Genetic diversity, population structure and inter-trait relationships of combined heat and drought tolerant early-maturing maize inbred lines from west and central Africa

Open Access Journal; Published online: 04 Sept 2020Adequate knowledge and understanding of the genetic diversity and inter-trait relationships among elite maize inbred lines are crucial for determining breeding strategies and predicting hybrid performance. The objectives of this study were to investigate the genetic diversity of 162 early maturing white and yellow tropical maize inbred lines, and to determine the population structure, heterotic groups and inter-trait relationships among the lines. Using 9684 DArT single nucleotide polymorphism (SNP) markers, a gene diversity (GD) of 0.30 was recorded for the inbred lines with polymorphic information content (PIC) ranging from 0.08 to 0.38. The genetic relatedness among the inbred lines evaluated revealed six different groups based on the history of selection, colour of endosperm and pedigree. The genotype-by-trait (GT) biplot analysis identified inbred 1 (TZEI 935) as outstanding in terms of combined heat and drought (HD) tolerance with the base index analysis identifying 15 superior inbreds in the HD environment. A wide range of genetic variability was observed among the inbred lines, indicating that they are an invaluable resource for breeding for HD tolerance in maize breeding programmes, especially in West and Central Africa

Use of GGE biplot for targeting early maturing maize cultivars to mega-environments in West Africa

Maize (Zea mays L.) is an important staple food consumed by people with varying food preferences and socio-economic backgrounds in West Africa (WA). Genotype by environment interactions (G 7E) exist in WA implying the need for extensive testing of cultivars in multiple environments over years before cultivar realistic recommendations can be made. This study examined the effect of G 7E on the performance and stability of early cultivars and to identify core test locations in the mega-environments of WA. Across locations, 2004 TZE-W Pop STR C4 produced the highest grain yield and was the most stable cultivar. DMR-ESRW QPM produced the lowest yield. The test environments contributed about 83.4% of the total variation in grain yield, while genotypes accounted for 1.5% and G 7 E, 11%. Test environments were classified into four mega-environments, namely, Katibougou, Sotouboua, Ejura, and Bagou as the first group; the second group consisted of Manga, Nyankpala, Bagauda, Yendi, Angaredebou, Mokwa, Katibougou, and Zaria; while the third group comprise of Ativeme, and Ikenne; and the fourth, Ina. Test locations Ejura, Sotouboua and Bagou and Katibougou were highly correlated in their ranking of the genotypes in group 1, suggesting that a promising early maturing cultivar selected in one of these locations in one country will also be suitable for production in the other locations within the same mega-environments in different countries. Kita was identified as the ideal location, while Zaria was close to the ideal location.Le ma\uefs (Zea mays L.) est une nourriture principale consomm\ue9 par des personnes \ue0 pr\ue9f\ue9rence alimentaires et un pass\ue9 socio-\ue9conomique vari\ue9s en Afrique de l'Ouest. Une interaction G\ue9notype et Environnement (G 7E) \ue9tait trouv\ue9e, impliquant ainsi le besoin en test extensive des cultivars sur plusieurs ann\ue9es avant toute recommandation. Le but de cette \ue9tude \ue9tait d'examiner l'effet G 7E sur la performance et la stabilit\ue9 des cultivars pr\ue9coces, ainsi que d'identifier le test principal de milieu dans les m\ue9ga-environnements de l'Afrique de l'Ouest. A travers les milieux, 2004 TZE-W Pop STR C4 avait produit le rendement en grain le plus \ue9lev\ue9 et \ue9tait le cultivar le plus stable. DMR-ESRW QPM avait induit le rendement le moins \ue9lev\ue9. La contribution du test d'environnements \ue9tait d'environ 83.4% de la variation totale du rendement en grain, pendant que les g\ue9notypes et G 7 E pr\ue9sentaient 1.5% et 11%, respectivement. Les tests d'environnements \ue9taient classifi\ue9s en quatre m\ue9ga-environnements \ue0 savoir, Katibougou, Sotouboua, Ejura, and Bagou comme premier groupe; Manga, Nyankpala, Bagauda, Yendi, Angaredebou, Mokwa, Katibougou, and Zaria comme deuxi\ue8me groupe, alors que le troisi\ue8me groupe comprenait Ativeme, et Ikenne et le quatri\ue8me, Ina. Le test de milieux Ejura, Sotouboua, Bagou et Katibougou \ue9taitent hautement corr\ue9l\ue9 sur le plan ranking des g\ue9notypes au sein du groupe 1, sugg\ue9rant qu'un cultivar pr\ue9coce promettant s\ue9lectionn\ue9 dans un de ces milieux dans un pays sera appropri\ue9 pour la production dans d'autres milieux au sein des m\ueames m\ue9ga-envoronnements dans diff\ue9rents pays. Kita \ue9tait identifi\ue9 comme un milieu ideal, alors que Zaria \ue9tait proche du milieu ideal

Linking Structural Racism and Discrimination and Breast Cancer Outcomes: A Social Genomics Approach

We live in a society where individuals and communities are marginalized because of their race or ethnicity. This structural inequity extracts enormous health and societal costs, decreasing access to cancer care and increasing health disparities, especially among the most vulnerable. In an effort to identify causes of disparities, we have incorporated individual sociodemographic characteristics (eg, income and education) and other social determinants of health (eg, access to care, insurance, and transportation needs), as well as biologic markers (eg, genetic predisposition to disease) that can serve as therapeutic targets into our research

Food Allergy in Ghanaian Schoolchildren: Data on Sensitization and Reported Food Allergy

Background: Epidemiological data on food allergy are scarce in African countries. We studied the prevalence of food sensitization in Ghanaian schoolchildren. Methods: Children (5-16 years; n = 1,714) from 9 Ghanaian schools were given parental consent to participate in the study. Adverse reactions and food consumption were determined by a questionnaire and atopy by skin prick testing (SPT) to peanut and 6 fruits. Subjects with positive SPTs were considered cases (n = 43) and matched with at least 1 control (n = 84), using age, sex, and school as matching criteria. Serum samples from case-control sets were analyzed for specific IgE (sIgE) to foods that elicited a positive SPT response in cases. Results: Overall, 11% of 1,407 children reported adverse reactions to foods, and 5% of 1,431 children showed a positive SPT reaction mostly directed against peanut and pineapple (both 2%). Although there was a positive association between adverse reactions and SPT responses to any food allergen in the urban children (adjusted OR = 3.6, 95% CI 1.2-10.8), most of the reported adverse reactions were not in children showing an SPT reaction to the specific food item. sIgE sensitization was very variable for the different foods, ranging from 0 to 100% in cases, and from 0 to 25% among controls. High IgE levels for a food item significantly increased the risk of SPT positivity to any food item in the urban, but not in the rural, schoolchildren. Conclusions: Specific foods were identified to be allergenic in Ghana. We show a good association between SPT and sIgE in urban, but not in rural, schoolchildren. However, there was no clear association between reported adverse reactions to food and SPT or sIgE.Host-parasite interactio

High body mass index is not associated with atopy in schoolchildren living in rural and urban areas of Ghana

Background: Factors which determine the development of atopy and the observed rural-urban gradient in its prevalence are not fully understood. High body mass index (BMI) has been associated with asthma and potentially atopy in industrialized countries. In developing countries, the transition from rural to urban areas has been associated with lifestyle changes and an increased prevalence of high BMI; however, the effect of high BMI on atopy remains unknown in this population. We therefore investigated the association between high BMI and atopy among schoolchildren living in rural and urban areas of Ghana. Methods: Data on skin prick testing, anthropometric, parasitological, demographic and lifestyle information for 1,482 schoolchildren aged 6-15 years was collected. Atopy was defined as sensitization to at least one tested allergen whilst the Centres for Disease Control and Prevention (CDC, Atlanta) growth reference charts were used in defining high BMI as BMI >= the 85(th) percentile. Logistic regression was performed to investigate the association between high BMI and atopy whilst adjusting for potential confounding factors. Results: The following prevalences were observed for high BMI [Rural: 16%, Urban: 10.8%, p < 0.001] and atopy [Rural: 25.1%, Urban: 17.8%, p < 0.001]. High BMI was not associated with atopy; but an inverse association was observed between underweight and atopy [OR: 0.57, 95% CI: 0.33-0.99]. Significant associations were also observed with male sex [Rural: OR: 1.49, 95% CI: 1.06-2.08; Urban: OR: 1.90, 95% CI: 1.30-2.79], and in the urban site with older age [OR: 1.76, 95% CI: 1.00-3.07], family history of asthma [OR: 1.58, 95% CI: 1.01-2.47] and occupational status of parent [OR: 0.33, 95% CI: 0.12-0.93]; whilst co-infection with intestinal parasites [OR: 2.47, 95% CI: 1.01-6.04] was associated with atopy in the rural site. After multivariate adjustment, male sex, older age and family history of asthma remained significant. Conclusions: In Ghanaian schoolchildren, high BMI was not associated with atopy. Further studies are warranted to clarify the relationship between body weight and atopy in children subjected to rapid life-style changes associated with urbanization of their environments.Host-parasite interactio

Urban-rural differences in the gene expression profiles of Ghanaian children

Host-parasite interactio

The impact of the COVID-19 pandemic on routine HIV care and cervical cancer screening in North-Central Nigeria

Introduction: Cervical cancer is the fourth most diagnosed cancer among women globally, with much of the burden being carried by women in limited-resource settings often worsened by the high prevalence of HIV. Furthermore, the COVID-19 pandemic disrupted organized screening efforts and HIV management regimens worldwide, and the impact of these disruptions have not been examined in these settings. The purpose of this paper is to describe whether uptake of cervical cancer screening and HIV management changed before, during, and since the COVID-19 pandemic in North-Central Nigeria. Methods: Longitudinal healthcare administration data for women who obtained care between January 2018 and December 2021 were abstracted from the AIDS Prevention Initiative Nigeria (APIN) clinic at Jos University Teaching Hospital. Patient demographics, pap smear outcomes, and HIV management indicators such as viral load and treatment regimen were abstracted and assessed using descriptive and regression analyses. All analyses were conducted comparing two years prior to the COVID-19 pandemic, the four quarters in 2020, and the year following COVID-19 restrictions. Results: We included 2304 women in the study, most of whom were between 44 and 47 years of age, were married, and had completed secondary education. About 85% of women were treated with first line highly active retroviral therapy (HAART). Additionally, 84% of women screened using pap smear had normal results. The average age of women who sought care at APIN was significantly lower in Quarter 3, 2020 (p = 0.015) compared to the other periods examined in this study. Conversely, the average viral load for women who sought care during that period was significantly higher in adjusted models (p < 0.0001). Finally, we determined that the average viral load at each clinic visit was significantly associated with the period in which women sought care. Conclusions: Overall, we found that COVID-19 pandemic mitigation efforts significantly influenced women’s ability to obtain cervical cancer screening and routine HIV management at APIN clinic. This study buttresses the challenges in accessing routine and preventive care during the COVID-19 pandemic, especially in low-resource settings. Further research is needed to determine how these disruptions to care may influence long-term health in this and similar at-risk populations. © 2023, The Author(s).Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Use of GGE biplot for targeting early maturing maize cultivars to mega environments in West Africa

Maize (Zea mays L.) is an important staple food consumed by people with varying food preferences and socioeconomic backgrounds in West Africa (WA). Genotype by environment interactions (G×E) exist in WA implying the need for extensive testing of cultivars in multiple environments over years before cultivar realistic recommendations can be made. This study examined the effect of G×E on the performance and stability of early cultivars and to identify core test locations in the mega-environments of WA. Across locations, 2004 TZE-W Pop STR C4 produced the highest grain yield and was the most stable cultivar. DMR-ESRW QPM produced the lowest yield. The test environments contributed about 83.4% of the total variation in grain yield, while genotypes accounted for 1.5% and G × E, 11%. Test environments were classified into four mega-environments, namely, Katibougou, Sotouboua, Ejura, and Bagou as the first group; the second group consisted of Manga, Nyankpala, Bagauda, Yendi, Angaredebou, Mokwa, Katibougou, and Zaria; while the third group comprise of Ativeme, and Ikenne; and the fourth, Ina. Test locations Ejura, Sotouboua and Bagou and Katibougou were highly correlated in their ranking of the genotypes in group 1, suggesting that a promising early maturing cultivar selected in one of these locations in one country will also be suitable for production in the other locations within the same mega-environments in different countries. Kita was identified as the ideal location, while Zaria was close to the ideal location

Molecular Diagnosis of Schistosoma Infections in Urine Samples of School Children in Ghana

Host-parasite interactio