Study Of Chinese Children Research Articles

Independent and joint associations of multiple metals exposure with vital capacity index: a cross-sectional study in Chinese children and adolescents.

The current study aimed to explore the relationships between urinary metals and vital capacity index (VCI) in 380 children and adolescents in Northeast China using a variety of statistical methods. A cross-sectional survey was conducted among 380 children and adolescents in Liaoning Province, China. To assess the relationships between urinary metals and VCI, Elastic-net (ENET) regression, multivariate linear regression, weighted quantile sum (WQS), bayesian kernel machine regression (BKMR) and quantile-based g computation (qgcomp) were adopted. The ENET model selected magnesium (Mg), vanadium (V), manganese (Mn), arsenic (As), tin (Sn) and lead (Pb) as crucial elements. In multiple linear regression, we observed urinary Pb, Mn was negatively correlated with VCI individually in both total study population and adolescents (all p values < 0.05) in the adjustment model. The WQS indices were negatively related with VCI in total study population (β=-3.19, 95%CI: -6.07, -0.30) and adolescents (β=-3.46, 95%CI: -6.58, -0.35). The highest weight in total study population was Pb (38.80%), in adolescents was Mn (35.10%). In the qgcomp, Pb (31.90%), Mn (27.20%) were the major negative contributors to the association in the total population (β=-3.51, 95%CI: -6.29, -0.74). As (42.50%), Mn (39.90%) were the main negative contributors (β=-3.95, 95% CI: -6.68, -1.22) among adolescents. The results of BKMR were basically consistent with WQS and qgcomp analyses. Our results indicated that Pb and Mn were priority toxic materials on VCI. The cumulative effect of metals was negatively related to VCI, and this relationship was more pronounced in adolescents.

The impact of family socioeconomic status on parental involvement and student engagement during COVID-19 in promoting academic achievement: A longitudinal study in Chinese children

With a three-wave longitudinal design, the current study examined the impact of family socioeconomic status (SES) on parental involvement and student engagement in promoting children’s academic achievement during the coronavirus disease 2019 (COVID-19) pandemic. We recruited data from 246 mother–primary school student dyads, and the mean age of children at Wave 1 was 10.57 ± 0.97 years (range = 9–13 years). The academic achievement of these children was measured both before and after school closures. Family SES, parental involvement, and student engagement were assessed during the school closures. The results indicated that family SES could predict children’s later academic achievement after accounting for their prior academic achievement and other demographics (i.e., the significant total effect in the model). Moreover, parental involvement and student engagement played chain-mediating roles in the effect of family SES on children’s later academic achievement. Neither parent involvement nor student involvement alone mediated the relationships between family SES and subsequent academic achievement. Suggestions are provided to minimize the negative impact of low family SES on children’s academic achievement during pandemics.

Sports Participation and Academic Performance in Primary School: A Cross-Sectional Study in Chinese Children.

All study participants were asked to self-report their sociodemographic factors (e.g., sex, grade, age), independence, and outcomes. Alongside that, a self-reported questionnaire was used to assess participation in sports and academic performance of three core subjects in China's schooling system (Chinese; math; English; from A to F, with A indicating the best academic performance). An ordered logistic regression, with an odds ratio (OR) at 95%CI confidence interval, was performed to examine the association between sports team participation and academic performance. The final analysis included 27,954 children aged 10-14. Children in the fifth and sixth grades accounted for 50.2% and 49.8%. Chinese, math, and English academic performance were positively correlated with participation in sports. Compared with students who never participate in sports, those students who participate in sports 1-3 times a month, 1-2 times a week, and 3 or more times a week, were more likely to achieve better grades. In terms of math, compared with students who never participate in sports, those students who participate in sports 1-3 times a month, 1-2 times a week, and 3 or more times a week, were more likely to achieve better grades. Regarding English, compared with students who never participate in sports, those students who participate in sports 1-3 times a month, 1-2 times a week, and 3 or more times a week, were more likely to achieve better grades. Consistent with previous studies, the current study confirms the positive effect of sports participation on children's academic performance. For an academic-related outreach, gender-, grade- and area-specific strategies should be considered in future research.

Life events and parent style for mental health in children: a cross-sectional study.

Life events and parenting styles might play an important role in children's mental health. This study aims to explore how life events and parenting styles influence children's mental health based on a Chinese sample. A total of 3535 participants had at least one mental disorder (positive group), while a total of 3561 participants had no mental disorders (negative group). The Child Behavior Checklist (CBCL), Adolescent Self-Rating Life Events Check List (ASLEC) and Egna Minnen Beträffande Uppfostran (EMBU) were used for screening these two groups. CBCL total scores differed significantly by sex in the Positive group according to the Mann-Whitney tests (Z = -5.40, p < 0.001). Multiple regression analyses showed that the dimensions of punishment (p = 0.014) and other (p = 0.048) in the ASLEC scale can significantly predict CBCL total scores in the Positive group. Sex, age and overprotection from the father were risk factors (p < 0.001) according to binary logistic regression. Life events and parenting styles may have impacts on mental health. Fathers play a very important role in children's growth. Punitive education and fathers' overprotection might be risk factors for children's mental health. It is a large sample (3535) study of Chinese children and adolescents It provides evidence that life events and parenting styles have impacts on mental health and that fathers play a very important role in children's growth. It is conducive to the development of interventions for the mental health of children and adolescents.

Potential risk factors for the development from immune thrombocytopenia to systemic lupus erythematosus: a case-control study in Chinese children.

Immune thrombocytopenia (ITP) patients are at risk developing to systemic lupus erythematosus (SLE) in the future. Our study attempted to explore the potential risk factors for the development from ITP to SLE in Chinese children by statistical analysis. This study was a retrospective case-control study. Patients diagnosed with ITP and developed to SLE after the diagnosis of ITP were defined as the case group. The control group consisted of children with ITP but without developing to SLE was recruited with a ratio of 1:2. Besides univariable analysis, multivariable logistic regression was built to evaluate the potential risk factors. A total of 150 children was included with 50 in the case group and 100 in the control group. Median developing time from ITP to SLE was 34.5 [IQR 12.5, 58.75] months. ANA was found significantly different between the two groups in our study in the univariable analysis but not in the multivariable analysis (OR = 4.50, 95% CI 0.97 to 21.01). Age diagnosed ITP was positively associated with SLE (OR = 1.07 every 5years, 95% CI 1.01 to 1.15) with alert point at 8years old (sensitivity 0.82, specificity 0.60). A lower level of complement was also positively associated with SLE (OR = 8.33, 95% CI 1.62 to 42.91). A minimum 3-year of close follow-up for pediatric ITP patients was recommended to monitor the risk for developing SLE. Older age and hypocomplementemia were potential risk factors for the development from ITP to SLE.

The Chinese minority in Bucharest: A case study of Chinese children raised and cared for by Romanian nannies

Since 1990, many Chinese immigrants have come to Romania. These Chinese persons are full time involved in the profitable wholesale and retail trade activities; they have families and children, cared for by Romanian nannies. The study is focused on the particularities of an intercultural dialogue, unique and recenlty highlighted in the Romanian society: between the Romanian nannies and Chinese children, located in a representative urban area for the Chinese minority. The aim of paper is to analyses how two cultures have interacted for the purpose of child care, focusing on the ways in which the life, experiences, attitudes and opportunities of Chinese children are socially and spatially shaped, influenced and structured by cultural features of the Romanian nannies.

CON: All Patients With Immune-Tolerated Hepatitis B Virus Do Not Need to Be Treated.

http://aasldpubs.onlinelibrary.wiley.com/hub/journal/10.1002/(ISSN)2046-2484/video/15-1-reading-attar a video presentation of this article.

The use of wearable cameras in assessing children's dietary intake and behaviours in China

The use of lifelogging device in dietary assessments can reduce misreporting and underreporting, which are common in the previous studies conventional methods. We performed the first study in Chinese children (primary school Grade 4) that applied the wearable cameras in assisting dietary recall. Children (n = 52) wore the wearable cameras (Narrative Clip 2) for seven consecutive days, during which they completed a 3-day 24-h dietary recall at home. Then children modified their dietary recalls at school by reviewing the photos taken by the wearable camera at school, with the assistance of the investigator, and generated the camera-assisted 24-h dietary recalls. Compared with camera-assisted dietary recalls, 8% (n = 160) and 1% (n = 11) of food items were underreported (i.e. not reported at all) and misreported (i.e. reported in an incorrect amount) by dietary recalls without camera-assistance, respectively. Dietary recalls without camera assistance underestimated daily energy intake by 149 ± 182 kcal/d (8%) in comparison to the camera-assisted dietary recalls. Foods consumed on the snacking occasions (40%) were more likely to be underreported than those consumed at main meals (P < 0.001). Beverages (37%), fruits (30%), snacks and desserts (16%) were foods most likely to be inaccurately reported. Children were satisfied with the wearable cameras, with a median score 5.0 (IQR: 5.0–5.0) for most features. Wearable cameras hold promise for improving accuracy of dietary intake assessment in children, providing rich objective information on dietary behaviours, and received high level of satisfaction and compliance of the users. Our results suggest that the accuracy of dietary recall among Chinse school-aged children could be improved by wearable camera, especially avoiding underreporting in the snacking occasions.

Stress response genes associated with attention deficit hyperactivity disorder: A case-control study in Chinese children

To explore the associations between stress response genes and attention deficit hyperactivity disorder (ADHD) in children, we conducted a case-control study consisting of 406 newly diagnosed ADHD cases and 432 controls in Wuhan, China. We genotyped the candidate genes, nuclear receptor subfamily 3 group C member 1(NR3C1) and solute carrier family 6 member 4(SLC6A4), using the Sequenom MassARRAY technology. After correction by Bonferroni (α' = 0.05/6 = 0.008), the rs6191 SNP was found to be associated with a reduced risk of ADHD in the dominant model (OR = 0.564, 95% CI = 0.389-0.819, P = 0.003) while the rs25531 SNP was associated with an increased risk of ADHD in the multiplicative model (OR = 1.380, 95% CI = 1.111–1.714, P = 0.004). Additionally, both the rs6191 and rs25531 SNPs were significantly associated with the attention deficit factor (P = 0.006, P = 0.003, respectively) but not with the hyperactivity/impulsivity factor in the Swanson, Nolan and Pelham-IV Questionnaire (SNAP-IV) scale. Furthermore, we found that these two SNPs were significantly associated with pure ADHD, and not affected by the comorbidities (P = 0.001, P = 0.007, respectively). Besides, there was an interaction between these two SNPs. This study demonstrated the role of NR3C1 and SLC6A4 polymorphisms in ADHD, yet independent replication of the findings of this study in multi-center and multi-stage studies with large samples is warranted in the future.

A Corpus-Driven Study of Chinese Children’s Multimodal Refusal and Its Implications for Home Education

Multimodal refusal is a common type of multimodal communicative act. Driven by naturally occurred corpus, this paper first classifies the parental acts that usually trigger children’s refusal into three types: positive parenting, negative parenting and non-parenting acts. Then the paper thoroughly analyzes the multimodal representational characteristics of Chinese-speaking children’s refusal and classifies their multimodal refusal acts according to the modal involvement on the one hand and the semantic degree of refusal on the other hand. They are verbal-dominant refusal, nonverbal-dominant refusal and verbal-nonverbal consistent refusal according to modal involvement and complete refusal and partial refusal according to degree of refusal. Finally, the paper summarizes three pieces of suggestions for parents in home education, including emphasizing the multimodal nature of children’s refusal, adjusting parenting acts that may trigger children’s refusal and cultivating children’s ability of multimodal refusal.

RAN/RANBP2 polymorphisms and neuroblastoma risk in Chinese children: a three-center case-control study.

The genetic etiology of sporadic neuroblastoma remains largely obscure. RAN and RANBP2 genes encode Ras-related nuclear protein and Ran-binding protein 2, respectively. These two proteins form Ran-RanBP2 complex that regulate various cellular activities including nuclear transport. Aberrant functions of the two proteins are implicated in carcinogenesis. Given the unknown role of RAN/RANBP2 single nucleotide polymorphisms (SNPs) in neuroblastoma risk, we performed a multi-center case-control study in Chinese children to assess the association of the RAN/RANBP2 SNPs with neuroblastoma risk. We analyzed three potentially functional SNPs in RAN gene (rs56109543 C>T, rs7132224 A>G, rs14035 C>T) and one in RANBP2 (rs2462788 C>T) in 429 cases and 884 controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to access the association between these four polymorphisms and neuroblastoma risk. No single variant was found to statistically significantly associate with neuroblastoma risk. However, individuals with 3 protective genotypes were less likely to develop neuroblastoma, in comparison to non-carriers (adjusted OR=0.33; 95% CI=0.12-0.96; P=0.042), as well as those with 0-2 protective genotypes (adjusted OR=0.33; 95% CI=0.11-0.94; P=0.038). Stratified analysis revealed no significant association for any of the four polymorphisms. Further studies are warranted to validate the weak impact of RAN/RANBP2 SNPs on neuroblastoma risk.

Association of Common Genetic Variants in Pre-microRNAs and Neuroblastoma Susceptibility: A Two-Center Study in Chinese Children

Neuroblastoma is a commonly occurring extracranial pediatric solid tumor without defined etiology. Polymorphisms in pre-miRNAs have been demonstrated to associate with the risk of several cancers. So far, no such polymorphism has been investigated in neuroblastoma. With this in mind, we performed a two-center case-control study to assess the association of genetic variants in pre-miRNAs and neuroblastoma susceptibility in Chinese children, including 393 cases and 812 controls. We found that miR-34b/c rs4938723 T > C polymorphism was significantly associated with decreased neuroblastoma risk (TC versus TT: adjusted odds ratio [OR] = 0.51, 95% confidence interval [CI] = 0.39–0.67; TC/CC versus TT: adjusted OR = 0.62, 95% CI = 0.48–0.79). We also observed the significant association between the miR-218 rs11134527 A > G polymorphism and decreased neuroblastoma risk (AG versus AA: adjusted OR = 0.73, 95% CI = 0.56–0.96). Stratified analysis further demonstrated that the protective effect of the rs4938723 T > C polymorphism remained prominent in the subgroups, regardless of age, gender, and clinical stages. In term of sites of origin, this polymorphism significantly reduced the risk of tumors originating from the adrenal gland. We further validated the significant results using false-positive report probability analyses. Overall, the miR-34b/c rs4938723 T > C and miR-218 rs11134527 A > G polymorphisms displayed a protective role from neuroblastoma. These findings need further validation.

The Associations between Perceived Parenting Styles, Empathy, and Altruistic Choices in Economic Games: A Study of Chinese Children.

Parenting styles are critical for fostering children’s empathy and prosociality. Yet these relations haven’t been well established for Chinese children, and the underlying mechanisms were seldom explored. Drawing upon parental acceptance-rejection theory and empathy-altruism hypothesis, the objective of this study was to investigate the relationships between perceived parenting styles and altruistic behavior of children, and the intervening role of children’s empathy and the moderating role of in-group and out-group conditions. What is novel about this study is that it contains both survey data and experimental data. Four hundred and ninety-four children (Mage = 8.92 years) completed four simple binary-choice dictator games which are widely used in the study of other-regarding preferences (concerns for the interests of others). These children also reported their perceived parenting styles. And children’s empathy was reported by their mothers. Each child’s altruism score, which was used in the subsequent analyses, was derived from the altruistic choices in these games. Mediation analyses indicated that, when age and gender were controlled for, maternal and paternal emotional warmth were positively associated with children’s altruism via children’s empathy, while maternal and paternal rejection were negatively associated with children’s altruism via children’s empathy. Multi-group analyses showed that the influences of perceived parenting styles on children’s altruistic behavior via children’s empathy were consistent for in-group and out-group conditions. These findings suggest that enhancing parental emotional warmth and reducing parental rejection may foster children’s empathy, which in turn promote children’s altruism. Limitations and future directions of this study were also discussed.

Openness to Experience as a Moderator of the Relationship between Intelligence and Creative Thinking: A Study of Chinese Children in Urban and Rural Areas.

Using testing and questionnaire methods, this study investigated the relationships among openness to experience, intelligence and creative thinking. This study focused on the moderating effects of openness to experience on the relationship between intelligence and creative thinking in a sample of 831 primary school students in China. The findings showed significant positive relationships among openness to experience, intelligence and creative thinking. In relation to the focus of this study, openness to experience moderated the relationship between intelligence and creative thinking. However, the correlation between openness to experience and creative thinking was stronger for urban children than for rural children, and the moderating effect existed only in urban settings.

Maternal gestational diabetes mellitus and overweight and obesity in offspring: a study in Chinese children.

The purpose of this study was to investigate the effects of maternal gestational diabetes mellitus (GDM) and breast feeding on childhood overweight and obesity in a mainland Chinese population. The incidence of and factors associated with overweight and obesity were compared between children of mothers with (n=1068) and without (n=1756) GDM. The independent roles of the associated factors were examined by multiple logistic regression analysis. The incidence of overweight was higher (16.6 v. 12.6%, P=0.002) in the GDM group, but that of obesity was not different (10.7 v. 12.0%, P=0.315). At age 1-2 and 2-5 years, no difference in overweight (11.0 v. 12.0%, P=0.917, and 15.7 v. 14.6%, P=0.693, respectively) was found, while obesity (8.0 v. 13.6%, P=0.019, and 8.4 v. 13.4%, P=0.014, respectively) was less frequent in the GDM offspring. At age 5-10 years, increased overweight (22.2 v. 12.1%, P<0.001) and obesity (15.9 v. 9.0%, P=0.001) were found in the GDM group, which was associated with maternal obesity, being born large-for-gestational age, male gender and formula feeding. After adjusting for confounding factors, GDM remained an independent determinant of offspring overweight and obesity (aOR 2.28, 95% CI 1.61-3.22), suggesting that the effects of GDM were independent of breast feeding, as well as of maternal obesity and birth size.

Effect of undercorrection on myopia progression in 12-year-old children.

To prospectively observe the effects of undercorrection of myopia on myopia progression and axial elongation in a population of 12-year-old Chinese children. A total of 2,267 children in the Anyang Childhood Eye Study were examined at baseline, and 1,769 were followed for 1 year. Ocular examinations included cycloplegic autorefraction, axial length, visual acuity, vertometry, and accommodative lag. Questionnaires were completed by children and parents. Undercorrection of myopia was determined at baseline if presenting visual acuity could be improved by at least 2 lines with subjective refraction. Of 253 myopic children with spectacles and available information, 120 (47.4 %) were undercorrected (-4.63D to -0.50D) and 133 (52.6 %) were fully corrected. In a multivariate model adjusting for age, gender, number of myopic parents, time spent on near work and outdoor activities per day, usage and time for wearing spectacles per day, children with undercorrection had significantly more baseline myopia (P < 0.01) and longer axial length (P = 0.03) than children with full correction. However, there were no significant differences in myopia progression (P = 0.46) and axial elongation (P = 0.96) at 1 year between the two groups of children. The regression analysis showed that myopia progression significantly decreased with increasing amount of undercorrection (r (2) = 0.02, P = 0.02) in all children. Accommodative lag significantly decreased with increasing amounts of undercorrection (P < 0.01). Based on this 1-year study in Chinese children, undercorrection or full correction of myopia by wearing spectacles did not show any differences in myopia progression or axial elongation.

Treatment of Acute Myeloid Leukemia with the NOPHO-AML 2004 Study in Chinese Children: A Single Center Study

Objectives: The objective of the present study was to investigate the therapeutic efficacy and feasibility of NOPHO-AML 2004 study in the treatment of acute myeloid leukemia (AML; excluding acute promyelocytic leukemia) in Chinese children.Methods: Thirty-one children with novo AML treated with the NOPHO-AML 2004 study were recruited from Jan. 2010 to Dec. 2013, and the clinical data were retrospectively analyzed. Among 31 AML children, their age were from 2-14 years old (median age 8 years old). There were 12,15 and 4 children classified in low risk group, intermediate risk group and high risk group by cytogenetic risk classification respectively. Eight children received concomitant hematopoietic stem cell transplantation. Kaplan Meier method with Log-Rank testing was employed for survival analysis.Results: Follow-up was for a median 24 months (range: 5–50 months). The complete remission rate was 83.8%. The predicted 3-year leukemia free survival (LFS) rate was 53.8%. The LFS rate of low, intermediate and high risk group were 55.6%, 52.5% and 50.0% respectively. There was no significance in risk groups. The LFS rate of chemotherapy and chemotherapy concomitant HSCT were 42.7% and 87.5%, P<0.05. There were 2 cases of treatment related mortality including one case of sepsis and one case of ARDS.Conclusions: NOPHO-AML 2004 study is clinically efficacious for the treatment of AML in Chinese children. HSCT treatment had better outcome than only chemotherapy in childhood with non low risk AML in CR1 phase. DisclosuresNo relevant conflicts of interest to declare.

Air pollution associated hypertension and increased blood pressure may be reduced by breastfeeding in Chinese children: The Seven Northeastern Cities Chinese Children's Study

BackgroundLittle is known about the association between air pollution and hypertension among children, and no studies report whether breastfeeding modifies this association in children. MethodsNine thousand three hundred fifty-four Chinese children, ages 5–17 years old, from 24 elementary schools and 24 middle schools in the Seven Northeastern Cities during 2012–2013 were evaluated. The weight, height, and BP were measured. Four-year average concentrations of particles with an aerodynamic diameter of ≤10μm (PM10), sulfur dioxide (SO2), nitrogen dioxides (NO2), ozone (O3), and carbon monoxide (CO) were calculated from monitoring stations. Two-level regression analysis was used to examine the effects, controlling for covariates. ResultsThe results showed that associations existed between hypertension and pollutants. The odds ratios for hypertension ranged from 1.12 per 46.3μg/m3 increase for O3 (95% confidence interval [CI], 1.10–1.13) to 1.68 per 30.6μg/m3 increase for PM10 (95% CI, 1.53–1.86). The increases in mean diastolic BP ranged from 0.58mm Hg per 46.3μg/m3 increase for O3 (95% CI, 0.52–0.63mm Hg) to 2.89mm Hg per 563.4μg/m3 increase for CO (95% CI: 2.53–3.24mm Hg). The increase in systolic BP ranged from 0.50mm Hg per 46.3μg/m3 increase for O3 (95% CI: 0.43–0.57mm Hg) to 2.10mm Hg per 30.6μg/m3 increase for PM10 (95% CI, 1.73–2.47mm Hg). Compared with children who had been breastfed, non-breastfed children exhibited consistently stronger effects. ConclusionStudy findings indicate that high levels of PM10, SO2, NO2, O3, and CO are associated with increased arterial BP and hypertension among the children. Breastfeeding may reduce the risk.

Developmental trauma and its correlates: a study of Chinese children with repeated familial physical and sexual abuse in Hong Kong.

The present study examined the relevance of the developmental trauma disorder (DTD) framework (van der Kolk, ) in Hong Kong Chinese children with repeated familial physical and/or sexual abuse. Self-reports of (a) key dimensions of DTD including emotion regulation, attribution and perceptions in self and relationships, belief in future victimization, behavioral difficulties, and self-esteem; and (b) attachment styles and posttraumatic stress disorder (PTSD) reactions were obtained from children aged 9-15 years in clinical and school settings. Children were categorized into an abused trauma group (n = 82), a nonabused trauma group (n = 83), and a no-trauma control group (n = 201). The findings indicated that the DTD framework was applicable to abused children who showed a lower level of attachment security (Cohen's d from 0.50-0.61) and a higher level of PTSD reactions (Cohen's d = 0.71) than the comparison groups. After adding attachment security and emotion dysregulation to the model, there were no longer significant group differences in most of the variables.

Clinical characteristics and chromosome 11p15 imprinting analysis of Silver-Russell syndrome - a Chinese experience.

Silver-Russell syndrome (SRS) is an imprinting defect disease. This is the first study of Chinese children with SRS caused by chromosome 11p15 imprinting defects. Twenty-five SRS cases, diagnosed in Beijing Children's Hospital from 2006 to 2012, were studied retrospectively to detect chromosome 11p15 imprinting defects. Over 80% of the children had (i) small for gestational age and postnatal growth retardation (mean height standard deviation score [HT SDS] was -3.56), (ii) mean body mass index (BMI) SDS was -2.10, and (iii) skeletal malformation. Chromosome 11p15 imprinting defects were examined in 16 of the 25 patients. Six had hypomethylation in chromosome 11p15 imprinting control region 1 (ICR1) of the paternal allele; one had hypomethylation in chromosome 11p15 ICR1 and hypermethylation in imprinting control region 2 (ICR2). Another patient had a duplicated maternal chromosome 11p15 fragment. Six patients had been treated with for 3-24 months. Growth rates ranged from 4 to 10.8 cm/year. This study demonstrated that Chinese children with SRS had more growth retardation than bone retardation, severely low levels of BMI, triangular faces, and limb asymmetry. Chromosome 11p15 imprinting defects contributed to 50% of these cases, and ICR1 hypomethylation was associated with asymmetry.