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Objectives: The study evaluated sub-microscopic malaria infections in pregnancy using two malaria Rapid Diagnostic Tests (mRDTs), microscopy and RT-PCR and characterized Plasmodium falciparum dihydrofolate reductase (Pfdhfr) and Plasmodium falciparum dihydropteroate synthase (Pfdhps) drug resistant markers in positive samples. Methods: This was a cross sectional survey of 121 pregnant women. Participants were finger pricked, blood drops were collected for rapid diagnosis with P. falciparum histidine-rich protein 11 rapid diagnostic test kit and the ultra-sensitive Alere Pf malaria RDT, Blood smears for microscopy and dried blood spots on Whatman filter paper for molecular analysis were made. Real time PCR targeting the var acidic terminal sequence (varATS) gene of P. falciparum was carried out on a CFX 96 real time system thermocycler (BioRad) in discriminating malaria infections. For each run, laboratory strain of P. falciparum 3D7 and nuclease free water were used as positive and negative controls respectively. Additionally, High resolution melt analyses was employed for genotyping of the different drug resistance markers. Results: Out of one hundred and twenty-one pregnant women sampled, the SD Bioline™ Malaria Ag P.f HRP2-based malaria rapid diagnostic test (mRDT) detected eight (0.06%) cases, the ultra-sensitive Alere™ malaria Ag P.f rapid diagnostic test mRDT had similar outcome in the same samples as detected by the HRP2-based mRDT. Microscopy and RT-PCR confirmed four out of the eight infections detected by both rapid diagnostic tests as true positive and RT-PCR further detected three false negative samples by the two mRDTs providing a sub-microscopic malaria prevalence of 3.3%. Single nucleotide polymorphism in Pfdhps gene associated with sulphadoxine resistance revealed the presence of S613 mutant genotypes in three of the seven positive isolates and isolates with mixed wild/mutant genotype at codon A613S. Furthermore, four mixed genotypes at the A581G codon were also recorded while the other Pfdhps codons (A436G, A437G and K540E) showed the presence of wild type alleles. In the Pfdhfr gene, there were mutations in 28.6%, 28.6%, and 85.7% at the I51, R59 and N108 codons respectively. Mixed wild and mutant type genotypes were also observed in 28.6% each of the N51I, and C59R codons. For the Pfcrt, two haplotypes CVMNK and CVIET were observed. The SVMNT was altogether absent. Triple mutant CVIET 1(14.3%) and triple mutant + wild genotype CVIET + CVMNK 1(14.3%) were observed. The Pfmdr1 haplotypes were single mutants YYND 1(14.3%); NFND 1(14.3%) and double mutants YFND 4(57.1%); YYDD 1(14.3%). [ABSTRACT FROM AUTHOR]

Cystic fibrosis (CF), an autosomal recessive disease, is caused by variants in both alleles of the CF transmembrane conductance regulator (CFTR) gene. A new assay based on allele-specific polymerase chain reaction and high-resolution melting analysis was developed for the detection of 18 CF-causing CFTR variants previously identified in Cuba and Latin America. The assay is also useful for zygosity determination of mutated alleles and includes internal controls. The reaction mixtures were normalized and evaluated using blood samples collected on filter paper. The evaluation of analytical parameters demonstrated the specificity and sensitivity of the method to detect the included CFTR variants. Internal and external validations yielded a 100% agreement between the new assay and the used reference tests. This assay can complement CF newborn screening not only in Cuba but also in Latin America. [ABSTRACT FROM AUTHOR]

Collecting, conserving, and using peanut germplasm depends on our ability to comprehend genetic variability in gene banks. The peanut genetic resources are not well characterized for their conservation and potential future use. Increased use of exotic and interspecific derivatives is required to reduce the yield gap, identify new alleles, and introduce them. We assessed the genetic diversity and organization of an 83-germplasm peanut population. Ninety polymorphic markers generated 326 alleles, and the similarity matrix formed three main clusters. Polymorphism information content (PIC) ranged from 0.09 to 0.85, indicating greater genetic diversity in these genotypes. Germplasm from exotic collections had the highest levels of diversity, followed by released cultivars, and interspecific derivatives had the lowest levels of diversity. The number of private alleles in interspecific derivatives, exotic collections, and cultivars was 1, 6, and 3, respectively. Overall, several SSRs showed a high probability of null alleles. In addition, gene diversity and allelic richness were 0.526 and 3.18, respectively. Analysis of molecular variance revealed variation both within and between individuals. Principal coordinate analysis and population structure analysis subdivided all germplasm lines into three populations. Bottleneck analysis revealed that all three populations experienced genetic bottlenecks, as a shifted mode was observed. This paper highlights the importance of using microsatellite markers to study the diversity of interspecific derivatives, including recently developed ones, and create effective conservation programs. [ABSTRACT FROM AUTHOR]

Lodging is one of the important reasons for rapeseed yield reduction. Increasing the lignin content in aerial part has become an effective way to improve rapeseed lodging resistance. However, knowledge of the genetic basis underlying lignin content in rapeseed is limited. Therefore, we undertook association mapping to identify quantitative trait nucleotides (QTNs) associated with lignin content in the stalk and taproot of 125 natural rapeseed accessions across three independent environments by BLUP mixed line model. Among the natural population, lignin content ranged from 6.05% and 12.76% for the stalk, and 3.21% and 12.33% for the taproot with massive phenotypic variation. Four QTL regions were identified for total lignin content in stalk and taproot, qBnADL.C09.1 and qBnADL.C09.2 with phenotypic variance ranging from 6.05% to 12.76% in stalk and BnADL.A05.1 and qBnADL.A09.1 from 3.21% to 12.33% in taproot. Lignin content significantly differed between superior and alternative alleles, with 4 haplotype groups. We identified 2 putative candidate genes based on the haplotype QTNs for lignin content, e.g., BnLI.C09 and BnRPS17. Combining with the RNA-seq data, identified 3 candidate genes with lignin pathway, e.g., BnLAC17 , BnF8H and BnDIR20. This study provides novel insights into the lodging improvement of high lignin content and also facilitates the MAS for low lignin straw selection of rapeseed. • The recycling and reuse of agricultural waste, such as rapeseed straw, requires fundamental work to understand genetic control of lignin. • In this paper, we used the GWAS and RNA-seq methods to discover superior alleles and candidate genes for lignin content in rapeseed. • This knowledge can improve the economic value by regulating lignin content by genes and superior alleles, increasing the development of biomass energy and lodging resistance of rapeseed. [ABSTRACT FROM AUTHOR]

In this paper, we describe 10 novel HLA alleles discovered, submitted and officially named in the calendar years 2022 through the end of 2023. [ABSTRACT FROM AUTHOR]