Progress in research of risk factors of iron deficiency and intervention in blood donors / 中华流行病学杂志

Long-term repeated regular blood donation may result in the loss and deficiency of iron. Epidemiological studies have indicated that blood donation frequency, demographical characteristics, and genetic factors are associated with iron deficiency. Our review summarizes the progress in research of etiology of iron deficiency in blood donors and intervention measures to provide evidence for the health management of non-remunerated blood donors in China.

Association study between haplotypes of WNT signaling pathway genes and nonsyndromic oral clefts among Chinese Han populations / 北京大学学报(医学版)

OBJECTIVE@#To explore whether WNT signaling pathway genes were associated with non-syndromic oral clefts (NSOC) based on haplotypes analyses among 1 008 Chinese NSOC case-parent trios.@*METHODS@#The genome-wide association study (GWAS) data of 806 Chinese non-syndromic cleft lip with or without cleft palate (NSCL/P) trios and 202 Chinese non-syndromic cleft palate (NSCP) case-parent trios were drawn from the International Consortium to Identify Genes and Interactions Controlling Oral Clefts (ICOCs) study GWAS data set, whose Chinese study population were recruited from four provinces in China, namely Taiwan, Shandong, Hubei, and Sichuan provinces. The process of DNA genotyping was conducted by the Center for Inherited Disease Research in the Johns Hopkins University, using Illumina Human610-Quad v.1_B Bead Chip. The method of sliding windows was used to determine the haplotypes for analyses, including 2 SNPs haplotypes and 3 SNPs haplotypes. Haplotypes with a frequency lower than 1% were excluded for further analyses. To further assess the association between haplotypes and NSOC risks, and the transmission disequilibrium test (TDT) was performed. The Bonferroni method was adopted to correct multiple tests in the study, with which the threshold of statistical significance level was set as P < 0.05 divided by the number of tests, e.g P < 3.47×10-4 in the current stu-dy. All the statistical analyses were performed by using plink (v1.07).@*RESULTS@#After quality control, a total of 144 single nucleotide polymorphisms (SNPs) mapped in seven genes in WNT signaling pathway were included for the analyses among the 806 Chinese NSCL/P trios and 202 Chinese NSCP trios. A total of 1 042 haplotypes with frequency higher than 1% were included for NSCL/P analyses and another 1 057 haplotypes with frequency higher than 1% were included for NSCP analyses. Results from the TDT analyses showed that a total of 69 haplotypes were nominally associated with the NSCL/P risk among Chinese (P < 0.05). Another 34 haplotypes showed nominal significant association with the NSCP risk among Chinese (P < 0.05). However, none of these haplotypes reached pre-defined statistical significance level after Bonferroni correction (P>3.47×10-4).@*CONCLUSION@#This study failed to observe any statistically significant associations between haplotypes of seven WNT signaling pathway genes and the risk of NSOC among Chinese. Further studies are warranted to replicate the findings here.

Evaluating the effect of WNT pathway genes considering interactions on the risk of non-syndromic oral clefts among Chinese populations / 北京大学学报(医学版)

OBJECTIVE@#In this study, we used genome-wide association study (GWAS) data to explore whether WNT pathway genes were associated with non-syndromic oral clefts (NSOC) considering gene-gene interaction and gene-environment interaction.@*METHODS@#We conducted the analysis using 806 non-syndromic cleft lip with or without cleft palate (NSCL/P) case-parent trios and 202 non-syndromic cleft palate (NSCP) case-parent trios among Chinese populations selected from an international consortium established for a GWAS of non-syndromic oral clefts. Genotype data and maternal environmental exposures were collected through DNA samples and questionnaires. Conditional Logistic regression models were adopted to explore gene-gene interaction and gene-environment in teraction using trio package in R software. The threshold of significance level was set as 3.47×10-4 using Bonferroni correction.@*RESULTS@#A total of 144 single nucleotide polymorphisms (SNPs) in seven genes passed the quality control process in NSCL/P trios and NSCP trios, respectively. Totally six pairs of SNPs interactions showed statistically significant SNP-SNP interaction (P < 3.47×10-4) after Bonferroni correction, which were rs7618735 (WNT5A) and rs10848543 (WNT5B), rs631948 (WNT11) and rs556874 (WNT5A), and rs631948 (WNT11) and rs472631 (WNT5A) among NSCL/P trios; rs589149 (WNT11) and rs4765834 (WNT5B), rs1402704 (WNT11) and rs358792 (WNT5A), and rs1402704 (WNT11) and rs358793 (WNT5A) among NSCP trios, respectively. In addition, no significant result was found for gene-environment interaction analysis in both of the NSCL/P trios and NSCP trios.@*CONCLUSION@#Though this study failed to detect significant association based on gene-environment interactions of seven WNT pathway genes and the risk of NSOC, WNT pathway genes may influence the risk of NSOC through potential gene-gene interaction.

Exploring parent-of-origin effects for non-syndromic cleft lip with or without cleft palate on PTCH1, PTCH2, SHH, SMO genes in Chinese case-parent trios / 北京大学学报(医学版)

OBJECTIVE@#Non-syndromic cleft lip with or without cleft palate (NSCL/P) is a common birth defect, affecting 1.4 per 1 000 live births, and multiple genetic and environmental risk factors influencing its risk. All the known genetic risk factors accounted for a small proportion of the heritability. Several authors have suggested parent-of-origin effects (PoO) may play an important role in the etiology of this complex and heterogeneous malformation. To clarify the genetic association between PTCH1, PTCH2, SHH and SMO in hedgehog (HH) pathway and NSCL/P, as well as testing for potential PoO effects in Chinese case-parent trios.@*METHODS@#We tested for transmission disequilibrium tests (TDT) and PoO effects using 83 common single nucleotide polymorphic (SNP) markers of HH pathway genes from 806 NSCL/P case-parent trios. These trios were drawn from an international consortium established for a genome-wide association studies (GWAS) of non-syndromic oral clefts of multiple ethnicities. DNA samples were collected from each trio. Single marker and haplotype based analysis were performed both in TDT tests and PoO effects. SNPs were excluded if they (ⅰ) had a call rate of < 95%, (ⅱ) had a minor allele frequency (MAF) of < 0.05, (ⅲ) had Mendelian errors over all trios of >5%, (ⅳ) had a genotype distribution in the parents that deviated from the Hardy-Weinberg equilibrium (HWE) (<i>P</i> < 0.000 1). The process was done using Plink (version 1.07, <a href="http://pngu.mgh.harvard.edu/~purcell/plink/data.shtml" target="_blank">http://pngu.mgh.harvard.edu/~purcell/plink/data.shtml</a>). TDT test was performed in Plink v1.07. A log-linear model was used to explore PoO effects using Haplin v6.2.1 as implemented in R package v3.4.2. Significance level was assessed using the Bonferroni correction.@*RESULTS@#A total of 18 SNPs were dropped due to low MAF, thus leaving 65 SNPs available for the analysis. Thus the Bonferroni threshold was 7.7×10-4 (0.05/65). Nominal significant association with NSCL/P was found at a SNP (rs4448343 in PTCH1, P=0.023) and six haplotypes (rs10512249-rs4448343, rs1461208-rs7786445, rs10512249-rs4448343, rs16909865-rs10512249-rs4448343, rs1461208-rs7786445-rs12698335, and rs288756-rs288758-rs1151790, P < 0.05). A total of six haplotypes (rs288765-rs1233563, rs12537550-rs11765352, rs872723-rs288765-rs1233563, rs288765-rs1233563-rs288756, rs6459952-rs12537550-rs11765352, and rs12537550-rs11765352-rs6971211) showed PoO effect (P < 0.05). None of the results remained significant after the Bonferroni correction (P>7.7×10-4).@*CONCLUSION@#Neither significant association between SNPs within HH pathway and the risk of NSCL/P nor PoO effects was seen in this study.

Bivariate heritability estimation of resting heart rate and common chronic disease based on extended pedigrees / 北京大学学报(医学版)

OBJECTIVE@#To estimate the univariate heritability of resting heart rate and common chronic disease such as hypertension, diabetes, and dyslipidemia based on extended pedigrees in Fujian Tulou area and to explore bivariate heritability to test for the genetic correlation between resting heart rate and other relative phenotypes.@*METHODS@#The study was conducted in Tulou area of Nanjing County, Fujian Province from August 2015 to December 2017. The participants were residents with Zhang surname and their relatives from Taxia Village, Qujiang Village, and Nanou Village or residents with Chen surname and their relatives from Caoban Village, Tumei Village, and Beiling Village. The baseline survey recruited 1 563 family members from 452 extended pedigrees. The pedigree reconstruction was based on the family information registration and the genealogy booklet. Univariate and bivariate heritability was estimated using variance component models for continuous variables, and susceptibility-threshold model for binary variables.@*RESULTS@#The pedigree reconstruction identified 1 seven-generation pedigree, 2 five-generation pedigrees, 23 four-generation pedigrees, 186 three-generation pedigrees, and 240 two-generation pedigrees. The mean age of the participants was 57.2 years and the males accounted for 39.4%. The prevalence of hypertension, diabetes, dyslipidemia in this population was 49.2%, 10.0%, and 45.2%, respectively. The univariate heritability estimation of resting heart rate, hypertension, and dyslipidemia was 0.263 (95%CI: 0.120－0.407), 0.404 (95%CI: 0.135－0.673), and 0.799 (95%CI: 0.590－1), respectively. The heritability of systolic blood pressure, diastolic blood pressure, fasting glucose, total cholesterol, triglyceride, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol was 0.379, 0.306, 0.393, 0.452, 0.568, 0.852, and 0.387, respectively. In bivariate analysis, there were phenotypic correlations between resting heart rate with hypertension, diabetes, diastolic blood pressure, fasting glucose, and triglyceride. After taking resting heart rate into account, there were strong genetic correlations between resting heart rate with fasting glucose (genetic correlation 0.485, 95%CI: 0.120－1, P<0.05) and diabetes (genetic correlation 0.795, 95%CI: 0.181－0.788, P<0.05).@*CONCLUSION@#Resting heart rate was a heritable trait and correlated with several common chronic diseases and related traits. There was strong genetic correlation between resting heart rate with fasting glucose and diabetes, suggesting that they may share common genetic risk factors.

Exploring the association between SPRY gene family and non-syndromic oral clefts among Chinese populations using data of a next-generation sequencing study / 北京大学学报(医学版)

OBJECTIVE@#To explore the association between SPRY gene family and the risk of non-syndromic oral clefts among Chinese populations, in respect of single nucleotide polymorphisms (SNPs) association and parent-of-origin effects.@*METHODS@#Based on case-parent design, this study used the data of SPRY gene family in a next generation sequencing study of 183 non-syndromic cleft lip with or without cleft palate (NSCL/P) case-parent trios (549 participants) recruited from 2016 to 2018, to analyze the effects of SNP association and parent-of-origin. The sequencing study adopted a two-stage design. In the first stage, whole exome sequencing was conducted among 24 NSCL/P trios with family history to explore potential signals. Then in the second stage, another 159 NSCL/P trios were used as validation samples to verify the signals found in the first stage. The data of general information, disease features and parental environmental exposures for participants were collected through questionnaires. Blood samples were collected from each participant for DNA extraction and sequencing. Transmission disequilibrium tests (TDT) were conducted to test for the association between SNPs and NSCL/P, while Z score tests were applied to analyze parent-of-origin effects. The analyses were performed using Plink (v1.07). TRIO package in R (v3.5.1). Besides, famSKAT analyses were conducted in the first stage to combine the effect of SNPs located on the same gene, using famSKAT package in R(V3.5.1). Bonferroni method was adopted to correct multiple tests in the second stage.@*RESULTS@#Twenty-two SNPs in SPRY gene family were included for analyses after the quality control process in the first stage. Based on the variants annotation, functional prediction and statistical analysis, rs1298215244 (SPRY1) and rs504122 (SPRY2) were included in the second verification stage. TDTs in the verification stage revealed that rs1298215244: T>C, rs504122: G>C and rs504122: G>T were associated with the risk of NSCL/P after Bonferroni corrections, where rs504122: G>T was a rare variation. Although the test for parent-of-origin effect of rs1298215244: T>C reached nominal significance level, no SNP showed significant association with NSCL/P through parent-of-origin effect after Bonferroni corrections.@*CONCLUSION@#This study found that SNPs (including both common and rare variants) among the SPRY gene family were associated with the risk of NSCL/P among Chinese populations. This study failed to detect parent-of-origin effects among the SPRY gene family.