Open Access Minireview Article

Control of the MAOA-L Allele Expression through Genetic Manipulation Techniques Using CRISPR/Cas9 System

Martin L. Nelwan

Asian Journal of Biotechnology and Genetic Engineering, Page 1-10

Antisocial behaviour is antagonism behaviour. It is a behavioural disorder inherited according to X-linked chromosome inheritance pattern. This disorder comes from mutations in the MAOA gene. One of the mutations in this gene triggers the MAOA-L allele activity. The MAOA-L allele activity can trigger the expression of antagonistic actions in both healthy and unhealthy people. Maltreatment of healthy boys during childhood can lead to antagonistic actions in these children. In animal models, MAOA inhibitors can reverse the expression of antagonistic actions to healthy behaviour. Currently, this disorder in humans cannot be suppressed permanently. In the future, to suppress behavioural disorder, technologies such as end-joining homology techniques, ssODN, iPSCs and CRISPR/Cas9 system might be performed. End-joining homology, ssODN or iPSCs in combination with CRISPR/Cas9 system has succeeded to edit mutant segments in the F8 gene or F9 gene. Both genes, as well as the MAOA gene, are located in the X-chromosome. It shows that the iPSCs, ssODN or HMEJ method in combination with CRISPR/Cas9 system can significantly help the suppression of MAOA-L allele expression which triggers antagonistic actions in humans.

Open Access Original Research Article

Genetic Screening of Cowpea Varieties [Vigna unguiculata (L.) Walp.] for Aphis craccivora Resistance in the Sudano-Sahelian Zone of Cameroon

L. Iyale, J. B. Noubissie, P. M. Mapongmetsem, G. Sobda, B. Djile

Asian Journal of Biotechnology and Genetic Engineering, Page 1-15

Cowpea (Vigna unguiculata L. Walp) is a highly sought after legume of populations in the Sudano-Sahelian zone of Cameroon. Its multiple uses meet the needs of farmers because it contributes to food security and contributes to people's incomes. The use of resistant varieties is the most advantageous method because of its compatibility with integrated pest management. The objective of this study was to identify with the marker CP171 / 172 the cowpea varieties resistant to A. craccivora .Ten (10) varieties are conducted in Greenhouse for tested of resistance to aphids. The seedlings were artificially infested with five aphid nymphs and the assessment of their responses to symptoms of aphid damage was made on the basis of qualitative and quantitative criteria, namely: stem height, number of leaves, leaf surface primary, number and damage of A. craccivora. After DNA Extraction and Polymerization Chain Reaction in the Laboratory, two varieties (ENMD2 and NML50) revealed aphid resistance: these results show the effectiveness of Marker Assisted Selection in Varietal Selection programs to conserve and sustainably manage these resources.

Open Access Original Research Article

Genetic Improvement of Yield and Fruit Traits in Snake Cucumber (Cucumis melo var. flexuosus L.) by Individual Selection

Mohamed Youssef Abed

Asian Journal of Biotechnology and Genetic Engineering, Page 1-10

This investigation was undertaken during 2013-2016 to develop new and superior snake cucumber cultivars and to evaluate the efficiency of individual selection to improve yield in traditional snake cucumber populations. Moreover, genetic behaviour of variability was investigated. Three local cultivars were subjected to three cycles of individual plant selection and were ended up with selection of nine populations. These genotypes were evaluated in a field trial to study the behaviour of the tested populations and provide information on the nature of genetic variability and correlation among traits. The means of selected populations signify that there has been a remarkable change in all traits due to individual selection. However, the magnitudes of improvement varied within and between populations according to their genetic constitution and the basic criteria that selection was directed to. It is suggested that individual selection method improved stem length, whereas it did not considerably improve flowering time and the number of branches plant-1 in most populations. Otherwise, selection procedure resulted in isolation of superior populations with high yield production viz, AS1, DK2, DK3 and SG3. Some derived populations showed longer fruit length and lesser diameter when compared with their respective base populations.

The estimates of phenotypic coefficient of variation were higher than the estimates of genotypic coefficient of variation for all studied traits. High heritability coupled with high genetic advance was observed for stem length, fruit diameter and moderate estimates were observed for average fruit weight. Total yield was correlated with stem length, total number and weight of fruits and fruit diameter so that selection for any of these characters would result subsequently in an improvement of the total yield production. In the present study, selection procedure resulted in the isolation of superior populations with high yield production viz, AS1, DK2, DK3 and SG3. Fruit character was improved also through individual selection.

Open Access Original Research Article

The Role of Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) in Recognition of Pseudomonas aeruginosa in Lung Epithelial Cells

Ekong, Mercy Okon, Tarh, Jacqueline Ebob, Iroegbu, Christian Ukwuoma

Asian Journal of Biotechnology and Genetic Engineering, Page 1-8

Cystic Fibrosis Transmembrane Regulator (CFTR) plays an important role in chloride and thiocyanate ion homeostasis in human epithelial surfaces. Deletion of phenylalanine at position 508 (Δ508) leads to cystic fibrosis and dysregulation of pro-inflammatory cytokines. Pseudomonas aeruginosa gains predominance, contributing over 80% of the lung bacteria in adults with CF and this strongly correlates with the decline of pulmonary function and mortality. The research aimed at understanding the role of CFTR in response to P. aeruginosa, (the most common pathogen that colonises the airways of Cystic Fibrosis patients), with the objectives of evaluating the relative expression of epithelial and inflammatory cytokines (IL-17C and IL-6) in five (Calu3, CFBE41o, CFBE41o wt, Calu3 altered and Calu3 knockout) human bronchial epithelial cell lines after two hours of infection with P. aeruginosa using Quantitative Polymerase Chain Reaction (qPCR). It was found that Calu3 and Calu3 altered, treated cell lines significantly (p=0.05) increased in the level of IL-17C and IL-6 mRNA in all the experimental repeats compare to untreated. 

 The other three (CFBE 41o, CFBE41o wt, and Calu3 knockout) cell lines deficient of CFTR expressed low levels of these cytokines, but the level varied among the experiment in both treated and untreated cells suggesting that CFTR may modulate the level of cytokine production in bronchial epithelial cell lines. CFTR mutations have a direct effect on T cell function; enhance Th17 response which is one of the sources of IL-17. The IL-17C plays a central role in pulmonary host defence by orchestrating the accumulation and associated activity of neutrophils in the bronchoalveolar space. However, the massive neutrophils accumulation in the CF lung does not correlate with bacterial eradication but rather causes extensive tissue damage and inflammation disproportion to infection indicating that the function of neutrophils is dysregulated in CF. Therefore, knocking down IL-17C may minimise inflammation in CF patients.

Open Access Original Research Article

Variability and Molecular Characterization of Ten Onion Genotypes

A. M. A. Abo-Dahab, M. A. H. Megahed, Sara E. I. Eldessouky

Asian Journal of Biotechnology and Genetic Engineering, Page 1-15

Aim: Releasing new varieties mainly depend on evaluation the genotypes in the breeding programs. So, the objectives of this work were evaluating ten Egyptian onion genotypes for producing onion bulbs from sets, assessing the magnitude of genetic variability, heritability and genetic advance and estimating the genetic diversity among the genotypes using molecular markers. 

Place and Duration of Study: Study was conducted at Giza Research Station, Giza Governorate, Egypt, at consecutive two seasons.

Study Design and Methodology: The onion genotypes were grown from sets in RCBD with three replications. The mean performance and genetic components of twelve yield related traits were estimated as well as the genetic diversity among these genotypes by using RAPD and ISSR techniques.

Results: The results showed that the high means of leaf blade length and number of leaves/plant were obtained by Giza 20. The high means of fresh leaf blade weight/plant and culls yield were recorded by Shandaweel 1. The high means of total yield, marketable yield and average bulb weight were given by Composite 13, while Giza 20 x Ori gave the high mean of total weight loss (%). Composite 8 and H.Y. 28 recorded the high means of dry leaf weight and number of complete ring/bulb, respectively. The high means of bulb total soluble solids content (%) and bulb dry matter content (%) were recorded by Z218 white. Heritability in broad sense ranged from 0.002 for leaf number/plant to 0.67 for fresh leaf weight/plant. The difference between PCV and GCV percentages ranged between 1.72% for bulb total soluble solids content and 20.76% for number of complete ring/bulb. The genetic advance mean ranged from 0.04 for leaf number/plant to 76.65 for marketable yield. At the molecular level, RAPD and ISSR markers were used to assess the degree of polymorphism among the genotypes. The markers showed genetic diversity remarkably. The ISSR markers gave diversified results than RAPD.

Conclusion: It could be concluded that the new promising genotype composite 13 had the high response to produce bulb onions from sets. Meanwhile, the genotypes H.Y. 28 and Z 218 white had the high bulb quality traits. These results give an insight into the genetic polymorphism and the possibility of their further use in breeding programs.