Effects of interactions between environmental factors and KIF1B genetic variants on the risk of hepatocellular carcinoma in a Chinese cohort

AIM: To examine the effect of the potential interaction between KIF1 B variants(rs17401966 and rs3748578) and environmental factors on the risk of hepatocellular carcinoma(HCC) in a high-risk region in China.METHODS: Three hundred and six patients with HCC and 306 hospital-based control participants residing in the Shunde region of Guangdong Province, China were enrolled. Clinical characteristics were collected by reviewing the complete medical histories from the patient archives, and epidemiological data were collected using a questionnaire and clinical examination. Two single nucleotide polymorphisms(SNPs) of KIF1B(rs17401966 and rs3748578) were chosen for the current study. All subjects were genotypedusing a Taq Man real-time polymerase chain reaction. Multiplicative and additive logistic regression models were used to evaluate various gene-environment interactions.RESULTS: Smoking, frequent consumption of raw freshwater fish, hepatitis B virus(HBV) infection, and a family history of HCC were important risk factors for HCC in this population. Chronic infection with HBV was the most important environmental risk factor for HCC [odds ratio(OR) = 12.02; 95% confidence interval(95%CI): 6.02-24.00]. No significant association was found between the KIF1 B variants alone and the risk of HCC. Nevertheless, a significant additive effect modification was observed between rs17401966 and alcohol consumption(P for additive interaction = 0.0382). Compared with non-drinkers carrying either the AG or GG genotype of rs17401966, individuals classified as alcohol consumers with the AA genotype of rs17401966 had a significantly increased risk of HCC(OR = 2.36; 95%CI: 1.49-3.74).CONCLUSION: The gene-environment interaction between the KIF1 B rs17401966 variant and alcohol consumption may contribute to the development of HCC in Chinese individuals.

Effects of genetic and environmental factors and gene-environment interaction on expression variations of genes related to stroke in rat brain

To determine if genetic and environmental (dietary) factors and gene-environment interaction impact on the expression variation of genes related to stroke, we conducted microarray experiments using two homozygous rat strains SHRSR and SHRSP fed with high and low dietary salt levels. We obtained expression data of 8,779 genes and performed the ranking analysis of microarray data. The results show that the genetic difference for stroke in rat brain has a strong effect on expression variations of genes. At false discovery rate (FDR) ≤ 5%, 534 genes were found to be differentially expressed between the genotypes resistant and prone to stroke, among which 304 genes were up-regulated in the resistant genotype and down-regulated in the prone genotype and 230 were down-regulated in the former and up-regulated in the latter. In addition, 365 were functional genes for transcription and translation, receptors (in particular, neurotransmitter receptor), channels of ions, transportation, metabolism and enzymes, and functional and structural proteins. Some of these genes are pivotal genes that cause stroke. However, dietary salt levels and GE interaction do not strongly impact on the expression variations of these genes detected on arrays.

Interaction and Relationship Between Angiotensin ConvertingEnzyme Gene and Environmental Factors Predisposing toEssential Hypertension in MongolianPopulation of China

Objective To investigate the association of specific functional gene ACE (I/D) variants of the renin-angiotensin system with essential hypertension (EH) and interaction between ACE (I/D) gene and risk factors for EH in a genetically homogenous Mongolia rural population of China. Methods Individuals (n=1099) were recruited from general population of Kezuohouqi Banner in Inner Mongolian Autonomous Region. Results The association was found between ACE genotype DD plus ID and EH, with an interaction between ACE genotype DD plus ID and cigarette smoking in an additive model. Cigarette smoking index and ACE gene showed a low exposure-gene (LEG) effect on EH, with interaction indices from 7.10 to 1.16. Interaction between ACE genotype DD plus ID and alcohol drinking on EH appeared an additive model. Alcohol drinking index and ACE gene showed a low exposure-gene (LEG) effect on EH, with interaction indices from 1.66 to 1.09. BMI and ACE gene showed a low exposure-gene (LEG) effect on EH, with interaction indices from 6.15 to 2.49. Interactions between ACE genotype and WHR on EH showed a multiplicative model. In a short, there was an interaction between ACE gene and cigarette smoking, alcohol drinking and BMI on EH, especially in a low dose-exposure effect Conclusion It is important for individuals who carry ACE D allele gene to prevent EH, and furthermore, to prevent and control coronary heart disease, in a view of population-based prevention.

Lung cancer risk in never-smokers:An overview of environmental and genetic factors

Lung cancer is the leading cause of cancer-related mortality globally,accounting for 1.8 million deaths in 2020.While the vast majority are caused by tobacco smoking,15%-25%of all lung cancer cases occur in lifelong neversmokers.The International Agency for Research on Cancer(IARC)has classified multiple agents with sufficient evidence for lung carcinogenesis in humans,which include tobacco smoking,as well as several environmental exposures such as radon,second-hand tobacco smoke,outdoor air pollution,household combustion of coal and several occupational hazards.However,the IARC evaluation had not been stratified based on smoking status,and notably lung cancer in never-smokers(LCINS)has different epidemiological,clinicopathologic and molecular characteristics from lung cancer in ever-smokers.Among several risk factors proposed for the development of LCINS,environmental factors have the most available evidence for their association with LCINS and their roles cannot be overemphasized.Additionally,while initial genetic studies largely focused on lung cancer as a whole,recent studies have also identified genetic risk factors for LCINS.This article presents an overview of several environmental factors associated with LCINS,and some of the emerging evidence for genetic factors associated with LCINS.An increased understanding of the risk factors associated with LCINS not only helps to evaluate a never-smoker’s personal risk for lung cancer,but also has important public health implications for the prevention and early detection of the disease.Conclusive evidence on causal associations could inform longer-term policy reform in a range of areas including occupational health and safety,urban design,energy use and particle emissions,and the importance of considering the impacts of second-hand smoke in tobacco control policy.

“Do Big Hands Guide Small Hands?”or“do Small Hands Guide Big Hands”:The intergenerational interactions in environmental behaviors and family influencing factors

Families'large pollution and energy consumption cannot be underestimated.In order to realize and internalize environmental awareness as a social consensus,it is imperative for every member of a household to be involved in transforming everyday behavior.Intergenerational interactions are of paramount importance.Accordingly,the focus of this study was on parent-adolescent interactions,their reciprocal impact on environmental behaviors,and the factors that have an influence on these processes.Questionnaires were employed to collect information of 684 families in 10 districts of Jinan,the capital of Shandong Province.Subsequently,interviews were conducted with 15 of these families to comprehend the tangible reasons underlying intergenerational interactions in environmental behaviors.First,a paired sample T-test was employed to compare the frequency of these interactions.The data showed that while the T values were positive in all eight compared groups,there were significant differences in seven of them.These results suggest that the impact of intergenerational interactions on environmental behaviors is not symmetrical:parents'instructions are far more frequent than adolescents'back-feeding of ecological notions.The interviews revealed that this phenomenon was generated primarily by unequal experiences between parents and adolescents because the latter do not participate in housework and family projects.Furthermore,the traditional concept of intergenerational order appears to be permanent.Second,two linear regression models,a Parent-to-Adolescent model and an Adolescent-to-Parent model that encompassed several factors including family structure,intergenerational relationships,living environment,and families'social class were developed.Among these factors,the intergenerational relationship variable played a particularly significant role:the more equal and open-minded dialogs are incorporated into parent-adolescent communication,the more favorable interactions may occur for development of their environmental behaviors.Thus,when an environmental education system with families is constructed,it is imperative to promote a parent's ecological awareness with the help of grass-roots organizations by means of reasonable rewards and punishments to redress their former behaviors so as to let Big Hands Guide Small Hands.It is also crucial to enhance a more equal intergenerational relationship through parents'schooling or other relevant services so as to create a favorable atmosphere for Small Hands Guide Big Hands.

Study on the interaction between polymorphisms of FOXO3A gene and environmental factors in longevity at Bama county,Guangxi province

Objective: To study the interaction between the polymorphisms of FOXO3A and the environmental factors in the longevity district of Bama county.Methods: Using Taqmaq probe,genotyping of FOXO3A gene was performed for 200 longevous elderly(aged 90-110)and 288 healthy controls(aged 48-89).The interaction between the polymorphisms of gene and environmental factors were analyzed by using conditional logistic regression.Results: Minor allele frequencies(MAF)of five known SNPs in FOXO3A gene were higher in cases than in controls(P<0.05).There was a positive interction between minority alleles of rs2764264 in FOXO3A gene and the environment factors in the longevity district(OR=11.08,γ=1.075).Conclusion: Five SNPs of FOXO3A gene would be closely correlated with human longevity in Bama.The interaction between the polymorphisms of FOXO3A genes rs2764264 and the environment factors in the longevity district had synergy to longevity.The longevity phenomenon in Bama probably was the result of the interaction between gene and environmental factors.

Interaction of methylenetetrahydrofolate reductase C677T,cytochrome P4502E1 polymorphism and environment factors in esophageal cancer in Kazakh population

AIM： To evaluate the association and interaction of genetic polymorphisms in methylenetetrahydrofolate reductase （MTHER） and cytochrome P4502E1 （CY- P4502E1）, environment risk factors with esophageal cancer （EC） in Kazakh, a high EC incidence area of Xinjiang Uygur Autonomous Region, China. METHODS： A 1：2 matched case-control study was conducted with 120 cases of EC and 240 populationor hospital-based controls. The controls were matched for sex, nationality, area of residence and age within a 5-year difference. MTHER and CYP4502E1 genotypes were identified by PCR-based restriction fragment length polymorphism （RFLP）. A conditional logistic regression model was established to identify risk factors. The strata method was adopted in interaction analysis. RESULTS： Low consumption of green vegetables and fresh fruits, alcohol drinking, and unsafe water （shallow well, or river） were found to be the risk factors for EC. Individuals with the MTHFR677 （C/T ＋ T/T） genotype had a 2.62-fold （95% CI： 1.61-4.28） risk of developing EC compared with those who carried the C/C genotype. Individuals with the CYP4502EIC1/C1 genotype had a 3.00-fold （95% CI： 1.82-4.96） risk compared with those who carried the CYP4502E1 （C1/C2 ＋ C2/C2） genotype. Gene-environment interaction analysis showed that MTHFR677 gene polymorphism was correlated with consumption of green vegetables and fresh fruit, while CYP4502E1 C1/C1 was correlated with alcohol drinking and unsafe drinking water. MTHFR and CYP4502E1 analysis of gene-gene interaction showed that individuals with the MTHFR677 （C/T ＋ T/T） and CYP4502EIC1/ C1 genotypes had a 7.41-fold （95% CI： 3.60-15.25） risk of developing EC compared with those who carried the MTHFR677C/C and CYP4502E1 RsaI C1/C2 ＋ C2/C2 genes, and the interaction rate was higher than that of the two factors alone. CONCLUSION： Low consumption of green vegetables and fresh fruits, alcohol drinking, and unsafe water （shallow well, or river） and polymorphisms in MTHFR and CYP4502E1 genes are important risk factors for EC. There is a synergistic interaction among polymorphisms in MTHFR and CYP4502E1 genes and environment factors. MTHFR and CYP4502E1 genes can be used as biomarkers for prevention of EC in Kazakh, Xinjiang Uygur Autonomous Region, China.

Genetic and Genotype × Environment Interaction Effects for Appearance Quality of Rice

This study was conducted to generate genetic information in rice varieties based on a complete diallel crosses over two years. The results indicated that genotype effect was significant for all traits. Genotype × environment interaction effects were significant only for cooked grain length （CGL） and cooked grain shape （CGSH）. General combining ability （GCA） and specific combining ability （SCA） effects were significant for entire traits, which indicated the important roles of both additive and non-additive gene actions. GCA x environment interaction effects were significant for CGL, CGSH and grain elongation index （GEI）. In the controlling of the inheritance of milled grain shape （GSH）, milled grain width （MGW）, GEI, milled grain length （MGL）, CGSH and cooked grain width （CGW）, the additive gene effects were more important than non-additive one. The average degree of dominance was within the range of partial dominance for all of the traits. The narrow-sense heritability was ranged from 0.65 （GSH） to 0.36 （CGL）. GCA effects were significant for all of the parents in milled grain length and it was significant for some of the parents in other traits. The crosses of Deilmani × IRFAON-215 exhibited significant SCA for GEI. The positive mean of heterosis was observed for CGW. The highest maximum values of heterosis were revealed in GEI, flowed by GSH, MGW and CGW. GCA and MPV were significantly and positively correlated together for all traits.

Genetic background effects on QTL and QTL × environment interaction for yield and its component traits as revealed by reciprocal introgression lines in rice

QTLs for quantitative traits are influenced by genetic background(GB) and environment.Identification of QTL with GB independency and environmental stability is prerequisite for effective marker-assisted selection(MAS). In this study, QTLs and QTL × environment interactions affecting grain yield per plant(GY) and its component traits, filled grain number per panicle(FGN), panicle number per plant(PN) and 1000-grain weight(TGW) across six environments were dissected using two sets of reciprocal introgression lines(ILs) derived from the cross Lemont × Teqing and SNP genotypic data. ANOVA indicated that the differences among genotypes and environments within each set of ILs were highly significant for all traits. A total of 72 distinct QTLs for GY and its component traits including 15 for GY, 25 for FGN, 18 for PN, and 29 for TGW were detected over the six environments. Most QTLs(87.4%) showed significant QTL × environment interactions(QEIs) and appeared to be more or less environment-specific. Among 72 QTLs, 15(20.8%) QTLs and 12(16.7%) QEIs were commonly identified in both backgrounds, indicating QTL especially QEI for yield and its component traits had strong GB effects. Four QTL regions affecting GY and its component traits, including S1269707–S4288071, S16661497–S17511092, and S35861863–S36341768 on chromosome 3, and S4134205–S7643153 on chromosome 5, were detected in both backgrounds and coincided with cloned genes for yield-related traits. These regions can be the targeted in rice breeding for high yield potential through MAS. Application of QTL main effects and their environmental interaction effects in MAS was discussed in detail.

Genetic pathways in cerebral palsy:a review of the implications for precision diagnosis and understanding disease mechanisms

Ce rebral palsy is a diagnostic term utilized to describe a group of permanent disorders affecting movement and posture.Patients with cerebral palsy are often only capable of limited activity,resulting from non-progressive disturbances in the fetal or neonatal brain.These disturbances severely impact the child’s daily life and impose a substantial economic burden on the family.Although cerebral palsy encompasses various brain injuries leading to similar clinical outcomes,the unde rstanding of its etiological pathways remains incomplete owing to its complexity and heterogeneity.This review aims to summarize the current knowledge on the genetic factors influencing cerebral palsy development.It is now widely acknowledged that genetic mutations and alterations play a pivotal role in cerebral palsy development,which can be further influenced by environmental fa ctors.Des pite continuous research endeavors,the underlying fa ctors contributing to cerebral palsy remain are still elusive.However,significant progress has been made in genetic research that has markedly enhanced our comprehension of the genetic factors underlying cerebral palsy development.Moreove r,these genetic factors have been categorized based on the identified gene mutations in patients through clinical genotyping,including thrombosis,angiogenesis,mitochondrial and oxidative phosphorylation function,neuronal migration,and cellular autophagy.Furthermore,exploring targeted genotypes holds potential for precision treatment.In conclusion,advancements in genetic research have substantially improved our understanding of the genetic causes underlying cerebral palsy.These breakthroughs have the potential to pave the way for new treatments and therapies,consequently shaping the future of cerebral palsy research and its clinical management.The investigation of cerebral palsy genetics holds the potential to significantly advance treatments and management strategies.By elucidating the underlying cellular mechanisms,we can develop to rgeted interventions to optimize outcomes.A continued collaboration between researchers and clinicians is imperative to comprehensively unravel the intricate genetic etiology of cerebral palsy.

Distribution and influencing factors of microeukaryote in different water layers of the southwestern Indian Ocean Ridge

Microeukaryotes play a vital role in shaping marine ecosystems,especially in marine productivity,the microbial food web,and carbon cycle.The Indian Ocean is one of the largest oligotrophic areas in the world,but little is known about the biodiversity of microeukaryotes in the area.The community composition and geographical distribution of microeukaryotes collected from the surface(SUR)and deep chlorophyll maximum(DCM)layers in the southwestern Indian Ocean were studied using high-throughput sequencing of the 18S rRNA gene.The metagenomic data helped quantify the impact of environmental factors on microeukaryotic communities.The relative abundance of different taxa groups exhibited distinct patterns between SUR and DCM layers,except for the most dominant Dinoflagellata that accounted for more than 40.6%abundance in each sample.Radiolaria was much more abundant in the nutrient-rich DCM layer than the SUR layer.The community similarity of microeukaryotes decreased with increasing of geographic distance,whereas the temperature and inorganic nitrogen were the most important environmental parameters to community structure.Abundant communities were more influenced by dispersal limitations and rare communities were more responsive to environmental factors.Correlation network analyses revealed strong biotic interactions indicative of parasitism,predation and competition,and their contribution to microeukaryotic population in diverse environments.Overall,this study provided insights into the biodiversity of microeukaryotes by characterizing the differences between water layers and identifying the driving factors in the ocean.

Independent and combined effects of environmental factors and miR-126, miR-143, and miR-145 on the risk of coronary heart disease

Objective To evaluate the effects of environmental factors and microRNAs （miRNAs） （miR-126, miR-143, and miR-145） on the risk of coronary heart disease （CHD）. Methods A frequency-matched case-control study （450 patients, 450 controls） was conducted from April 2014 to December 2016 in Fuzhou City, China. Environmental factors were investigated using a self-administered questionnaire, and the expression levels of miR-126, rniR-143, and miR-145 were determined by quantitative real-time Polymerase Chain Reaction （PCR） in pe- ripheral blood mononuclear cells. Unconditional logistic regression models were used for statistical evaluation. Results Alcohol consumption, high-salt diets, high-intensity work, and lack of physical activity were significantly associated with increased CHD risk, whereas light diet was significantly associated with decreased risk. MiR-126, miR-143, and miR-145 were highly expressed in the CHD group compared with the control group. After adjustment for other environmental factors, unconditional logistic regression results revealed that miR-126, miR-143, and depression were the independent risk factors of CHD, and light diet was the independent protective factor of CHD. Conclusions Our data suggest that a family history of CHD, anxiety, and alcohol consumption was significantly associated with increased CHD risk, whereas light diet was significantly associated with decreased risk. Furthermore, miR-126 and miR-143 in combination with several risk factors, could play a joint role in the development of CHD. Therefore, it is necessary to manage patients with CHD in all directions and multiple level.

Genetic, hormonal, and environmental control of tillering in wheat

Tillering contributes greatly to grain yield in wheat.Investigating the mechanisms of tillering provides a theoretical foundation and genetic resources for the molecular breeding of wheat.The regulation of tillering is a complex molecular process that involves a multitude of factors.Little is known about the molecular mechanisms in the wheat genome,although progress has been made in rice.Here we review the developmental characteristics of tillers and summarize current knowledge of the roles of endogenous and environmental factors in wheat tillering.We propose directions for future studies and advanced technologies to be used for gene identification and functional studies.

Non genetic risk factors of long-QT syndrome

The purpose of the present study is to provide guidelines regarding risk factors that may worsen the Long-QT Syndrome (LQTS), based on available literature. This review evaluates the current knowledge on these risk factors of acquired LQTS, with an emphasis on non genetic risk factors, including environmental factors. PubMed was searched for literature in English from 1999 to 2011 on the molecular and clinical studies of Long-QT syndrome. We agree, with recent investigations described in the literature, that variety of factors, inherited or environmental, can influence expression of ion channel proteins with impact on repolarization.

Genetic relationship of rapeseed yield-related traits revealed by elite lines under multiple environments

To provide a theoretical basis for further improvement of Brassica napus yield, additive dominance with additive - by - additive epistatic effects （ ADAA） genetic model and a 6 X 8 partial dial- lel cross design were used to analyze the genetic effects and correlations of five yield related traits of 14 excellent Brassica napus parental lines and their 46 and F2 populations. The results showed that silique density （SD） , siliques per plant （SPP） , seeds per silique （SPS） and thousand - seed weight （TSW） exhibited not only additive and dominant effects, but also significant epistatic effects. The dominant effects of all five yield - related traits were obviously greater than their additive effects and epistatic effects. Yield per plant （YPP） showed significant genetic correlation with SD, SPP and SPS, and the main component of the genetic correlation was the dominance correlation. SPP and SPS both showed a significant negative correlation with TSW. The SD of rapeseed was genetically correlated with all three components of yield to a certain extent, and there were different components of genetic effects positively correlated with the three yield components, indicating that SD is a potential trait to reconcile the conflict between TSW and SPP as well as SPS.

GENETIC MODELS AND ANALYSIS METHODS FOR SEX-LINKED AND MATERNAL GENE EFFECTS

Genetic models are proposed for analyzing sex-linked and maternal effects as well as autosomal gene effects.For the model with no genotype×environment interaction,the total genetic effect is partitioned into direct additive （A）,direct dominance （D）,sexlinked （L）,maternal additive （Am） and maternal dominance （Dm） genetic components.For the model including genotype×environment interaction （GE）,GE can also be partitioned into components of direct additive by environment interaction （AE）,direct dominance by environment interaction （DE）,sex-linked by environment interaction （LE）,maternal additive by environment interaction （AmE ）,and maternal dominance by environment interaction （DmE）.Linear functions of genetic components are listed for parent,F1,and F2.A set of parents,their reciprocal F1’s and F2’s is applicable for efficient analysis.Variance and covariance components can be well mated by MINQUE（O/l） with the jackknife procedure.The t-test conducted by the jackknife procedure is applicable for detecting significance of variation.Adjusted Unbiased Prediction （AUP） method is suggested for predicting genetic effects.

An epidemiologic study of mitochondrial membrane transporter protein gene polymorphism and risk factors for neural tube defects in Shanxi, China

The present study involved a questionnaire survey of 156 mothers that gave birth to children with neural tube defects or had a history of pregnancy resulting in children with neural tube defects （case group） and 156 control mothers with concurrent healthy children （control group） as well as detection of mitochondrial membrane transporter protein gene [uncoupling protein 2 （UCP2）] polymorphism. The maternal UCP2 3＇ untranslated region （UTR） D/D genotype and D allele frequency were significantly higher in the case group compared with the control group （odds ratio （OR） 3.233; 95% confidence interval （C/） 1.103 9.476; P= 0.040; OR： 3.484; 95% CI： for neural tube defects 2.109 5.753; P 〈 0.001）. Univariate and multivariate logistic regression analysis of risk factors for neural tube defects showed that a matemal UCP2 3＇ UTR D/D genotype was negatively interacted with the mothers＇ consumption of frequent fresh fruit and vegetables （S = 0.007）, positively interacted with the mothers＇ frequency of germinated potato consumption （S = 2.15） and positively interacted with the mothers＇ body mass index （S = 3.50）. These findings suggest that maternal UCP2 3＇ UTR gene polymorphism, pregnancy time, consumption of germinated potatoes and body mass index are associated with an increased risk for neural tube defects in children from mothers living in Shanxi province, China. Moreover, there is an apparent gene-environment interaction involved in the development of neural tube defects in offspring.

Range-wide genetic diversity in natural populations of Larix principis-rupprechtii Mayr.

Prince Rupprecht’s larch(Larix principis-rupprechtii Mayr.),a deciduous conifer,widely grows in middle and high elevations of Northern China.Its natural distribution has sharply decreased and has become fragmented,which may have resulted in the loss of genetic variation.In this study,ten natural populations across the entire range of this species were analyzed using amplifi ed fragment length polymorphism markers.A total of 309 loci were detected from 225 individuals of these populations,of which 261(84.5%)were polymorphic.At the species level,the genetic diversity was high(average of the Nei’s genetic diversity H e=0.2602,and Shannon’s information index I=0.3967).The results of molecular variance analysis showed that 90.71%of the genetic diversity occurred within populations.The genetic diff erentiation among populations was moderate as a whole(F ST=0.0929,G ST=0.1510),which is consistent with the moderate level of gene fl ow among populations(N m=2.8116).Based on the unweighted pair group method with arithmetic mean and STRU CTU RE analysis,these populations were grouped into three genetically distinct clusters.The degree of inter-population diff erentiation(G ST=0.1338)for the south group was larger than that for the north group(G ST=0.0915).There was a signifi cant correlation between genetic distance and geographic distance across the species range(r=0.316,P<0.05).Genetic diversity was signifi-cantly associated with longitude but not elevation or climatic factors.The populations with high genetic diversity from each cluster are therefore recommended for future conservation and management of this species.

Estimation of genetic parameters on growth characteristics of a 35-year-old Pinus koraiensis progeny trial in South Korea

The effects of genetic and environmental factors on Pinus koraiensis growth were studied based on a35 year-old progeny trial composed of open-pollinated offspring of twenty-one plus trees.Height,DBH and volume of the offspring was analyzed using restricted maximum likelihood/best linear unbiased prediction in mixed model analysis.Significant site and family effects on the three traits were observed.The distinct growth of offspring by site with disparate climates corroborated the importance of planting species in suitable conditions.Growth differences by family was significant,emphasizing the importance of identifying families with either superior or inferior performance.The parental ranking was assigned in the sites,inferring the breeding value of each plus tree.The estimates of individual heritability(h_(i)^(2))of height,DBH and volume growth were 0.169-0.645,0.108-0.331 and 0.129-0.343 respectively,with higher h_(i)^(2) of the height than DBH on each site.Coefficient of variance of genetic effect was higher with DBH in some cases,indicating the scope for selection is larger for this trait despite the lower heritability compared to height.For the variation between families in terms of the performance stability across sites,consideration of the genotype by environment interaction is required in selecting materials to be used in reforestation with Korean pine.A few families with either superior or inferior performance retained their parental ranking for at least a decade.Other families with increased growth on a particular site were identified,indicating their high breeding value and low stability.Differences in the genetic performance of the families by site requires delineation of the breeding region of the species.

Genetic diversity analysis of Hepatacodium miconioides at different altitude in Tiantai Mountain,Zhejiang Province,China and its relationship with environmental factors

The genetic diversity within and among populations of Hepatacodium miconioides collected at three different altitudes in Tiantai Mountain,Zhejiang Province and its relationships to environmental factors were analyzed by random amplified polymorphic DNA(RAPD)technique.Amplification using 12 random primers of 60 plants and 122 repetitive loci were produced.The percentage of polymorphic loci of three populations ranged from 18.85%to 23.77%with an average of 21.86%,indicating the relatively low genetic diversity of H.miconioides.The average Shannon index of phenotypic diversity(0.1329)and Nei index(0.0925)within populations were relatively low.A distinct genetic differentiation existed among populations of H.miconioides in spite of the relatively small geographical distribution.The average genetic diversity within populations of H.miconioides accounted for 33.58%of the total genetic diversity while the genetic diversity among populations accounted for 66.42%as estimated by the Shannon index of phenotypic diversity,The genetic differentiation among populations of H.miconioides was 0.6546,as estimated by Nei index.The gene flow estimated from GST was only 0.2656 and it indicated that gene flow among populations of H.miconioides was relatively low.The mean value of the genetic identity among populations of H.miconioides was 0.7126 and the average of genetic distance of H.miconioides was 0.3412.The genetic identity between populations at the elevation of 990 m and at the elevation of 780 m was the highest.The genetic identity between population at the elevation 500 m and other two populations was relatively low.The correlation analysis showed that the genetic diversity within populations was significantly related with the soil total nitrogen.