Association between Gene Polymorphisms and SNP-SNP Interactions of the Matrix Metalloproteinase 2 Signaling Pathway and the Risk of Vascular Senescence

Objective This study aimed to explore the association of single nucleotide polymorphisms(SNP)in the matrix metalloproteinase 2(MMP-2)signaling pathway and the risk of vascular senescence(VS).Methods In this cross-sectional study,between May and November 2022,peripheral venous blood of151 VS patients(case group)and 233 volunteers(control group)were collected.Fourteen SNPs were identified in five genes encoding the components of the MMP-2 signaling pathway,assessed through carotid-femoral pulse wave velocity(cf PWV),and analyzed using multivariate logistic regression.The multigene influence on the risk of VS was assessed using multifactor dimensionality reduction(MDR)and generalized multifactor dimensionality regression(GMDR)modeling.Results Within the multivariate logistic regression models,four SNPs were screened to have significant associations with VS:chemokine(C-C motif)ligand 2(CCL2)rs4586,MMP2 rs14070,MMP2rs7201,and MMP2 rs1053605.Carriers of the T/C genotype of MMP2 rs14070 had a 2.17-fold increased risk of developing VS compared with those of the C/C genotype,and those of the T/T genotype had a19.375-fold increased risk.CCL2 rs4586 and MMP-2 rs14070 exhibited the most significant interactions.Conclusion CCL2 rs4586,MMP-2 rs14070,MMP-2 rs7201,and MMP-2 rs1053605 polymorphisms were significantly associated with the risk of VS.

Single Nucleotide Polymorphisms (SNPs) Discovery and Linkage Disequilib-rium (LD) in Forest Trees

With completion of the Populus genome sequencing project and the availability of many expressed sequence tags （ESTs） databases in forest trees, attention is now rapidly shifting towards the study of individual genetic variation in natural populations. The most abundant form of genetic variation in many eukaryotic species is represented by single nucleotide polymorphisms （SNPs）, which can account for heritable inter-individual differences in complex phenotypes. Unlike humans, the linkage disequilibrium （LD） rapidly decays within candidate genes in forest trees. Thus, SNPs-based candidate gene association studies are considered to be a most effective approach to dissect the complex quantitative traits in forest trees. The present study demonstrates that LD mapping can be used to identify alleles associated with quantitative traits and suggests that this new approach could be particularly useful for performing breeding programs in forest trees. In this review, we will describe the fundamentals, patterns of SNPs distribution and frequency, summarize recent advances in SNPs discovery and LD and comment on the application of LD in the dissection of complex quantitative traits in forest tress. We also put forward the outlook for future SNPs-based association analysis of quantitative traits in forest trees.

Single Nucleotide Polymorphisms (SNPs) of URAT1 (rs7932775) and ABCG2 (rs3825016) on Chronic Kidney Disease Patients with Hyperuricemia

Background: More and more chronic kidney disease (CKD) patients are accompanied with hyperuricaemia. As is known, hyperuricaemia is an independent hazard of both cardiovascular diseases (CVD) and chronic kidney diseases. We aim at identifying Single Nucleotide Polymorphism (SNP) difference of hURAT1 (rs7932775) and ABCG2 (rs3825016) on CKD patient with hyperuricemia and/or gout. Methods: All forty-two CKD patients were divided into two groups: hyperuricemia, and control group. 24 hours urine sample and serum were prepared for testing biochemistry parameters. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method is used to analyze hURAT1 and ABCG2 single nucleotide polymorphisms in different groups. Results: 17 patients have CT SNP of hURAT1 (rs7932775) and 13 patients have CT SNP of ABCG2 (rs3825016) in hyperuricemia group, while only 5 persons and 6 persons have the same mutations in control group respectively. 7 patients have CT SNP of both hURAT1 (rs7932775) and ABCG2 (rs3825016) in hyperuricemia group, while only 2 persons have the same mutations in control group. CT mutation rates of hURAT1 (rs7932775) and ABCG2 (rs3825016) in hyperuricemia group were 60.7% (17/28) and 50% (13/28) respectively, higher than that of control group (35.7% (5/14) and 42.8% (6/14)). What is more, Double SNP mutations in both hURAT1 (rs7932775) and ABCG2 (rs3825016) in hyperuricemia group were 25% (7/28), higher than that of control group (14.2%, 2/14). Conclusion: There are higher mutation rates of CT SNP in hURAT1 (rs7932775) and/or ABCG2 (rs3825016) in hyperuricemia group. We can conclude that hyperuricemia is a high risk factor in progress of CKD, which is necessary to take measures of decreasing serum uric acid to delay CKD progress.

Digital Barcode Development for Single Nuclotide Polymorphism (SNP) Identification of Suzhong Swine Individuals

Suzhong swine is a hybrid breed derived from Taihu sows and Landraee boars. To identify Suzhong swine individuals and trace the source of pork products, single nucleotide polymorphisms （SNPs） identification of Suzhong swine individuals was studied. A total of 29 pairs of primers were designed and sev- en pairs of primers were used for identification of Suzhong swine individuals. The products amplified by seven pairs of primers could be directly sequenced, with clean sequencing map background and no ambiguity in sequence read. Totally 52 SNPs loci were amplified by seven pairs of primers, and 41 SNPs loci were reserved for identification of Suzhong swine individuals through correlation analysis and heterezygosity filtration （ H ≥0.1 ）. Meantime, the digital barcodes for SNP identification of 96 individuals of Suzhong swine derived from seven boars and 12 sows were developed, which well distinguished 96 individuals of Suzhong swine. Theoretically, 41SNPs amplified by seven pairs of primers could be used for identification of 5.0 × 10^6 pig individuals. Therefore, digital barcode devel- opment method for SNP identification of Suzbong swine individuals can be used for individual identification of Suzhong swine in scale pig farm and meat product traceability.

Development of organelle single nucleotide polymorphism (SNP) markers and their application for the identification of cytoplasmic inheritance patterns in Pyropia yezoensis (Bangiales,Rhodophyta)

The genus Pyropia contains several important cultivated species.Genetic research in nori species has mainly focused on the cell nucleus,with few studies on organelles(chloroplast and mitochondria).Due to the high copy numbers of organelles in cells,which influence the development and traits of algae,it is necessary to study their genetic mechanism.In this study,the marine red alga Pyropia yezoensis,an important economic macroalga,was selected as the study object.To investigate organelle(chloroplast and mitochondria)inheritance in P.yezoensis,the wild type RZ(maternal strain)was crossed with the red mutant HT(paternal strain)and 30 color-sectors from 11 F1 gametophytic blades were examined.The complete chloroplast and mitochondrial genomes of the red mutant(HT)were assembled for the first time.One reliable and stable single nucleotide polymorphism(SNP)loci filtrated by bioinformatics analysis was used as a molecular marker for chloroplast and mitochondrial DNA,respectively,in subsequent experiments.PCR amplification and sequence analysis showed that the haplotypes of color-sectors detected were consistent with those of the maternal parent,confirming that both chloroplast and mitochondrial genomes were inherited maternally in P.yezoensis.The inheritance pattern of organelles in P.yezoensis can be used to guide the hybridization and breeding of nori.Additionally,the organelle SNP markers developed in this study can be applied in subsequent genetic research.

Maternal TMPRSS6 Gene Polymorphism rs855791SNP in Women with Preeclampsia

Introduction: Preeclampsia can lead to several maternal and perinatal adverse effects. There are few published data on the association between transmembrane serine protease 6 (TMPRSS6) gene polymorphism and preeclampsia. Objective: To assess the association between TMPRSS6 gene polymorphism rs855791SNP in women with preeclampsia compared with healthy pregnant women. Method: A case-control study (60 women in each arm) was conducted at Saad Abuaela Maternity Hospital in Khartoum, Sudan. Sociodemographic and clinical data were gathered through a questionnaire. The participant was genotype for TMPRSS6 gene rs855791SNP using Polymerase Chain Reaction and Restriction Fragment Length Polymorphism (PCR-RFLP). The results were confirmed by DNA sequencing. Result: There was no significant difference in the median of age, parity, and body mass index. The distribution of the genotypes and alleles of TMPRSS6 rs855791 was consistent with the HWE. The overall TMPRSS6 rs855791 polymorphism was not significantly associated with preeclampsia. However, the proportion of heterozygotes (TC) was considerably higher in the women with preeclampsia (46.7%) than in the control group (23.3%) (p = 0.001;OR = 2.71;95% CI = 1.21 - 6.07). The proportion of homozygotes (TT) and T alleles was not significantly different between women with preeclampsia and the control group. Conclusion: The overall TMPRSS6 rs855791 polymorphism was not significantly associated with preeclampsia and healthy control.

基于多重PCR靶向测序的烟草1.8K SNP育种液相芯片的开发与应用

本研究根据公开发表的烟草K326基因组和烟草430K SNP固相芯片检测数据,以7份种质两两组合之间每条染色体上20个多态标记为目标,基于多重PCR扩增的精准定位测序分型技术(mGPS,Genotyping by Pinpoint Sequencing of multiplex PCR products)开发出烟草1.8K育种液相芯片(YT1.8K.1)。利用该芯片对上述7份种质两两之间杂交的21个杂交组合进行基因分型检测,每个杂交组合之间的平均差异位点数为650个,能同时满足每个组合定向改良筛选高遗传背景回复率单株的需要。利用该芯片对23个烟草品种进行基因型分型检测和聚类分析,聚类分类结果与品种系谱基本吻合;利用该芯片从367个BC2F1群体中筛选出5个背景回复率高于94.96%的单株,高于理论均值87.5%,表明该育种芯片可应用于烟草种质资源聚类分析、定向改良育种的遗传背景筛选。

Association of-238G/A and -857C/T Polymorphisms of Tumor Necrosis Factor-Alpha Gene Promoter Region With Outcomes of Hepatitis B Virus Infection

Objectives To determine whether -238G/A and -857C/T polymorphisms of tumor necrosis factor-alpha （TNF-o0 gene promoter were associated with outcomes of hepatitis B virus infection. Methods A total of 246 HBV self-limited infected subjects and 443 chronic hepatitis B （HB） patients were recruited in this case-control study. TNF-α-238G/A and -857C/T gene promoter polymorphisms were examined by polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP）. Results The frequency of TNF-α-238 GG （90.7%） in chronic HB group was significantly lower than that （95.1%） in self-limited group （P=0.041）. The frequency of TNF-oc-857 CC （79.7%） in chronic HB patients was significantly higher than that （70.9%） in self-limited infected subjects （P=0.021）. Multiple logistic regression analysis revealed that both TNF-oc-238GA and -857CC were independently associated with chronic HB. Conclusions TNF-α promoter variants are likely to play a substantial role in influencing the outcomes of HBV infection.

Associations of Gonadotropin-Releasing Hormone Receptor (GnRHR) and Neuropeptide Y(NPY) Genes’Polymorphisms with Egg-Laying Traits in Wenchang Chicken

Single nucleotide polymorphisms （SNP） of chicken gonadotropin-releasing hormone receptor （GnRHR） and neuropeptide Y （NPY） were selected to identify the genotypes of Wenchang （Chinese indigenous breed） chicken with restricton fragment length polymorphisms. The associations of the SNPs with the total egg production （NE）, average days of continual laying （ADCL）, and number of double-yolked eggs （DYE） traits were analyzed. The frequency of restriction enzyme A/a alleles in the population was for GnRHR 0.69 （Bpu1102 Ⅰ A） and 0.31 （Bpu1102 Ⅰ a） and for NPY 0.46 （Dra Ⅰ B） and 0.54 （Dra Ⅰ b）. Trait data from a total of 120 hens, which were purebred introduced from Hainan Province, China from one generation were recorded. Two significant effects of genes＇ marker were found： for GnRHR and number of eggs （dominant; t= 2.67, df= 116） and NPY and number of eggs （additive; t= 1.97, df= 116）. The current research supports the effects of GnRHR and NPY genes on egg-laying traits of chickens.

A case-control study about the association between vascular endothelial growth inhibitor gene polymorphisms and breast cancer risk in female patients in Northeast China

Objective： The inhibition of the neovascularization in tumors is a potential therapeutic target of cancer. Vascular endothelial growth inhibitor （VEGI） is a member of the TNF superfamily which has the ability to suppress the formation of new vessels in tumors. In order to study the association between VEGI gene polymorphisms and breast cancer risk, a case-control study was conducted in Chinese Han women in Northeast China. Methods： Our study involved 708 female breast cancer patients and 685 healthy volunteers. Four SNPs of VEGI gene were analyzed through the polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） method. The association between VEGI gene polymorphisms and breast cancer risk was analyzed in our study. The relation between VEGI gene variants and clinical features of breast cancer including lymph node （LN） metastasis, esl^ogen receptor （ER）, progestrogen receptor （PR）, tumor protein 53 （1953）, human epidermal growth factor receptor 2 （Her-2） and triple negative （ER-/PR-/Her-2-） status was analyzed as well. Results： We found that the CT genotype and T allele of rs6478106 were more frequent in patients than in controls. There was also a statistical difference in the distribution of Crs6478106Grs4263839 haplotype between patients and controls. In addition, SNP rs6478106 and rs4979462 were related with the Her-2 status. Conclusions： Our results suggest that VEGI gene variants may be related to the breast cancer risk and the clinical features of breast cancer in Chinese Han women in Northeast China.

Expression analysis,single nucleotide polymorphisms within SIRT4 and SIRT7 genes and their association with body size and meat quality traits in Qinchuan cattle

Silent information regulator 2 （Sir2） proteins, or sirtuins, are nicotine adenine dinucleotide （NAD）-dependent deacetylases that connect metabolism with longevity in lower organisms. In mammals, there are seven Sir2 homologs, namely, silent information regulators （SIRT1-7）. SIRT4 and SIRT7 genes play a crucial role in regulating lipid metabolism, cellular growth and metabolism. This suggests that they are potential candidate genes for affecting body size and meat quality traits in animals. Hence, this study aimed to detect genetic variations of both SIRT4 and SIRT7 bovine genes in Qinchuan cattle, and to evaluate the effect of these variations on economically important body size and meat quality traits. Expression analysis using quantitative real-time PCR （qPCR） indicated that SIRT4 and SIRT7 were broadly expressed in all thirteen studied tissues. The expression of SIRT4 was higher in liver, muscle, and in subcutaneous fat tissue. In the case of SIRT7, the expression was higher in lung, abomasum, and subcutaneous fat. Using DNAsequencing, a total of three single nucleotide polymorphisms （SNPs） were identified within SIRT4 and SIRT7 genes in 468 Qinchuan cattle. These included one novel SNP within 3＇ untranslated regions （UTR） of SIRT4 （SNP1： g. 13915A〉G） and two novel synonymous substitutions in SIRT7 （SNP2： g.3587C〉T and SNP3： g.3793T〉C）. Statistical analyses indicated that all three SNPs could significantly influence some body size and meat quality traits in Qinchuan cattle. These novel findings will provide a background for application of bovine SIRT4 and SIRT7 genes in the selection program of Chinese cattle.

Improved Allele-specific Polymerase Chain Reaction for Single Nucleotide Polymorphism Genotyping

An improved allele-specific PCR（AS-PCR） approach was applied to investigating -55C/T polymorphism in promoter region of the uncoupling protein 3（UCP3）gene. AS-PCR is a competitive PCR method which is based on positioning the 3＇ base of a PCR primer to match one single nucleotide polymorphism（SNP） allele and accurately extend only the correctly matched primer. But it is limited in use because of its poor specificity. In this study, we improved the specificity of AS-PCR by introducing additional mismatch at the penultimate base of 3＇ end of AS-PCR primer in combination with decreasing the level of dNTP in the reaction mixture. Sensitivity, specificity and reliability of this method were assessed for both simple plasmid model and complex human genomic SNP targets. The -55C/T（rs1800849） polymorphisrn of the UCP3 gene was analyzed via this AS-PCR and restriction fragment length polymorphism（RFLP）, the latter was used as a gold standard. The results suggest that the increase in AS-PCR discrimination with this method should facilitate the use of this simple, rapid, and inexpensive technique for SNP genotyping application.

Relationship between nerve injury-induced protein gene 2 polymorphism and stroke in Chinese Han population

The aim of present study was to investigate the relationship between nerve injury-induced protein 2 （NINJ2） gene polymorphism and stroke in Chinese Han population. Fifty-two patients with large-artery atherosclerosis （LAA） infarction, 85 patients with small-artery occlusion lacunar （SAO） infarction, 50 patients with intracerebral hemorrhage （ICH） and 66 controls were included. Genotypes and alleles frequencies of the two single nucleotide polymorphisms （SNPs） of NINJ2 among different groups were analyzed and compared. In regard to rs12425791, the frequencies of the AG and AA＋AG genotypes of the LAA and SAO groups were significantly higher than those in the control group; the frequency of the A allele of the SAO group was significantly higher than that of the control group. In regard to rs11833579, there were not any significant differences between the case and the control groups. The SNP rs12425791 is significantly associated with ischemic stroke, and the A allele increases the susceptibility to stroke. The SNP rs11833579 is not significantly associated with stroke.

A single nucleotide polymorphism in SPA TA17 may be a genetic risk factor for Japanese patients with meiotic arrest

Genetic mechanisms have been implicated as a cause of some cases of male infertility. Recently, 10 novel genes involved in human spermatogenesis were identified by microarray analysis of human testicular tissue. One of these is spermatogenesis-associated 17 （SPATA17）. To investigate whether defects in the SPATA17 gene are associated with azoospermia due to meiotic arrest, a mutational analysis was conducted, in which the SPATA17 coding regions of 18 Japanese patients with this condition were sequenced. A statistical analysis was carried out that included 18 patients with meiotic arrest, 20 patients with Sertoli-cell-only syndrome （SCOS） and 96 healthy control men. No mutations were found in SPA TA17. However, three coding single nucleotide polymorphisms （cSNPs： SNP 1-SNP3） were detected in the patients with meiotic arrest. No significant differences in the genotype or allele frequencies of SNP1 and SNP2 were found between patients with meiotic arrest and the others. However, the frequency of the SNP3 allele was significantly elevated in the meiotic arrest group （P 〈 0.05）. This study suggests that SPATA17 may play a critical role in human spermatogenesis, especially in meiosis.

Single nucleotide polymorphisms in intron 1 and intron 2 of Larimichthys crocea growth hormone gene are correlated with growth traits

The growth hormone gene (GH) affects animal growth and is a potential target for genetic studies of variation related to growth traits. In this study, we analyzed single nucleotide polymorphisms (SNPs) in GH intron regions and their associations with growth traits in large yellow croaker, Larimichthys crocea, from Zhejiang and Fujian stocks. The results of PCR-single strand conformation polymorphism showed two haplotypes of intron 1, named AA and AB genotypes, in Zhejiang stock. AB exhibited an SNP at position 196 (G A) that was negatively correlated with body height and positively correlated with standard length/body height (P 0.05). Two different genotypes, CC and CD, were identified in intron 2 in Fujian stock, with CD showing an SNP at position 692 (T C). The CD genotype had a significantly positive correlation with both weight and total length (P 0.01). These basic data highlight the potential for using GH as a genetic marker of fish growth in marker assisted selection.

ENPP1/PC-1 Gene K121Q Polymorphism Is Associated with Obesity in European Adult Populations: Evidence from A Meta-Analysis Involving 24 324 Subjects

Objective Findings from the previous studies have suggested a relationship between ectonucleotide pyrophosphatase /phosphodiesterase 1 （ENPP‐1） or plasma cell membrane glycoprotein 1 （PC‐1） gene single nucleotide polymorphism （K121Q, rs1044498） and genetic susceptibility to obesity. However, such relationship is not reproduced by some currently available studies. In this context, the present study is aimed to quantitatively analyze the association of K121Q variant with obesity in all published case‐control studies in European adult populations. Methods Published literature from PubMed, EMBASE, and ISI web of science databases were retrieved. The studies evaluating the association of ENPP1/PC1 gene K121Q polymorphism with obesity were included, in which sufficient data were presented to calculate the odds ratio （OR） with 95% confidence intervals （CIs）. Results Ten case‐control studies meeting the inclusion criteria identified a total of 24,324 subjects including 11,372 obese and 12,952 control subjects. The meta‐analysis results showed a statistically significant association of K121Q with obesity [OR （95%CI）： 1.25 （1.04‐1.52） P=0.021] under a recessive model of inheritance （QQ vs. KK＋KQ） without heterogeneity or publication bias. Conclusions The results from the present study have indicated that ENPP1/PC1 Q121 variant may increase the risk of obesity and that more well‐designed studies based on a larger population will be required to further evaluate the role of ENPP1/PC1 gene K121Q polymorphism in obesity and other related metabolic syndromes.

<i>Endopolygalacturonase</i>Gene Polymorphisms: Asset of the Locus in Different Peach Accessions

Endopolygalacturonase (endoPG) plays a pivotal role in determining peach [Prunus persica L. (Batsch)] fruit characteristics. Different Pp-endoPG genes or allelic variants have been described, characterized by different polymorphisms: insertions-deletions (InDels) and single nucleotide polymorphisms (SNPs). Eighty-five peach accessions (comprising commercial cultivars, F1 progenies of selected crosses, and three haploid seedlings) with different flesh softening patterns (Non Melting: NM;Melting: M;Slow Softening: SS;Stony Hard: SH) were screened by exploiting specific polymorphisms, with the aim to characterize their asset at the endoPG locus and evaluate a potential relationship with fruit flesh texture phenotype. The results of InDel analysis allowed to distinguish, by a simple genotyping procedure, NM flesh phenotypes from the others. Further information arose from this analysis, showing that two Pp-endoPG genes, i.e., Pp-endoPGm (Ppa006839m), involved in the determination of the Melting/Non Melting trait, and Pp-endoPG_M (Ppa006857m), involved in the determination of the Clingstone/Freestone trait, always co-segregate, and that SS Big Top possesses a “null” Pp-endoPG allele. Cleaved Amplified Polymorphic Sequence (CAPS) analysis allowed to preliminarily discriminate the Pp-endoPG variants of the SS and SH accessions considered. The integrated use of the considered polymorphisms in a high number of peach accessions proved useful, by individuating the different gene variants and their combinations, to describe the structure of the endoPG locus in different genotypes.

Single Nucleotide Polymorphisms in a Male Infertility-Related Gene CatSper

Objective To identify single nucleotide polymorphisms (SNPs) of human CatSper gene, themouse homologous gene product, which plays a crucial role in mouse male sterility.Methods We demonstrated a systematic screening of SNPs in coding regions and flankingintronic regions of human CatSper gene in a sample subset from a total 210 male individuals byDNA sequencing. Then we used PCR single-strand conformation polymorphism (SSCP) analy-sis to determine the allele frequencies of the possible SNPs among the whole 210 Chinese Hanmale individuals.Results Three SNPs, including two novels, were identified and their allele frequencies weredetermined in the 210 Chinese Han male individuals. These SNPs were assembled into largeSNP database that promises to enable the dissection of the genetic basis of disease.

Association between single nucleotide polymorphisms on chromosome 17q and the risk of prostate cancer in a Chinese population

In European populations,7 single nucleotide polymorphisms(SNPs) on chromosome 17q,3 SNPs on 17q12,and 4 SNPs on 17q24.3 were recently identified to be closely related to the risk of prostate cancer by a genome-wide association study.In Japanese populations,the correlation between 2 SNPs on 17q and the risk of prostate cancer and tumor aggressiveness was also confirmed by a large-scale experiment.However,whether 17q is associated with prostate cancer and its clinical manifestations in Chinese populations is still unknown.Therefore,we conducted a case-control study in a northern Chinese population and tested 2 SNPs,rs4430796 and rs1859962,on 17q in 124 prostate cancer patients and 111 controls using polymerase chain reaction-high resolution melting curve(PCR-HRM) combined with sequencing.We analyzed the association of the 2 SNPs with the risk of prostate cancer as well as patients' lifestyles,onset ages,Gleason scores,PSA levels,and pathologic stages.We found a significant difference in the G allele of SNP rs1859962(P = 0.035,OR = 1.51,95% CI = 1.03-2.21) but not in the rs4430796 genotype frequency or allele frequency distribution between prostate cancer patients and the controls(P > 0.05).Neither of the SNPs was significantly associated with the onset age,Gleason score,PSA level,pathologic stage,or other clinical indicators of patients with prostate cancer(P > 0.05).Our results show that polymorphism of the G allele of SNP rs1859962 is associated with the risk of prostate cancer in a Chinese population.

bHLH genes polymorphisms and their association with growth traits in the Pacifi c oyster Crassostrea gigas

The basic helix-loop-helix(bHLH)genes encode a large superfamily of transcription factors in the Pacific oyster(Crassostrea gigas),and play a very important role in regulation of growth and development.To investigate the oyster growth traits and the associations with bHLH genes variations,we analyzed the gene polymorphisms-traits association in a wild population,and confirmed the results in another independent wild population by targeted gene re-sequencing and SNPshot analysis.After screening the single nucleotide polymorphisms(SNPs)in three candidate genes of the bHLH family(88 bHLH genes in two wild oyster populations in total),we identified the allele CgLoblHLH4-T/G located in the exon of the CgLoblHLH4 gene.This allele is a non-synonymous mutation(Phe/Leu)with an extremely significant association with shell width(P<0.01)and allele G is beneficial to shell width.This SNP on the CgLoblHLH4 gene might have a potential value as a genetic marker of growth traits that could be used in breeding in C.gigas in the future.