女性青春期性征发育的影响

目的探讨遗传与环境因素对女性青春期性征发育的影响,为进一步深入研究女性青春期发育提供依据。方法以学校登记为基础,募集6~18岁女性双生子180对,其中单卵双生(MZ)132对,二卵双生(DZ)48对,按Tanner标准进行青春发育分期,询问有无月经初潮及月经初潮年龄。结果乳房开始发育的年龄为9~12岁,阴毛开始发育的年龄集中在9~13岁,月经初潮年龄多集中在11~13岁。月经初潮、性征发育一致率均为MZ>DZ,月经初潮的遗传指数为0.71,乳房和阴毛发育的遗传指数分别为0.34,0.45。月经初潮年龄的组内相关系数MZ>DZ(P<0.001),偶内均方MZ相似文献   

双生子艾森克人格与血液生化指标的相关性研究

[目的 ]了解双生子艾森克人格特点及遗传因素对艾森克人格的影响 ,探讨血液生化指标与艾森克人格的相关性。 [方法 ] 2 0 0 1年 12月对青岛市 89对 2 4岁以上的双生子 (同卵 5 5对 ,异卵 3 4对 )进行艾森克人格测试 ,检测 3 7项血液生化指标 ,并进行相关分析。 [结果 ]同卵双胞胎之间在N(情绪稳定性 )因子的相关系数高于异卵双胞胎 ,N因子的遗传度为 0 45。人格因素中只有N因子与几项生化指标有相关关系 (r <0 3 0 )。 [结论 ]艾森克人格因素中的N因子受遗传作用的倾向较大 ,血液生化指标水平并不决定人的个性心理特征。     

利用结构方程模型计算成年双生子饮酒遗传度的研究

目的 分析遗传和环境因素对饮酒的影响。方法 对2015-2018年中国双生子登记系统募集的9 231对成年同性别双生子,利用结构方程模型对饮酒相关变量进行拟合,估计遗传因素和环境因素对其的影响。结果 共纳入9 231对双生子进行分析,其中同卵双生子6 085对。同卵双生子年龄（36.91±13.07）岁,男性占56.80%;异卵双生子年龄（35.22±12.48）岁,男性占55.91%。双生子高风险饮酒者共350人,占1.90%,中风险饮酒者共367人,占1.99%。中风险饮酒受加性遗传、双生子共享环境及各自环境的影响,遗传度为24.3%（95% CI：0～56.8%）,共享环境可解释50.7%（95% CI：20.4%～79.0%）,特殊环境可解释24.9%（95% CI：18.3%～36.5%）。而高风险饮酒则主要受双生子共享环境及各自特殊环境的影响,共享环境可解释75.6%（95% CI：69.6%～80.8%）,特殊环境可解释24.4%（95% CI：19.2%～30.4%）。中高风险饮酒的遗传度具有一定的性别差异,男性中遗传度为30.8%（95% CI：9.8%～53.5%）,在女性中则主要受到环境的影响。结论 中高风险饮酒行为主要受环境影响,有一定的性别差异,且随着饮酒量的增加,环境对于饮酒行为的影响作用更趋显著。     

Genetic and environmental influences on residential location in the US

We used a classical twin design and measures of neighborhood walkability and social deprivation, using each twin's street address, to examine genetic and environmental influences on the residential location of 1389 same-sex pairs from a US community-based twin registry. Within-pair correlations and structural equation models estimated these influences on walkability among younger (ages 18-24.9) and older (ages 25+) twins. Adjusting for social deprivation, walkability of residential location was primarily influenced by common environment with lesser contributions of unique environment and genetic factors among younger twins, while unique environment most strongly influenced walkability, with small genetic and common environment effects, among older twins. Thus, minimal variance in walkability was explained by shared genetic effects in younger and older twins, and confirms the importance of environmental factors in walkability of residential locations.     

Comparison of the Coincidence of Osteoporosis,Fracture, Arthritis Histories,and DEXA T-Score between Monozygotic and Dizygotic Twins: A Cross-Sectional Study Using KoGES HTS Data

We explored the genetic and environmental inter-relationships among osteoporosis, fracture, arthritis, and bone mineral density concordance in monozygotic twins compared to those in dizygotic twins. This cross-sectional research assessed data of 1032 monozygotic and 242 dizygotic twin pairs aged >20 years included in the Healthy Twin Study data of the Korean Genome and Epidemiology Study between 2005 and 2014. Outcomes of interest included illness concordance and absolute differences in dual-energy X-ray absorptiometry (DEXA) T-scores. We found comparable concordances of osteoporosis, fractures, osteoarthritis, and rheumatoid arthritis between monozygotic and dizygotic twins. Medical histories of osteoporosis, fractures caused by accident or falling, osteoarthritis, and rheumatoid arthritis were not distinct between monozygotic and dizygotic twins. Accidental fracture occurrence in both monozygotic twins showed significantly lower odds than that in dizygotic twins. Genetic influence on liability to fracture risk might thus be maintained. DEXA T-scores for bone mineral density indicated more comparable tendencies within monozygotic twin pairs than within dizygotic ones, suggesting the relative importance of genetic contribution to bone mineral density. The relative importance of genetic factors in bone mineral density is sustained between monozygotic twins; overt disease expression of osteoporosis, fractures, or arthritis may be affected by environmental factors.