Genomic imprinting refers to the phenomenon of differential expression of two alleles due to their different parental origins. Genes that produce genomic imprinting are usually called imprinted genes. The genetic effect caused by the presence of imprinted genes is called parent-of-origin effect. Parent-of-origin effect and genomic imprinting play important roles in the pathophysiological mechanism and occurrence and development of cardio-metabolic diseases. In-depth exploration of the law and potential roles of imprinted genes and parent-of-origin effects will help to better understand the mechanism of cardio-metabolic diseases, and also provide important theoretical basis for the precise treatment of diseases related to imprinted genes.

Objective:To explore the spousal correlations of total cholesterol(TC),total triglyceride(TG),low-density lipoprotein cholesterol(LDL-C),and high-density lipoprotein cholesterol(HDL-C),and to investigate the reasons behind these spousal correlations.Methods:Participants and data were from the baseline survey of family-based cohort studies in Fangshan,Beijing and Tulou,Fujian.The ori-gin of spousal correlations were explored from perspectives of convergence,assortative mating,social ho-mogamy.Pearson's correlation and generalized linear models(GLM)were used to estimate the spousal correlation.Convergence was assessed by Pearson's correlation between the phenotypic differences be-tween couples and the duration of marriage,with GLM used for further validation.Pearson's correlation of genetic risk scores(GRS)and couple-specific Mendelian randomization(MR)were calculated to assess the genetic correlation and possible causal relationships between spouses.Two-independent-sample t-tests were used to compare GRS consistency across subgroups divided by education attainment,couple-specific MR and Q statistics used to test assortative mating in subgroups and intergroup differences.Results:In the study,342 couples(287 couples from Fangshan and 55 couples from Fujian)were included,with the average age of(64.91±8.76)years.Spousal correlations of TC,TG,HDL-C,and LDL-C showed statistically significant associations both before and after adjusting for covariates,with effect sizes of 0.229(95％CI:0.125-0.327),0.257(95％CI:0.155-0.354),0.179(95％CI:0.074-0.280),and 0.181(95％CI:0.076-0.282).For convergence,for each additional year of marriage,ΔTC increased by 0.016 mmol/L(95％CI:0.001-0.033 mmol/L),and ΔLDL-C increased by 0.017 mmol/L(95％CI:0.002-0.031 mmol/L).For assortative mating,GRS correlations and results of couple specific MR didn't show any statistical significance.For social homogamy,no differences in GRS or assortative mating were found between subgroups stratified by education attainment.Conclusion:The blood lipid in participants exhibit spousal phenotypic correlations,however,no effects of convergence,assortative mating or social homogamy were observed.More independent studies with larger sample sizes are warranted to further validate these findings in the future.

Genomic imprinting refers to the phenomenon of differential expression of two alleles due to their different parental origins. Genes that produce genomic imprinting are usually called imprinted genes. The genetic effect caused by the presence of imprinted genes is called parent-of-origin effect. Parent-of-origin effect and genomic imprinting play important roles in the pathophysiological mechanism and occurrence and development of cardio-metabolic diseases. In-depth exploration of the law and potential roles of imprinted genes and parent-of-origin effects will help to better understand the mechanism of cardio-metabolic diseases, and also provide important theoretical basis for the precise treatment of diseases related to imprinted genes.

Objective:To explore the spousal correlations of total cholesterol(TC),total triglyceride(TG),low-density lipoprotein cholesterol(LDL-C),and high-density lipoprotein cholesterol(HDL-C),and to investigate the reasons behind these spousal correlations.Methods:Participants and data were from the baseline survey of family-based cohort studies in Fangshan,Beijing and Tulou,Fujian.The ori-gin of spousal correlations were explored from perspectives of convergence,assortative mating,social ho-mogamy.Pearson's correlation and generalized linear models(GLM)were used to estimate the spousal correlation.Convergence was assessed by Pearson's correlation between the phenotypic differences be-tween couples and the duration of marriage,with GLM used for further validation.Pearson's correlation of genetic risk scores(GRS)and couple-specific Mendelian randomization(MR)were calculated to assess the genetic correlation and possible causal relationships between spouses.Two-independent-sample t-tests were used to compare GRS consistency across subgroups divided by education attainment,couple-specific MR and Q statistics used to test assortative mating in subgroups and intergroup differences.Results:In the study,342 couples(287 couples from Fangshan and 55 couples from Fujian)were included,with the average age of(64.91±8.76)years.Spousal correlations of TC,TG,HDL-C,and LDL-C showed statistically significant associations both before and after adjusting for covariates,with effect sizes of 0.229(95％CI:0.125-0.327),0.257(95％CI:0.155-0.354),0.179(95％CI:0.074-0.280),and 0.181(95％CI:0.076-0.282).For convergence,for each additional year of marriage,ΔTC increased by 0.016 mmol/L(95％CI:0.001-0.033 mmol/L),and ΔLDL-C increased by 0.017 mmol/L(95％CI:0.002-0.031 mmol/L).For assortative mating,GRS correlations and results of couple specific MR didn't show any statistical significance.For social homogamy,no differences in GRS or assortative mating were found between subgroups stratified by education attainment.Conclusion:The blood lipid in participants exhibit spousal phenotypic correlations,however,no effects of convergence,assortative mating or social homogamy were observed.More independent studies with larger sample sizes are warranted to further validate these findings in the future.

Objective:To explore the effects of short-term particulate matter(PM)exposure and the melatonin receptor 1B(MTNR1B)gene on triglyceride-glucose(TyG)index utilizing data from Fang-shan Family-based Ischemic Stroke Study in China(FISSIC).Methods:Probands and their relatives from 9 rural areas in Fangshan District,Beijing,were included in the study.PM data were obtained from fixed monitoring stations of the National Air Pollution Monitoring System.TyG index was calculated by fasting triglyceride and glucose concentrations.The associations of short-term PM exposure and rs10830963 polymorphism of the MTNR1B gene with the TyG index were assessed using mixed linear models,in which covariates such as age,sex,and lifestyles were adjusted for.Gene-environment inter-action analysis was furtherly performed using the maximum likelihood methods to explore the potential effect modifier role of rs10830963 polymorphism in the association of PM with TyG index.Results:A total of 4 395 participants from 2 084 families were included in the study,and the mean age of the study participants was(58.98±8.68)years,with 53.90％females.The results of association analyses showed that for every 10 μg/m3 increase in PM2.5 concentration,TyG index increased by 0.017(95％CI:0.007-0.027),while for per 10 μg/m3 increment in PM1o,TyG index increased by 0.010(95％CI:0.003-0.017).And the associations all had lagged effects.In addition,there was a positive association between the rs10830963 polymorphism and the TyG index.For per increase in risk allele G,TyG index was elevated by 0.040(95％CI:0.004-0.076).The TyG index was 0.079(95％CI:0.005-0.152)higher in carriers of the GG genotype compared with carriers of the CC genotype.The inter-action of rs10830963 polymorphism with PM exposure had not been found to be statistically significant in the present study.Conclusion:Short-term exposure to PM2.5 and PM10 were associated with higher TyG index.The G allele of rs10830963 polymorphism in the MTNR1B gene was associated with the elevated TyG index.

Objective:To explore the association between polymorphisms of transforming growth factor-β(TGF-β)signaling pathway and non-syndromic cleft lip with or without cleft palate(NSCL/P)among Asian populations,while considering gene-gene interaction and gene-environment interaction.Methods:A total of 1 038 Asian NSCL/P case-parent trios were ascertained from an international consortium,which conducted a genome-wide association study using a case-parent trio design to investigate the genes affec-ting risk to NSCL/P.After stringent quality control measures,343 single nucleotide polymorphism(SNP)spanning across 10 pivotal genes in the TGF-β signaling pathway were selected from the original genome-wide association study(GWAS)dataset for further analysis.The transmission disequilibrium test(TDT)was used to test for SNP effects.The conditional Logistic regression models were used to test for gene-gene interaction and gene-environment interaction.Environmental factors collected for the study in-cluded smoking during pregnancy,passive smoking during pregnancy,alcohol intake during pregnancy,and vitamin use during pregnancy.Due to the low rates of exposure to smoking during pregnancy and al-cohol consumption during pregnancy(＜3％),only the interaction between maternal smoking during pregnancy and multivitamin supplementation during pregnancy was analyzed.The threshold for statistical significance was rigorously set at P=1.46 × 10-4,applying Bonferroni correction to account for multiple testing.Results:A total of 23 SNPs in 4 genes yielded nominal association with NSCL/P(P＜0.05),but none of these associations was statistically significant after Bonferroni's multiple test correction.How-ever,there were 6 pairs of SNPs rs4939874(SMAD2)and rs1864615(TGFBR2),rs2796813(TGFB2)and rs2132298(TGFBR2),rs4147358(SMAD3)and rs1346907(TGFBR2),rs4939874(SMAD2)and rs1019855(TGFBR2),rs4939874(SMAD2)and rs12490466(TGFBR2),rs2009112(TGFB2)and rs4075748(TGFBR2)showed statistically significant SNP-SNP interaction(P＜1.46 × 10-4).In contrast,the analysis of gene-environment interactions did not yield any significant results after being cor-rected by multiple testing.Conclusion:The comprehensive evaluation of SNP associations and interac-tions within the TGF-β signaling pathway did not yield any direct associations with NSCL/P risk in Asian populations.However,the significant gene-gene interactions identified suggest that the genetic architec-ture influencing NSCL/P risk may involve interactions between genes within the TGF-β signaling path-way.These findings underscore the necessity for further investigations to unravel these results and further explore the underlying biological mechanisms.

Objective:To understand the major cognition, major choice motivation and the relationship between the two of medical students, and provide references and suggestions for the selection of talents in various majors of medical schools and the effective development of enrollment work.Methods:This study selected undergraduates of Batch 2019 from Peking University Health Science Center as the survey objects, conducted a questionnaire survey on their major cognition, major choice motivation and influencing factors, and used principal component analysis and Spearman rank correlation analysis.Results:The study found that the major cognition scores of 640 undergraduates of Batch 2019 from Peking University Health Science Center were clinical medicine (3.24±0.89) > stomatology (2.89±1.00) > basic medicine (2.66±1.02) > pharmacy (2.54±0.97) > preventive medicine (2.29±0.93) > nursing medicine (2.21±0.99) > medical laboratory (1.98±0.95) > medical English (1.95±0.93). Six major motivation factors for professional choice were school and professional strength, professional learning and job prospects, own factors, Peking University sentiments and the influence of others, medical factors, school policies, and the contribution rates were 34.60%, 12.97%, 7.42%, 6.00%, 5.59% and 5.37%, respectively. Major cognition scores and major choice motivation factors were positively correlated with each other to some extent.Conclusions:At present, students' major cognition level of medical majors still has a large room for improvement, and the motivational factors of major choice are more complicated, among which "the school and professional strength" and "the prospects of study and work" are important factors. Medical schools should focus on strengthening major publicity, improving students' major cognition, attracting aspiring students to apply for medical majors from many aspects, and improving the training quality of medical professionals.