Genetic Analysis of Embryo Production Frequency in Wheat × Maize Cross

A DH population derived from C49S-87/01Y1-1069 was used to study the inheritance of wheat haploid embryo production frequency（EPF） in wheat × maize cross with the mixed major gene and polygene inheritance model of quantitative traits. The results showed that the EPF of wheat × maize cross was controlled by two dominant epistatic genes and polygene with gene effects of 1.95 for the first major gene, 6.69 for the second one and 2.80 for the polygene. The inheritability of major genes was as high as 72.09%, suggesting that the differences in EPF among wheat materials were mainly influenced by genotype. However, non-genetic factors were still important, especially for wheat materials with low EPF.

Changes in plasma calcitonin gene-related peptide and serum neuron specific enolase in rats with acute cerebral ischemia after low-frequency electrical stimulation with different waveforms and intensities

Following acute cerebral ischemia in rats, plasma calcitonin gene-related peptide decreased and the level of serum neuron specific enolase and the volume of the infarction increased. Square-wave and triangular-wave electrical stimulation with low or high intensities could increase the plasma calcitonin gene-related peptide, decrease the serum neuron specific enolase and reduce the infarction volume in the brain in rats with cerebral ischemia. There was no significant difference between different wave forms and intensities. The experimental findings indicate that low-frequency electrical stimulation with varying waveforms and intensities can treat acute cerebral ischemia in rats.

A Study on the Association Between Siglec-1 Gene Polymorphism and Susceptibility in Patients with Chronic Obstructive Pulmonary Disease in Luohe Area

Objective:To analyze the association between Siglec-1 gene polymorphism and susceptibility to chronic obstructive pulmonary disease(COPD)in the population of the Luohe area.Methods:A case-control study(150 COPD patients and 150 healthy controls)was conducted to analyze the Siglec-1 allele in two groups of individuals using single nucleotide polymorphism(SNP)high-throughput detection technology,and the frequencies of each allele were compared.Results:The frequency of rs611847 heterozygous A/G genotype in COPD patients was significantly lower in females than in healthy controls(OR=0.282,95%CI=0.085-0.938,P=0.039);among smokers,the frequency of rs3859664 and rs6084444 genotypes in COPD patients was significantly higher than that in the healthy control group(OR=2.028,95%CI=1.111-3.704,P=0.021;OR=1.836,95%CI=1.033-3.262,P=0.038).Conclusion:Among the COPD population in the Luohe area,there is a significant correlation between the genotypes of three SNPs loci,rs3859664,rs6084444,and rs611847 and susceptibility to COPD in different subgroups of the population.The rs3859664 A/G-A/A and rs6084444 A/G-G/G genotypes can increase the risk of COPD in smokers;the rs611847 heterozygous A/G genotype can reduce the risk of COPD in both female and smoking populations.

宁夏回族MNS、Lutheran、Kell红细胞血型系统基因频率调查研究

目的探究宁夏回族MNS、Lutheran、Kell红细胞血型系统主要抗原基因频率的分布特征。方法采用实时荧光定量聚合酶链反应对140份宁夏回族MNS、Lutheran、Kell红细胞稀有血型系统抗原基因进行分型和多态性分析。结果宁夏回族MNS、Lutheran及Kell血型系统基因呈多态性分布。各血型系统基因型分布的观察值与期望值比较,差异均无统计学意义(P>0.05)。符合Hardy-Weinberg定律,宁夏回族的血型基因频率在世代间保持相对稳定。血型抗原对偶抗原不配合率由高至低分别为M/N抗原(37.37%)、S/s抗原(12.91%)、K/k抗原(1.41%)、Lu a/Lu b抗原(0.71%)。宁夏回族与内蒙古蒙古族、海南黎族、新疆哈萨克族、西藏藏族及四川彝族M和N等位基因频率比较,差异均有统计学意义(P<0.05);宁夏回族与海南黎族、新疆哈萨克族、新疆维吾尔族、西藏藏族S和s等位基因频率比较,差异均有统计学意义(P<0.05)。宁夏回族Lutheran血型系统Lu a和Lu b等位基因与其他民族比较,差异均无统计学意义(P>0.05),但其他民族均为Lu b纯合子,宁夏回族中发现Lu a等位基因少量分布,宁夏回族Lutheran血型系统等位基因频率具有自身分布特点。宁夏回族Kell血型系统K和k等位基因频率与不同民族比较,差异均无统计学意义(P>0.05)。结论宁夏回族MNS、Lutheran、Kell血型系统基因呈多态性分布。宁夏回族MNS抗原不配合率较高,有必要在该地开展MNS血型抗原筛选,对孕产妇及反复多次输血者开展精准输血,避免不规则抗体导致胎儿新生儿溶血病、交叉配血困难延误救治情况的发生。

APC and K-ras gene mutation in aberrant crypt foci of human colon

AIM:To study the genetic alteration in ACF and to define the possibility that ACF may be a very early morphological lesion with molecular changes,and to explore the relationship between ACF and colorectal adenoma even carcinoma. METHODS: DNA from 35 CRC, 15 adenomas, 34 ACF and 10 normal mucus was isolated by means of microdissection. Direct gene sequencing of K-ras gene including codon 12, 13 and 61 as well as the mutation cluster region (MCR) of APC gene was performed. RESULTS: K-ras gene mutation frequency in ACF, adenoma and carcinoma was 17.6% (6/34), 13.3% (2/15), and 14.3% (5/35) respectively, showing no difference (P 】 0.05) in K-ras gene mutation among three pathologic procedures. The K-ras gene mutation in adenoma, carcinoma and 4 ACF restricted in codon 12 (GGT GAT), but the other 2 mutations from ACF located in codon 13 (GGC GAC). K-ras gene mutation was found more frequently in older patients and patients with polypoid cancer. No mutation in codon 61 was found in the three tissue types. Mutation rate of APC gene in adenoma and carcinoma was 22.9% (8/35) and 26.7% (4/15), which was higher than ACF (2.9%) (P 【0.05). APC gene mutation in carcinoma was not correlated with age of patients, location, size and differentiation of tumor. CONCLUSION: ACF might be a very early morphological lesion in the tumorogenesis of colorectal tumor. The morphological feature and gene mutation status was different in ACF and adenoma. ACF is possibly putative microadenoma that might be the precursor of adenoma. In addition, the development of a subgroup of colorectal carcinomas might undergo a way of normal epithelium ACF carcinomas .

Transferring a Gene Expression Cassette Lacking the Vector Backbone Sequences of the 1Ax1 High Molecular Weight Glutenin Subunit into Two Chinese Hexaploid Wheat Genotypes

1Ax1 high molecular weight glutenin subunit （HMW-GS） gene expression cassette （GEC） lacking vector backbone sequences together with selectable marker Bar GEC were co-transformed into Chinese hexaploid cultivars Een 1 and Emai 12 to test the feasibility and the efficiency of explant regeneration, transformation frequency and transgene expression comparing with whole vector transformation by the approaches of plasmid extraction and excision, immature embryo isolation, particle co-bombardment, tissue culture, DNA extraction, PCR amplification, southern hybridization, leaf-painting test and SDS-PAGE etc. No significant difference was shown in tissue culture response of the proportion of embryogenic calli, somatic embryogenesis and regeneration frequency between GEC and whole plasmid bombarded embryos, but both regenerated less well than non-bombarded control. Total 56 plantlets that survived PPT selection had insertion of at least the Bar gene, 18 were from the GEC treatment and 38 from the whole plasmid treatment, the escape ratio averaged 0.23. Six independent transplants f230 - f235 with GEC transformation from genotype Emai 12 presented clear PCR amplification bands of Bar and 1Ax1 gene. The transformation and co-transformation frequency were 3.51 and 100% respectively. PCR amplification using a primer-pair specific for ampicillin resistant gene indicated the existence of Amp^R gene in whole vectors but the removal in GECs and transplants. Southern blot of total DNA and PCR products from transgenic plants of 1Ax1 GEC confirmed the integration of the transgene 1Ax1 and the absence of the EcoR Ⅰ recognition site at both ends of the 1Ax1 GEC when integrated. SDS-PAGE showed the expression of 1Ax1 GEC and un-expression of whole plasmid. The length of integrated fragment, the proportion of the gene of interest （GOI） and the selectable marker （MG）, bombardment pressure and genotypes are vital for the expression of a transformed GEC.

Association of Graves’ disease and Graves’ ophthalmopathy with the polymorphisms in promoter and exon 1 of cytotoxic T lymphocyte associated antigen-4 gene

Objective: To investigate the association of Graves’ disease and Graves’ ophthalmopathy with the C/T transition polymorphism at position –318 of promoter and the A/G transition polymorphism at position 49 of exon 1 within cytotoxic T lymphocyte associated antigen-4 (CTLA-4) gene. Methods: Thirty-three patients with ophthalmopathy of Graves’ disease, fifty-six Graves’ patients without ophthalmopathy and sixty normal subjects as control were involved in the present case-control study. The polymorphisms were evaluated by polymerase chain reaction fragment length polymorphism (PCR-RFLP). Com-parisons were made of gene frequencies and allele frequencies between the groups. Results: The gene frequencies of CT and allele frequencies of T were much higher in Graves’ patients with ophthalmopathy than that in the group without ophthalmopathy (P=0.020, P=0.019). The gene frequencies of GG and allele frequencies of G in patients with Graves’ disease were significantly increased as compared with control group (P=0.008, P=0.007). The data suggest that smokers with Graves’ disease seemed to be more predisposed to ophthalmopathy than non-smokers (P=0.018). Conclusion: Our results suggest that an allele of T at position –318 of promoter is associated with genetic susceptibility to Graves’ ophthalmopathy while an allele of G at position 49 of exon 1 is associated with genetic susceptibility to Graves’ disease instead. Smoking is believed to be a major risk factor for ophthalmo-pathy.

Polymorphism of HIV-1 Resistance Genes in Dai and Jingpo Minorities of Yunnan Province

Objective To investigate the mutant frequency and polymorphism of HIV-1 resistanceCCR5-Δ32, CCR2-64I, SDF1-3’A alleles in Jingpo and Dai nationalities of YunnanMethods The study population included 101 Dai and 113 Jingpo ethnical subjects.The genotypes were respectively detected by polymerase chain reaction (PCR) or byPCR/RFLP (restriction fragment length polymorphism) assay. Mutant frequencies werecalculated and allelic polymorphism of the three genes in population was analyzed byU test.Results We didn’t find CCR5-Δ32 mutant in either Dai or Jingpo nationality. In Daiminority, the allele frequency of CCR2-64I was 21.00% and that of SDF1-3’Awas 20.30%. In Jingpo minority, the allele frequency of CCR2-64I was 16.37% and thatof SDF1-3’A was 17.70%.Conclusion Dai and Jingpo nationality of Yunnan might have a high genetic suscep-tibility to HIV-1 (including R5 and X4 HIV strains) since we didn’t find CCR5-Δ32 andthe frequency of SDF1-3’A was much lower than that of Han nationality as wasreported in other research papers.

Cytochrome P450 2E1 genetic polymorphism and gastric cancer in Changle,Fujian Province

AIM: Genetic polymorphism in enzymes of carcinogen metabolism has been found to have the influence on the susceptibility to cancer. Cytochrome P450 2E1 (CYP2E1) is considered to play an important role in the metabolic activation of procarcinogens such as N-nitrosoamines and low molecular weight organic compounds. The purpose of this study is to determine whether CYP450 2E1 polymorphisms are associated with risks of gastric cancer. METHODS: We conducted a population based case-control study in Changle county, Fujian Province, a high-risk region of gastric cancer in China. Ninety-one incident gastric cancer patients and ninety-four healthy controls were included in our study. Datas including demographic characteristics, diet intake, and alcohol and tobacco consumption of individuals in our study were completed by a standardized questionnaire.PCR-RFLP revealed three genotypes:heterozygote (C1/C2) and two homozygotes (C1/C1 and C2/C2) in CYP2E1. RESULTS: The frequency of variant genotypes (C1/C2 and C2/C2) in gastric cancer cases and controls was 36.3% and 24.5%, respectively. The rare homozygous C2/C2 genotype was found in 6 individuals in gastric cancer group(6.6%), whereas there was only one in the control group (1.1%). However, there was no statistically significant difference between the two groups (two-tailed Fisher's exact test P=0.066). Individuals in gastric cancer group were more likely to carry genotype C1/C2 (odds ratio, OR=1.50) and C2/C2 (OR=7.34) than individuals in control group (chi(2) =4.597, for trend P=0.032). The frequencies of genotypes with the C2 allele (C1/C2 and C2/C2 genotypes) were compared with those of genotypes without C2 allele (C1/C1 genotype) among individuals in gastric cancer group and control group according to the pattern of gastric cancer risk factors. The results show that individuals who exposed to these gastric cancer risk factors and carry the C2 allele seemed to have a higher risk of developing gastric cancer. CONCLUSION: Polymorphism of CYP2E1 gene may have some effect in the development of gastric cancer in Changle county, Fujian Province.

Rapid gene expression change in a novel synthesized allopolyploid population of cultivated peanut×Arachis doigoi cross by cDNA-SCoT and HFO-TAG technique

AIIopolyploidy has played an important role in plant evolution and heterosis. Recent studies indicate that the process of wide hybridization and （or） polyploidization may induce rapid and extensive genetic and epigenetic changes in some plant species. To better understand the allopolyploidy evolutionism and the genetic mechanism of Arachis interspecific hybridization, this study was conducted to monitor the gene expression variation by cDNA start codon targeted polymorphism （cDNA-SCoT） and cDNA high-frequency oligonucleotide-targeting active gene （cDNA-HFO-TAG） techniques, from the hybrids （F1） and newly synthesized allopolyploid generations （S0-$3） between tetraploid cultivated peanut Zhongkaihua 4 with diploid wild one Arachis doigoi. Rapid and considerable gene expression variations began as early as in the FI hybrid or immediately after chromosome doubling. Three types of gene expression changes were observed, including complete silence （gene from progenitors was not expressed in all progenies）, incomplete silence （gene expressed only in some progenies） and new genes activation. Those silent genes mainly involved in RNA transcription, metabolism, disease resistance, signal transduction and unknown functions. The activated genes with known function were almost retroelements by cDNA-SCoT technique and all metabolisms by cDNA-HFO-TAG. These findings indicated that interspecific hybridization and ploidy change affected gene expression via genetic and epigenetic alterations immediately upon allopolyploid formation, and some obtained transcripts derived fragments （TDFs） probably could be used in the research of molecular mechanism of Arachis allopolyploidization which contribute to thwe genetic diploidization of newly formed allopolyploids. Our research is valuable for understanding of peanut evolution and improving the utilization of putative and beneficial genes from the wild peanut.

Transcription-coupled repair pathway in UVC-induced SupF gene mutation in Tet-on 293 cell line

Objective： To explore the role of transcription-coupled repair （TCR） pathway in the UVC-induced SupF gene mutation in Tet-on 293 cell line, we designed and constructed a Tet-responsive plasmid DNA pTCR-C1, and utilized this pTCR-C 1 plasmid to obtain the mutation frequency of SupF reporter gene induced by UVC in Tet-on 293 cell line. Methods： SupF gene was cloned into a Tet-responsive plamid pBI-L, which include a bidirectional Tet-responsive promoter, and was named pTCR-C1. The pTCR-C1 plasmid was transfected into Tet-on 293 cell line, and the mutation frequency of SupF reporter gene was detected in the presence and absence of DOX. Results： The pTCR-C1 plasmid was identified with the methods of restriction digestion and DNA sequencing. The mutation frequency of SupF reporter gene in the presence of DOX was higher than in the absence of DOX. Conclusion： The TCR pathway takes part in the UVC-induced SupF gene mutation in Tet-on 293 cell line.

Genetic screening of 5 blood group systems of Li ethnic group in Hainan province and establishment of rare blood group bank

Objective:To screen the blood group system genes of Duffy,Lutheran,Kidd,Diego,Dombrock blood group systems of Li ethnic group in Hainan Province and provide laboratory data for the rare blood group database in this area.Methods:The alleles of Duffy,Lutheran,Kidd,Diego,Dombrock blood group systems of 300 voluntary participants of Li ethnic group in Hainan were detected by sequence-specific primer polymerase chain reaction,and the polymorphism was analyzed.Results:The allele frequencies of Duffy,Lutheran,Kidd,Diego,Dombrock blood group systems of Li ethnic groups in Hainan Province are 0.9583 for Fy^(a),0.0417 for Fy^(b),0.8350 for Au^(a),0.1650 for Au^(b),0.4500 for Jk^(a),0.5500 for Jk^(b),0.0667 for Di^(a),0.9333 for Di^(b),0.1017 for Doa and 0.8983 for Dob,respectively.The antigen incompatibility rates of Fy^(a)/Fy^(b),Au^(a)/Au^(b),Jk^(a)/Jk^(b),Di^(a)/Di^(b),Doa/Dob of Duffy,Lutheran,Kidd,Diego,Dombrock blood group systems were 7.67%,23.76%,37.25%,11.67%and 16.60%,respectively.Conclusion:The gene frequencies of Duffy,Lutheran,Kidd,Diego,Dombrock blood group systems of Li ethnic group in Hainan Province are polymorphic,and the antigen incompatibility rates of alleles are higher,which is quite different from that of other nationalities in China and with unique ethnic distribution characteristics.It is of great significance to establish the rare blood group database in this region.

Study on the Relationship between 5-HttLPR Gene and BDNF Gene Polymorphism and Post-Traumatic Stress Disorder in Li and Han Nationality of Hainan Province

Objective: To investigate the correlation between 5-HTTLPR (5-and serotonin transporter linked polymer region) gene polymorphism and BDNF (brain derived neural factor) gene polymorphism and PTSD (post traumatic stress disorders) in Li and Han nationalities in Hainan Province. Methods: 167 Hainan Li PTSD patients, 141 Hainan Han PTSD patients and 158 healthy volunteers (control group) were investigated by ETI, caps, Toh, WCST, TMT and WAIS-RC. The polymorphisms of rs6265 locus of 5-HTTLPR and BDNF genes were detected by PCR (polymerase chain reaction) and page (polycylamide gel electrophoresis), and the correlation with PTSD was analyzed. Logistic regression analysis was used to analyze the influencing factors of PTSD. Results: The ETI score, total PTSD score and TMT time of Li PTSD patients were significantly higher than those of Han PTSD patients (P < 0.01). The comprehension, picture filling, picture arrangement, operation IQ and total IQ of WAIS-RC were significantly lower than those of Han PTSD patients (P < 0.01);The numbers of errors, TMT and Toh in WCST were significantly lower than those in Han PTSD patients (P < 0.01). There was no significant difference in the distribution of 5-HTTLPR genotype and allele between Li PTSD patients and control group (P > 0.05). SS genotype of 5-HTTLPR and (GA + AA) genotype of rs6265 locus may increase the risk of PTSD in Hainan Han population. AA and GA + AA genotypes at rs6265 locus may increase the risk of PTSD in Li population (P < 0.05). Among Li PTSD patients, the ETI score, PTSD total score, TMT time, Toh planning time and execution time of AA genotype at rs6265 locus were significantly higher than those of GG genotype;the total scores of comprehension and operation IQ, and Toh in WAIS-RC were significantly lower than those in GG genotype (P < 0.05). Among Han PTSD patients, the ETI score, PTSD total score and TMT time of SS genotype of 5-HTTLPR were significantly higher than those of LL genotype, and the comprehension, arithmetic and block diagram in WAIS-RC were significantly lower than those of LL genotype;The ETI score, PTSD total score and TMT time of patients with (GA + AA) genotype at rs6265 locus were also significantly higher than those of patients with GG genotype. The comprehension and block diagram in WAIS-RC were significantly lower than those of patients with GG genotype. The number of WCST errors in patients with AA genotype was significantly higher than those of patients with GG genotype, and the operational IQ in WAIS-RC was significantly lower than those of patients with GG genotype (P < 0.05). Conclusion: The LL genotype of 5-HTTLPR and the GG genotype of rs6265 locus are related to PTSD of Li and Han nationalities in Hainan, which are important protective factors for PTSD of Li and Han nationalities in Hainan.

Glutamate decarboxylase 1 gene polymorphisms are associated with respiratory symptoms in panic disorder

BACKGROUND Genetic factors play an important role in the pathogenesis of panic disorder(PD).However,the effect of genetic variants on PD remains controversial.AIM To evaluate the associations between glutamate decarboxylase 1(GAD1)gene polymorphisms and PD risk and assess the effect of GAD1 gene polymorphisms on the severity of clinical symptoms in PD.METHODS We recruited 230 PD patients and 224 healthy controls in this study.All participants were assessed for anxiety and panic symptom severity using the Hamilton Anxiety Rating Scale(HAM-A)and Panic Disorder Severity Scale(PDSS).GAD1 gene polymorphisms(rs1978340 and rs3749034)were genotyped and assessed for allele frequencies.RESULTS There were no significant differences between cases and controls in the genotype distributions or allele frequencies of GAD1(rs1978340 and rs3749034).In addition,the effect of GAD1(rs1978340 and rs3749034)on PD severity was not significant.However,regarding respiratory symptoms,patients with the GAD1 rs1978340 A/A genotype had significantly higher scores than those with the A/G or G/G genotype.CONCLUSION Here,we showed that the A/A genotype of GAD1 rs1978340 was associated with increased severity of respiratory symptoms in patients with PD.

甘肃省小麦品种(系)矮秆基因检测及分布规律

地方种是小麦育种的重要种质资源,为了解矮秆基因在地方种中的分布,本研究检测了甘肃省地方种矮秆基因等位变异类型及其在不同麦区的分布频率。结果表明:(1)地方种Rht-B1b和Rht-D1b的频率极低;41.4%的地方种携带Rht8,且春麦区高于冬麦区;46.7%的地方种含Rht24b,春麦区低于冬麦区。Ppd-D1a的频率仅17.8%,且春麦区低于冬麦区。另外,仅检测到Rht-D1b/Rht8、Rht-D1b/Rht24b和Rht8/Rht24b 3种组合,频率分别为0.2%、0.5%和12.8%。(2)地方种携带的矮秆基因及其组合分布频率低于育成种,且差异较大。不同来源育成品种携带的优势矮秆等位变异和频率不同,清水试验站的品种以Rht-D1b、Rht8和Rht24b为主,黄羊试验站的品种以Rht-B1b、Rht-D1b、Rht8和Rht24b为主,甘谷试验站的品种以Rht8和Rht24b为主。清水和黄羊试验站的品种秆矮、丰产性好,可在河西、沿黄灌区、陇南、陇东的小麦育种中应用;甘谷试验站的品种茎秆高,抗病性突出,可应用于定西、天水、陇南和陇东等旱地小麦的抗病改良。(3)基于分子标记检测结果,筛选出15份地方种和31份育成种,以上材料均携带2个及以上降秆基因(包括矮秆基因或Ppd-D1a),可为甘肃不同麦区小麦矮秆育种提供亲本材料。

2021年广西稻瘟病菌致病性分化及其无毒基因分析

【目的】探究广西稻瘟病菌的致病力、优势种群和优势生理小种,分析其无毒基因,了解其生理小种及无毒基因组成与分布情况,为水稻抗性育种和品种推广提供参考。【方法】使用7个我国统一鉴别品种和26份已知抗病基因的近等基因系,采用室内苗期人工喷雾接种方法对2021年从广西南部(桂南)、中部(桂中)、北部(桂北)和高寒山区4个不同生态稻作区分离得到的128株稻瘟病单孢菌株进行致病性测定。【结果】60.16%供试稻瘟病菌菌株表现出强致病力,128株稻瘟病菌株被划分为7个种群26个生理小种,ZB群为优势种群,出现频率为69.53%,优势生理小种为ZB_(13)和ZB_9,出现频率分别为25.00%、14.84%。供试菌株对26个抗病基因的毒力频率为28.12%~100.00%,其中,供试病菌对Pik、Pikm、Pi1、Pi9基因的毒力频率较低,分别为28.12%、28.91%、35.94%、37.50%。供试的广西稻瘟病菌含有与测试抗病基因相对应的无毒基因,其中15个无毒基因在桂南、桂中、桂北和高寒山区4个不同稻作区均有分布,无毒基因Avr-Pia(1)、Avr-Pia(2)、Avr-Pii、Avr-Pik^(s)、Avr-Pib、Avr-Pit、Avr-Pish(2)、Avr-Pi3(t)、Avr-Pi5(t)、Avr-Pi12(t)、Avr-Pi19(t)出现频率均低于20.00%。携带有5、6、7、8、10个无毒基因组合的菌株较多,其在供试菌株中占比分别为19.53%、11.72%、11.72%、15.63%、10.16%。【结论】2021年广西稻瘟病菌致病力强,优势种群为ZB群,优势生理小种为ZB_(13)和ZB_9,无毒基因Avr-Pia(1)、Avr-Pia(2)、Avr-Pii、Avr-Pik^(s)、Avr-Pib、Avr-Pit、Avr-Pish(2)、Avr-Pi3(t)、Avr-Pi5(t)、Avr-Pi12(t)和Avr-Pi19(t)出现频率较低,在水稻抗病育种与品种布局中,与之对应的抗病基因应慎用。

不同SNP等位基因初始频率下家畜保种群体的基因组遗传多样性

【目的】揭示不同SNP等位基因初始频率下家畜保种群体的基因组遗传多样性。【方法】在假定遗传长度为100 cM的1对常染色体上存在1000个均匀分布的SNP基础上,采用Monte Carlo方法模拟在1个规模恒定的闭锁群体内通过随机留种、随机交配连续繁育50个世代的情形,分析3种SNP等位基因初始频率(0.1、0.3、0.5)下各世代最小等位基因频率(minor allele frequency,MAF)及其分布、基因组杂合度(genomic heterozygosity,H_(G))、基因组观察纯合度(genomic observed homozygosity,HOM_(obs))和等位基因丢失数量的变化情况。【结果】无论初始频率如何,随着繁育世代的递增,群体内各SNP的平均MAF和H_(G)持续降低,而HOM_(obs)逐渐升高,MAF位于[0,0.1]区间内的SNP数量以及等位基因丢失数不断增加。相较于较低的初始频率,当SNP等位基因初始频率为0.5时,同一世代的平均MAF和H_(G)最高,HOM_(obs)最低,MAF位于[0,0.1]区间内的SNP数量和等位基因丢失数最少。【结论】SNP等位基因初始频率过低或过高均会导致群体H_(G)降低,并增加基因丢失或固定的概率;而当初始频率接近0.5时,能够有效地维持较高的H_(G),降低基因丢失或固定的风险,从而有利于维持群体遗传多样性。

贵阳地区血小板捐献者HPA-1~6/10/15/21和HLA-A/B基因多态性研究

目的研究贵阳地区机采血小板捐献者人类血小板抗原HPA-1~6/10/15/21及人类白细胞抗原HLA-A、B基因分布及多态性。方法采用实时荧光定量PCR法(qPCR)对287名贵阳地区机采血小板捐献者进行HPA-1~6/10/15/21和HLA-A、B基因分型,列举aa\ab\bb基因及HLA-A、B等位基因的分布情况、计算aa\ab\bb基因及HLA-A、B等位基因型频率。结果287名血小板捐献者HPA-1~6/10/15/21系统中,HPA-4和HPA-10的基因型均为aa型,不具有多态性;HPA-1,2,5,6和21主要以aa型为主;仅在HPA-3和HPA-15中检出bb型;杂合度最高的是HPA-15,HPA3杂合度居次;HLA-A位点检出14个等位基因,频率最高的3个是A*02(0.36)、A*11(0.33)和A*24(0.162;HLA-B位点检出23个等位基因,频率最高的4个是B*46(0.19)、B*15(0.149、B*40(0.14)和B*13(0.13)。结论贵阳地区机采血小板捐献者HPA-1~6/10/15/21和HLA-A、B基因存在多态性,需建立该地HPA/HLA基因分型血小板供者库服务于临床。