The application of sequence specific primer and RT-PCR to LRRK2 gene polymorphism typing

Objective:To establish a new detecting method for disease susceptibility loci R1628P and G2385R of Parkinson’s disease(PD)related gene LRRK2.Methods:Sequence specific primers were designed to make a genotyping of DNA markers with known genotypes by use of quantitative fluorescence real-time PCR(RT-PCR).100 cases of PD samples with unknown genotypes were tested,and verified by use of polymerase chain reaction linked restriction fragment length polymorphism(PCR-RLFP).Results:The genotyping results of DNA markers proved to be correct,and 100 cases of samples to be tested had a completely consistent genotyping result with PCR-RLFP genotyping result.Conclusions:Sequence specific primer and quantitative fluorescence RT-PCR can successfully make a genotyping for disease susceptibility loci R1628P and G2385R of LRRK2.

Analysis on 16S-ITS Marker from Bacillus licheniformis and Its Specificity

[Objective] This study aimed to establish molecular identification methods for Bacillus licheniformis. [Method] Based on clone sequencing and difference analysis for 16S and ITS sequences of B. licheniformis TS-01, specific primers were designed using region sequences as the targets used for amplifying all test strains. [Result] The specific primers of B. licheniformis were designed from the ITS and 16S rDNA regions. The optimal annealing temperature of the specific primers for PCR was 67.2 ℃ with 24 cycles. A 905 bp marker fragment was amplified for B. licheniformis TS-01, while all other test strains showed negative results. This indicated that a specific 16S-ITS marker was obtained, which accurately identified the strain at the species level. [Conclusion] This molecular identification method for B. licheniformis TS-01 has laid the foundation for molecular diagnosis of B. licheniformis.

A study on the pathogen species and physiological races of tomato Fusarium wilt in Shanxi,China

In order to clarify the main pathogens of tomato Fusarium wilt in Shanxi Province, China, morphological identification, elongation factor 1 alpha （EF-1α） sequence analysis, specific primer amplification and pathogenicity tests were applied to study the isolates which were recovered from diseased plants collected from 17 different districts of Shanxi Province. The results were as follows： 1） Through morphological and molecular identification, the following 7 species of Fusarium were identified： F. oxysporum, F. solani, F. verticillioides, F. subglutinans, F. chlamydosporum, F. sporotrichioides, and F. semitectum; 2） 56 isolates of F. oxysporum were identified using specific primer amplification, among which, 29, 5 and 6 isolates were respectively identified as F. oxysporum f. sp. lycopersici physiological race 1, race 2, and race 3; 3） pathogenicity test indicated the significant pathogenicity of F. oxysporum, F. solani, F. verticillioides, and F. subglutinans to tomato plant. Therefore, among these 4 species confirmed as pathogenic to tomato in Shanxi, the highest isolation rate （53.3％） corresponded to F. oxysporum. Three physiological species, race 1, race 2, and race 3 of F. oxysporum f. sp. lycopersici are detected in Shanxi, among which race 1 is the most widespread pathogen and is also considered as the predominant race.

Association of HLA-DRB1, DQB1 Alleles with Chronic Urticaria

In order to investigate the association of genotypes of HLA-DRB1 and HLA-DQB1 alleles with the genetic susceptibility of chronic urticaria (CU), genotypes of HLA-DRB1 and HLA-DQB1 genes were detected by polymerase chain reactions with sequence-specific primers (PCR-SSP) in 42 patients with CU (19 men and 23 women, mean age 30.67±12.45 y old as well as 193 racially matched healthy persons in ethnic Han from Hubei provinece. Gene frequencies of HLA-DRB1*12, *0901 (RR=3.11, χ2=7.579, P=0.006; RR=2.47, χ2=5.684, P=0.017) were significantly increased in CU patients as compared with that in healthy people. Gene frequencies of HLA-DQB1*05 (RR=0.26, χ2=6.683, P=0.01) were significantly decreased in CU patients. It was suggested that CU was found strongly associated with HLA-DRB1*12, *0901 and HLA-DQB1*05, the former might be the genetic markers for susceptibility to CU, but the latter might play a resistive role.

Genetic Diversity of Fusarium solani f. sp. cucurbitae, the Causal Root and Crown Rot of Cucurbits (Melon) by Using Molecular Markers and Control

Detection of F. solani f. sp. cucurbitae causal agent of the crown and root rot disease of melon race 1, race 2 is difficult. It is based only on morphological characteristic. In this study, forty isolates identified as Fusarium solani based on morphological characterization, F. solani was one of the most frequently isolated species. Molecular identification of these isolates by PCR technique using species-specific primer, indicated that thirty-two isolates, amplified product 580 bp (race 1) and two isolate amplified product 580 bp (race 2), while six isolates were not amplified with primer of both races. Production of Trichothecenes (T2-toxen, DON.) by Fusarium solani was conducted on isolates confirmed as belonging in the F. solani by PCR. The results indicated that the presence of Tri5, Tri13 genes is coding the ability of synthesis mycotoxin. In vitro, the results indicated that NPs (AgNPs, MgNPs) and chemical (Phylex) possess the antifungal properties against at various level. Treatment with (AgNPs 150 ppm, MgNPs 2%, 3% ppm) and 3% Phylex resulted in maximum inhabitation of F. solani . In vivo, five characters (height plant, hoot ant root fresh and dry weight) were measured based on the greenhouse, field experimental results. Treatment with (AgNPs, MgNPs) and Phylex had higher measured parameters than positive control.

Streamlined whole-genome genotyping through NGS-enhanced thermal asymmetric interlaced(TAIL)-PCR

Whole-genome genotyping(WGG)stands as a pivotal element in genomic-assisted plant breeding.Nevertheless,sequencing-based approaches for WGG continue to be costly,primarily owing to the high expenses associated with library preparation and the laborious protocol.During prior development of foreground and background integrated genotyping by sequencing(FBI-seq),we discovered that any sequence-specific primer(SP)inherently possesses the capability to amplify a massive array of stable and reproducible non-specific PCR products across the genome.Here,we further improved FBI-seq by replacing the adapter ligated by Tn5 transposase with an arbitrary degenerate(AD)primer.The protocol for the enhanced FBI-seq unexpectedly mirrors a simplified thermal asymmetric interlaced(TAIL)-PCR,a technique that is widely used for isolation of flanking sequences.However,the improved TAIL-PCR maximizes the primer-template mismatched annealing capabilities of both SP and AD primers.In addition,leveraging of next-generation sequencing enhances the ability of this technique to assay tens of thousands of genome-wide loci for any species.This cost-effective,user-friendly,and powerful WGG tool,which we have named TAIL-PCR by sequencing(TAIL-peq),holds great potential for widespread application in breeding programs,thereby facilitating genome-assisted crop improvement.

RHD gene polymorphism among RhD-negative Han Chinese

Objective To evaluate the status of eight RHD specific exons in 131 Han Chinese blood donors who were classified as RhD-negative by serological methods and explore the genomic structure of RHD gene among the Han Chinese. The Rh blood group system has the highest prevalence of polymorphisms among human blood group systems and is clinically significant in transfusion medicine. The Rh antigens are expressed on polypeptides encoded by two highly homologous genes,RHD and RHCE. Recent molecular studies have shown that the RhD-negative trait could be generated by multiple genetic mechanisms and is ethnic group-dependent. Methods The polymerase chain reaction using-sequence specific primers (PCR-SSP) was used to amplify exons 2,3,4,5,6,7,9 and 10 of RHD gene and exons 1,2 and 5 of RHCE gene,as well as intron 4 in each of them.Results The 131 cases of RhD-negative phenotypes consisted of 60 ccee,58 Ccee,5 ccEe,5 CcEe and 3 CCee. Among them,83 with the Rh ccee or ccEe phenotypes (63.4%) lacked the eight RHD exons indicated above,while 26 cases with the Rh Ccee,CCee,CcEe phenotypes (19.9%) had all the RHD exons examined. Twenty-two individuals with the Ccee,CCee,CcEe phenotypes (16.8%) carried at least one RHD exon. The phenotypes of the RhD negative individuals carrying the RHD gene were Rh CC or Cc,but not cc. Conclusions Three classes of RhD-negative polymorphisms among a population of Han Chinese were observed. Antigen association analysis suggested the existence of a novel class of RhD-negative associated haplotype in Han Chinese. This haplotype consisted of a normal RHCE allele and a nonfunctional RHD gene. It may be beneficial to redefine the RhD-negative blood group among Chinese populations upon clarification of the mechanisms of RHD gene expression and RhD antigen immunization.