Specific HLA-DQB1 alleles associated with risk for development of hepatocellular carcinoma:A meta-analysis

AIM:To evaluate the association of human leukocyte antigen(HLA)-DQB1 alleles with hepatocellular carcinoma(HCC) through meta-analysis of published data.METHODS:Case-control studies on HLA-DQB1 allele association with HCC published up to January 2010 were included in the analyses.The odds ratios(ORs) of HLADQB1 allele distributions in HCC patients were analyzed and compared with healthy controls.The meta-analysis software REVMAN 5.0 was applied for investigating heterogeneity among individual studies and for summarizing all the studies.A meta-analysis was performed using fixed-effect or random-effect methods,depending on the absence or presence of significant heterogeneity.Seven case-control studies containing 398 cases and 594 controls were included in the final analysis.RESULTS:Among the five family alleles,two(DQB1*02 and DQB1*03) were found to be significantly associated with the risk of HCC.The combined OR for the association of DQB1*02 and DQB1*03 allele with the risk for HCC was 1.78(95% CI:1.05-3.03,P = 0.03) and 0.65(95% CI:0.48-0.89,P = 0.007),respectively.Among the 13 specific alleles,two(DQB1*0502 and DQB1*0602) were significantly associated with risk of HCC.The combined OR for the association of DQB1*0502 and DQB1*0602 allele with the risk for HCC was 1.82(95% CI:1.14-2.92,P = 0.01) and 0.58(95% CI:0.36-0.95,P = 0.03),respectively.No significant association was established for other HLA-DQB1 family alleles and specific alleles.CONCLUSION:Our results support the hypothesis that specific HLA-DQB1 allele families and alleles might influence the susceptibility or resistance to HCC,although it needs further investigations.

Characterization and distribution of novel alleles of the vernalization gene Vrn-A1 in Chinese wheat(Triticum aestivum L.) cultivars

The ability of wheat to adapt to a wide range of environmental conditions is determined mostly by allelic diversity among genes regulating vernalization requirement.Vrn-1 is a major regulator of this requirement.In this study,two novel alleles of Vrn-A1 were discovered in Chinese cultivars:vrn-A1n was identified in two landraces,Jiunong 2 and Ganchun 16,and Vrn-A1o was detected in Duanhongmangmai.Both novel alleles showed a linked duplication in the promoter region.The common copy of these two alleles was identical to the recessive allele vrn-A1.Compared with the recessive allele vrn-A1,the other copy of vrn-A1n contained a 54-bp deletion in the promoter region and the distinct copy of Vrn-A1o contained an11-bp deletion in the promoter region.In segregating populations in the greenhouse under nonvernalizing(20–25°C)and long-day(16 h light)conditions,plants with the novel vrn-A1n allele did not head earlier than those with the recessive vrn-A1 allele.However,plants that were either homozygous or heterozygous for the novel Vrn-A1o allele headed earlier than those with the recessive vrn-A1 allele.To identify the novel allele with the small-sized product and facilitate screening,a DNA marker for the novel dominant allele Vrn-A1o was designed.Analysis of the novel-allele distribution showed that two cultivars carrying the vrn-A1n allele were dispersed in the northwestern spring wheat zone,and 12 cultivars carrying the dominant Vrn-A1o allele were widely distributed in the northwestern spring wheat zone,Xinjiang winter and spring wheat zone,Yellow and Huai River valley winter wheat zone,and QinghaiTibetan Plateau spring and winter wheat zone.Our study identifies useful germplasm and a DNA marker for wheat breeding.

An allelic variation in the promoter of the LRR-RLK gene,qSS6.1,is associated with melon seed size

Seed size is an important agronomic trait in melons that directly affects seed germination and subsequent seedling growth.However,the genetic mechanism underlying seed size in melon remains unclear.In the present study,we employed Bulked-Segregant Analysis sequencing(BSA-seq)to identify a candidate region(~1.35 Mb)on chromosome 6 that corresponds to seed size.This interval was confirmed by QTL mapping of three seed size-related traits from an F2 population across three environments.This mapping region represented nine QTLs that shared an overlapping region on chromosome 6,collectively referred to as qSS6.1.New InDel markers were developed in the qSS6.1 region,narrowing it down to a 68.35 kb interval that contains eight annotated genes.Sequence variation analysis of the eight genes identified a SNP with a C to T transition mutation in the promoter region of MELO3C014002,a leucine-rich repeat receptor-like kinase(LRR-RLK)gene.This mutation affected the promoter activity of the MELO3C014002 gene and was successfully used to differentiate the large-seeded accessions(C-allele)from the small-seeded accessions(T-allele).qRT-PCR revealed differential expression of MELO3C014002 between the two parental lines.Its predicted protein has typical LRR-RLK family domains,and phylogenetic analyses reveled its similarity with the homologs in several plant species.Altogether,these findings suggest MELO3C014002 as the most likely candidate gene involved in melon seed size regulation.Our results will be helpful for better understanding the genetic mechanism regulating seed size in melons and for genetically improving this important trait through molecular breeding pathways.

Genetic Diversity of Gli-1, Gli-2 and Glu-1 Alleles in Sichuan Wheat Landraces

Genetic diversity at Gli_1, Gli_2 and Glu_1 loci was investigated in 89 Sichuan wheat (Triticum aestivum L.) landraces by using acid polyacrylamide gel electrophoresis (APAGE) and SDS_PAGE. In these landraces, a total of 32 gliadin and 3 high_molecular_weight (HMW) glutenin patterns were observed. In total, 14, 15 and 5 alleles were identified at Gli_1, Gli_2 and Glu_1, respectively. At each locus, the alleles in higher frequency were Gli_A1a (89%), Gli_B1h (46%), Gli_D1a (65%), Gli_A2a (64%), Gli_B2j (45%), Gli_D2a (48%), Glu_A1c (99%), Glu_B1b (99%) and Glu_D1a (100%). The Nei's genetic variation index (H) of Sichuan wheat landraces was 0.370?6, varying from 0 to 0.708?7. The highest genetic diversity was found at Gli_B2 locus, while the lowest was found at Glu_D1. The genetic diversity at Gli loci was higher than that of Glu_1 loci among these landraces, but it was much lower than that of modern wheat cultivars. These results indicated a narrow genetic base of Sichuan wheat landraces. In this study, “Chengdu_guangtou” had the identical gliadin and HMW_glutenin patterns with “Chinese Spring”, further supporting the proposal that “Chinese Spring” is a strain of “Chengdu_guangtou”.

Genetic Diversity of Gli-1,Gli-2 and Glu-1 Alleles Among Chinese Endemic Wheats

Genetic diversity at Gli_1, Gli_2 and Glu_1 loci was investigated in 32 accessions of Chinese endemic wheat by using acid polyacrylamide gel electrophoresis (APAGE) and sodium dodecyl sulfate (SDS)_PAGE. There were 8 gliadin and 3 high_molecular_weight (HMW)_glutenin patterns in 14 Yunnan hulled wheat ( Triticum aestivum ssp. yunnanese King) accessions, 9 gliadin and 4 HMW_glutenin patterns in 9 Tibetan weedrace ( T. aestivum ssp. tibetanum Shao ) accessions, and 9 gliadin and 5 HMW_glutenin patterns in 9 Xinjiang rice wheat ( T. petropavlovskyi Udacz. et Migusch.) accessions. One accession (i.e. Daomai 2) carried new subunits 2.1+10.1 encoded by Glu_D1. Among the three Chinese endemic wheat groups, a total of 10, 14 and 11 alleles at Gli_1 locus; 11, 14 and 12 alleles at Gli_2 locus; and 5, 6 and 8 alleles at Glu_1 locus were identified, respectively. Among Yunnan hulled wheat, Tibetan weedrace and Xinjiang rice wheat, the Nei's genetic variation indexes were 0.3798, 0.5625 and 0.5693, respectively. These results suggested that Tibetan weedrace and Xinjiang rice wheat had higher genetic diversity than Yunnan hulled wheat.

Characterization of Genetic Polymorphism of Novel MHC B-LBⅡ Alleles in Chinese Indigenous Chickens

Genetic polymorphism of the major histocompatibility complex （MHC） B-LBⅡ gene was studied by amplification of exon 2 using PCR, followed by cloning and DNA sequencing in eight indigenous Chinese chicken populations. To reveal the genetic variation of the B-LB Ⅱ gene, 37 types of patterns detected by PCR-SSCP were investigated first, which would be used to screen novel B-LB Ⅱsequences within the breeds. The types of PCR-SSCP patterns and final sequencing allowed for the identification of 31 novel MHC B-LBⅡ alleles from 30 unrelated individuals of Chinese chickens that were sampled. These are the first designators for the alleles of chicken MHC B-LBⅡ gene based on the rule of assignment for novel mammalian alleles. Sequence alignment of the 31 B-LB Ⅱ alleles revealed a total of 68 variable sites in the fragment of exon 2, of which 51 parsimony informative and 17 singleton variable sites were observed. Among the polymorphic sites, the nucleotide substitutions in the first and second positions of the codons accounted for 36.76% and 35.29%, respectively. The sequence similarities between the alleles were estimated to be 90.6%-99.5%. The relative frequencies of synonymous and nonsynonymous nucleotide substitutions within the region were 2.92%±0.94% and 14.64%±2.67%, respectively. These results indicated that the genetic variation within exon 2 appeared to have largely arisen by gene recombination and balancing selection. Alignment of the deduced amino acid sequences of the β1 domain coded by exon 2 revealed 6 synonymous mutations and 27 nonsynonymous substitutions at the 33 disparate sites. In particular, the nonsynonymous substitutions at the putative peptide-binding sites are considered to be associated with immunological specificity of MHC B-LB Ⅱ molecule in Chinese native chickens. These results can provide a molecular biological basis for the study of disease resistance in chicken breeding.

A Recursive Algorithm for Offspring's Genotype Frequency of Selfing Population on Multiple Alleles with Limited Loci

This paper studies the offspring＇s genotype frequency of the selfing population on multiple alleles with limited loci.A recursive algorithm is given for it.It is discovered that the genotype frequency of homozygous gene of limited loci increases by generations.Relative increment reduces by generations and the genotype frequency tends to a definite value finally.The genotype frequency of limited loci with hybrid gene tends to 0 finally.But it is possibility that the genotype frequency increases in previous generations then reduces later.It is found that the number of the hybrid gene are more,the speeds tending to 0 are quicker.

中国北方汉族人群HLA-DQA1、-DQB1和HLA-DPA1、-DPB1等位基因多态性分析

目的 调查中国北方汉族人群HLA-DQA1、-DQB1、 HLA-DPA1、-DPB1等位基因多态性。方法 选取2016年中华骨髓库造血干细胞志愿者1 004人的外周血样,采用第2代测序方法(next generation sequence,NGS)进行HLA-DQA1、-DQB1、HLA-DPA1、-DPB1等位基因分型。结果 1 004人份样本中,共检出24种HLA-DQA1、20种HLADQB1、12种HLA-DPA1、40种HLA-DPB1等位基因。各位点频率较高的前3种等位基因依次为HLA-DQA1^(*)01:02:01(15.2%),HLA-DQA1^(*)03:02:01(15.2%),HLA-DQA1^(*)05:05:01(8.0%);HLA-DQB1^(*)03:01:01 (19.0%),HLA-DQB1^(*)03:03:02(16.2%),HLA-DQB1^(*)05:02:01(11.2%);HLA-DPA1^(*)02:02:02(52.2%),HLA-DPA1^(*)01:03:01(33.0%),HLA-DPA1^(*)02:01:01(10.3%);HLA-DPB1^(*)05:01:01(37.0%),HLA-DPB1^(*)02:01:02(17.6%),HLA-DPB1^(*)04:01:01(10.0%)。HLA-DQA1、-DQB1和HLA-DPA1、-DPB1之间的单体型存在连锁不平衡。结论 获得北方汉族人群HLADQA1、-DQB1和HLA-DPA1、-DPB1等位基因多态性数据和单体型数据,可为器官移植、群体遗传学和疾病关联研究等提供重要参考数据。

Association of HLA-B Alleles With Human Immunodeficiency Virus Type 1 Infection in the Yi Ethnic Group in Sichuan Province

Objective To determine the distribution of HLA-B alleles in the Chinese Yi ethnic group and its association with HIV infection. Methods One hundred and six unrelated healthy HIV negative and 73 HIV positive Chinese Yi ethnic individuals were typed by PCR-SSP. Results The frequency of alleles B*07, B*35, and B*46 were increased in HTV-1 -positive subjects, whereas the alleles B*55, B*44 and B*78 were absent in the HIV-infected persons studied. The B*46 allele was present in a significantly higher gene frequency among HIV-1-positive individuals (P=0.02, OR=3.32, 95% CI=1.13-9.78) compared with control subjects. Conclusion HLA-B*46 may be associated with its susceptibility to HIV-1 infections.

Identification of Multiple Alleles at the Wx Locus and Development of Single Segment Substitution Lines for the Alleles in Rice

The microsatellite markers 484/485 and 484/W2R were used to identify the multiple alleles at the Wx locus in rice germplasm. Fifteen alleles were identified in 278 accessions by using microsatellite class and G-T polymorphism. Among these alleles, （CT）12-G, （CT）15-G, （CT）16-G, （CT）17-G, （CT）18-G and （CT）21-G have not been reported. Seventy-two single-segment substitution lines （SSSLs） carrying different alleles at the Wx locus were developed by using Huajingxian 74 with the （CT）11-G allele as a recipient and 20 accessions containing 12 different alleles at the Wx locus as donors. The estimated length of the substituted segments ranged from 2.2 to 77.3 cM with an average of 17.4 cM.

Genome-wide association study identifies favorable SNP alleles and candidate genes for waterlogging tolerance in chrysanthemums

Chrysanthemums are sensitive to waterlogging stress,and the development of screening methods for tolerant germplasms or genes and the breeding of tolerant new varieties are of great importance in chrysanthemum breeding.To understand the genetic basis of waterlogging tolerance(WT)in chrysanthemums,we performed a genome-wide association study(GWAS)using 92,811 single nucleotide polymorphisms(SNPs)in a panel of 88 chrysanthemum accessions,including 64 spray cut and 24 disbud chrysanthemums.The results showed that the average MFVW(membership function value of waterlogging)of the disbud type(0.65)was significantly higher than that of the spray type(0.55)at P<0.05,and the MFVW of the Asian accessions(0.65)was significantly higher than that of the European accessions(0.48)at P<0.01.The GWAS performed using the general linear model(GLM)and mixed linear model(MLM)identified 137 and 14 SNP loci related to WT,respectively,and 11 associations were commonly predicted.By calculating the phenotypic effect values for 11 common SNP loci,six highly favorable SNP alleles that explained 12.85—21.85%of the phenotypic variations were identified.Furthermore,the dosage-pyramiding effects of the favorable alleles and the significant linear correlations between the numbers of highly favorable alleles and phenotypic values were identified(r2=0.45;P<0.01).A major SNP locus(Marker6619-75)was converted into a derived cleaved amplified polymorphic sequence(dCAPS)marker that cosegregated with WT with an average efficiency of 78.9%.Finally,four putative candidate genes in the WT were identified via quantitative real-time PCR(qRT-PCR).The results presented in this study provide insights for further research on WT mechanisms and the application of molecular marker-assisted selection(MAS)in chrysanthemum WT breeding programs.

The distribution of HLA-A,-B,and-DRB1 alleles and haplotypes in inhabitants of Guizhou Province of China

The present study was aimed to analyze the frequencies of human leukocyte antigen （HLA）-A, -B, and -DRB1 alleles and A-B-DRBI, A-B, A-DRB1 and B-DRB1 haplotypes in inhabitants of Guizhou province, China. All samples were typed in the HLA-A,-B, and -DRB1 loci using the polymerase chain reaction-reverse sequence spe- cific oligonucleotide probe （PCR-rSSOP） method and HLA polymorphisms were analyzed. A total of 18 HLA-A, 31 HLA-B, and 13 HLA-DRB1 alleles were found in the Guizhou population. The first two frequent alleles in the HLA-A, -B, and -DRB1 loci were A＊1 1（30.72%） and A＊02（30.65%）, B＊40（16.27%） and B＊46（16.27%）, and DRBl＊09（15.91%） and DRBl＊15（13.51%）, respectively. The most common haplotype was A＊02-B＊46- DRBl＊09（5.59%） in A-B-DRB1, A＊02-B＊46（I 1.73%） in A-B, B＊46-DRBl＊09（7.49%） in B-DRB1, and A＊02- DRBl＊09（8.08%） in A-DRB1. Some baplotypes with strong linkage disequilibrium （LD） were found not only in the common haplotypes, such as A＊33-B＊58, B＊30-DRB1＊07, and B＊33-DRB1＊03, but also in the rare haplotypes, such as A＊01-B＊37, B＊37-DRB1＊10, and A＊01-DRB1＊10. Guizhou inhabitants shared some characteristics of the Southern Chinese population but also had their own unique features. Overall, HLA polymorphism in Guizhou population was more consistent with that of Chengdu population than that of other populations in China.

Determination of the Number of SSR Alleles Necessary for the Analysis of Genetic Relationships Between Maize Inbred Lines

The amount of molecular marker information has considerable impact on the results of studies of crop germplasm genetic relationships in crop. The number of alleles required to reveal genetic relationship in maize inbred lines is a theoretical issue that needs to be addressed. In this study, 112 pairs of SSR （simple sequence repeat） primers and 97 maize inbred lines were selected to study the relationship between the number of inbred lines and the number of SSR primers and alleles required for a stable cluster. The results showed that the number of SSR primers is not tightly associated with the stability of the cluster analysis results, while an increase in the number of alleles can significantly improve the stability of cluster analysis results. The number of inbred lines （X） is significantly associated with the number of alleles required for stable cluster analysis （Y）, and the regression equation is Y- 600.8xe（-15.9/x）. This equation can be used to calculate the number of SSR alleles required for a genetic relationship study of maize inbred lines. These results provide a reference for determining of SSR alleles number in genetic relationship analysis of maize inbred line and other crop germplasm.

HLA class Ⅱ alleles and risk for peripheral neuropathy in type 2 diabetes patients

The potential impact of human leukocyte antigen （HLA） genotype variations on development of diabetic peripheral neuropathy （DPN） is not well determined. This study aimed to identify the association of HLA class II alleles with DPN in type 2 diabetes （T2D） patients. Totally 106 T2D patients, 49 with DPN and 57 without DPN, and 100 ethnic-matched healthy controls were analyzed. Both groups of the patients were matched based on sex, age, body mass index （BMI） and duration of T2D. Polyneuropathy was diagnosed using electrodiagnostic methods. HLA-DRB1 and DQB1 genotyping was performed in all subjects by the polymerase chain reaction with sequence-specific primers （PCR-SSP） method. T2D patients with DPN showed higher frequencies of HLA-DRB1＊10 and DRB1＊12 alleles compared to control group （P = 0.04）. HLA-DQB1＊02 allele and HLA-DRB1＊07-DQB1＊02 haplotype were associated with a decreased risk for developing DPN in T2D patients （P = 0.02 and P = 0.05 respectively）. Also, patients with severe neuropathy showed higher frequencies of DRB1＊07 （P = 0.003） and DQB1＊02 （P = 0.02） alleles than those with mild-to-moderate form of neuropathy. The distribution of DRB 1 and DQB 1 alleles and haplotypes were not statistically different between all patients and healthy controls. Our findings implicate a possible protective role of HLA-DQB1＊02 allele and HLA-DRB1＊07-DQB1＊02 haplotype against development of peripheral neuropathy in T2D patients. Therefore, variations in HLA genotypes might be used as genetic markers for prediction and potentially management of neuropathy in T2D patients.

Self-compatibility in peach[Prunus persica(L.)Batsch]:patterns of diversity surrounding the S-locus and analysis of SFB alleles

Self-incompatibility(SI)to self-compatibility(SC)transition is one of the most frequent and prevalent evolutionary shifts in flowering plants.Prunus L.(Rosaceae)is a genus of over 200 species most of which exhibit a Gametophytic SI system.Peach[Prunus persica(L.)Batsch;2n=16]is one of the few exceptions in the genus known to be a fully selfcompatible species.However,the evolutionary process of the complete and irreversible loss of SI in peach is not well understood and,in order to fill that gap,in this study 24 peach accessions were analyzed.Pollen tube growth was controlled in self-pollinated flowers to verify their self-compatible phenotypes.The linkage disequilibrium association between alleles at the S-locus and linked markers at the end of the sixth linkage group was not significant(P>0.05),except with the closest markers suggesting the absence of a signature of negative frequency dependent selection at the S-locus.Analysis of SFB1 and SFB2 protein sequences allowed identifying the absence of some variable and hypervariable domains and the presence of additionalα-helices at the C-termini.Molecular and evolutionary analysis of SFB nucleotide sequences showed a signature of purifying selection in SFB2,while the SFB1 seemed to evolve neutrally.Thus,our results show that the SFB2 allele diversified after P.persica and P.dulcis(almond)divergence,a period which is characterized by an important bottleneck,while SFB1 diversified at a transition time between the bottleneck and population expansion.

Influence of HLA-DRB1 alleles and HBV genotypes on interferon-α therapy for chronic hepatitis B

AIM. To investigate the influence of HLA-DRB1 alleles and HBV genotypes on inberferon-α therapy for chronic hepatitis B. METHODS： HLA-DRBI＊03, ＊07, ＊09,＊12, ＊15 alleles were determined using polymerase chain reaction/sequence specific primer （PCR/SSP） technique in 126 patients with chronic hepatitis B and 76 normal control subjects in Shandong Province, and HBV genotypes were determined by nested-PCR analysis using type-specific primers in 126 patients. RESULTS： The positivity of HLA-DRB1＊07 allele in chronic hepatitis B group was significantly higher than that in normal control group （X^2 = 6.33, P〈0.025, RR = 2.37）. Among the 126 patients, genotype B was found in 38 （30.2%）, genotype C in 69 （54.8%）, and mixed genotype （B＋C） in 19 （15.0%）, genotypes D-F were not found. Among the 46 DRB1＊07（＋） patients, 7 were responders and 39 were non-responders among them （X^2 = 6.71, P〈0.05）. The positivity of HLADRB1＊07 and prevalence of HBV genotype C were significantly higher in non-responders than in responders. CONCLUSION： High positivities of HLA-DRB1 ＊07 allele and HBV genotype C are closely associated with the lower response to interferon-α therapy for chronic hepatitis B.

Differential expressions among five Waxy alleles and their effects on the eating and cooking qualities in specialty rice cultivars

Eating and cooking qualities（ECQs） of rice are important attributes due to its major influence on consumer acceptability. To better understand the molecular mechanism of the variation in ECQs, we investigated and compared the expressions among different alleles of the Waxy（Wx） gene and its effect on ECQs in specialty rice cultivars. The results showed that the accumulation of amylose was positively and significantly correlated to the level of mature Wx m RNA and granule-bound starch synthase I（GBSS I） in developing rice grain at 12 days after flowering. The amount of GBSS I and its activity together are the main factors controlling amylose synthesis. Differences in ECQs among five Wx allele types were investigated in samples from 15 rice varieties. The apparent amylose content（AAC） and gel consistency（GC） were similar in each type of Wx allele. The AAC followed the order, Wx^a type〉Wx^in type〉Wx^b type〉Wx^mq type〉wx. Contrary to this, the GC showed an opposite trend compared to AAC. There was a wide variation in rapid visco analyzer（RVA） profile among five Wx allele types, while varieties sharing a specified Wx allele had basically the similar RVA profile, although there was a slight difference in some RVA parameters, peak, hot paste and cool paste viscosities.

Expression Analysis of Restorer Alleles-Induced Genes in Pepper

Fertility restoration of cytoplasmic male-sterility in pepper （Capsicum annuum L.） is useful for commercial production of hybrid seeds. However, the mechanism of fertility restoration has not been determined. We previously constructed a cDNA library and identified some genes related to fertility restoration in pepper using suppression subtractive hybridization technology. In this study, the expression patterns of 20 genes were investigated using semi-quantitative RT-PCR. Three genes expressed only in restorer lines, but not in sterility lines. Four genes expressed only in anther, but not in other organs. Among these 7 genes, the clone TG31 was observed to specifically express in anther of restorer lines. The work described here provides a comprehensive overview on the expression pattern of the genes that are induced by restorer alleles in pepper. It will also contribute to the current understanding of molecular networks for the regulation of fertility restoration.

Human leukocyte antigen class-Ⅱ DRB1 alleles and Giardia lamblia infection in children: A case-control study

Objective:To compare the genotype frequencies of HLA class-ⅡDRB1 alleles in Giardia(G.)lamblia-infected children.Methods:A total of 490 Egyptian children aged 2-16 years were subjected to microscopic stool examination to detect G.lamblia infection,and to exclude other intestinal pathogens.On the basis of their microscopic findings,a group of 80 children were chosen as giardiasis cases,another 80 children were confirmed as Giardia free control group by immunochromatographic test,and the remaining children were excluded.Both giardiasis and control groups were then subjected to blood examination to identify their genetic type of HLA-DRB1 alleles.Results:HLA class-ⅡDRB1*03:01 and DRB1*13:01 alleles were significantly associated with G.lamblia infection(P<0.001 for each variable).On the other hand,HLA class-ⅡDRB1*04:02,DRB1*10:01,DRB1*14:01 and DRB1*15:01 alleles were significantly demonstrated in Giardia free children.However,other HLA-DRB1 alleles did not show any significant association with giardiasis.Conclusions:HLA class-ⅡDRB1*03,DRB1*13,DRB1*04,DRB1*10,DRB1*14 and DRB1*15 alleles may be involved in the establishment of host immune response to G.lamblia infection.

Molecular characteristics of S-RNase alleles as the determ inant of self-i ncompatibility in the style of Fragaria viridi

Strawberry(Fragaria spp.)is a member of the Rosoideae subfamily in the family Rosaceae.The self-incompatibility(SI)of some diploid species is a key agronomic trait that acts as a basic pollination barrier;however,the genetic mechanism underlying SI control in strawberry remains unclear.Two candidate S-RNases(S a-and S^-RNase)identi fi ed in the transcriptome of the styles of the self-incompatible Fragaria viridis 42 were con fi rmed to be SI determinants at the S locus following genotype identi fi cation and intraspeci fi c hybridization using sel fi ng progenies.Whole-genome collinearity and RNase T2 family analysis revealed that only an S locus exists in Fragaria;however,none of the compatible species contained S-RNase.Although the results of interspeci fi c hybridization experiments showed that F.viridis(SI)styles could accept pollen from F.mandshurica(self-compatible),the reciprocal cross was incompatible.S a and S b-RNase contain large introns,and their noncoding sequences(promotors and introns)can be transcribed into long noncoding RNAs(lncRNAs).Overall,the genus Fragaria exhibits S-RNase-based gametophytic SI,and S-RNase loss occurs at the S locus of compatible germplasms.In addition,a type of SI-independent unilateral incompatibility exists between compatible and incompatible Fragaria species.Furthermore,the large introns and neighboring lncRNAs in S-RNase in Fragaria could offer clues about S-RNase expression strategies.