African Population Research Articles

Inter-ethnic heterogeneity in valvular morphology and aortopathy of a worldwide bicuspid aortic valve cohort referred for TAVR

Abstract Background Bicuspid aortic valve (BAV) represents one of the most common congenital heart disease. BAV stenosis tipycally occurs in younger, low-surgical risk patients compared to tricuspid aortic valves (TAV). With the predicted expansion of trans-catheter aortic valve replacement (TAVR) into lower-risk patients, the proportion of BAV is expected to rise. Although some observational studies have investigated the characteristics of Asian versus European patients with BAV undergoing TAVR, little is known about the inter-ethnic differences within the large and diverse Asian, African, Russian, and Caucasian population. Purpose To evaluate the inter-ethnic differences of aortic valve morphology, annular size and associated aortopathy, in a worldwide population of patients with severe aortic stenosis referred for TAVR. Methods Cardiovascular multislice computed tomography data of patients with severe aortic valve stenosis referred for TAVR worldwide were obtained from the database of the Meril Life Core Lab. Inter-ethnic and epidemiological differences in terms of valvular phenotype, annular size and aortic morphology were evaluated with particular focus on patients with BAV. Results Among 12,712 patients (59% male), n=3,203 subjects (25%) exhibited a BAV morphology. According to the Siever’s BAV classification, type 1 (71%, n=2,284) was the most prevalent BAV morphology and particularly Type 1a was the most common in almost all population, with 26% exhibiting a type 0 BAV, while only 3% of the patients (n= 92) had a type 2 (Table 1). A significantly higher prevalence of severe calcium score (>1000 mm3) was found in patients with BAV compared with patients exhibiting a TAV morphology (51% vs. 32, p<0.01). Additionally, larger ascending aorta (AA) diameter (AA >40 mm) (BAV: 31% vs TAV 7%, p = 0.04), along with a higher prevalence of horizontal aorta (HA) (BAV: 20% vs TAV: 9%, p<0.01) was found in patients with BAV compared with TAV. As for inter-ethnic characteristics, there was a higher prevalence of BAV in Indian and Asian Pacific populations (respectively 43% and 28%), with the African population exhibiting the lowest prevalence (7%, n= 28, p=0.02) (Table 2). In Indian patients a higher prevalence of BAV was found in an earlier age (61-70 years old) compared to Western countries (p=0.05). Finally, smaller annular size (456±98 mm2 vs 584±99 mm2, p<0.01) and lower coronary ostia height (Asia and India: RCA 14.5±3 mm, LCA 14±2.9mm vs Caucasian and Russian: RCA 16±3.2 mm, LCA 16.9±3.3mm; p<0.01) were found in the Asian and Indian population when compared with Russian, African and Caucasian subjects. Conclusions BAV morphology, aortopathy and annular size resulted widely heterogenous according to the ethnicity and geographical origin of patients referred for TAVR worldwide. These features may lead different therapeutical decision making and outcomes following TAVR in patients with BAV.Table 1Table 2

Pharmacogenomics of CRP response to statins: a GIST consortium study

Abstract Introduction Statins are first line treatments in the primary and secondary prevention of cardiovascular disease. Prior clinical studies have shown that statins act independently of lipid lowering mechanisms to decrease C-reactive protein (CRP), a marker of inflammation. Purpose To elucidate genetic loci associated with CRP response to statins. Methods CRP response was specified as the change from baseline in log CRP after at least 4 weeks of statin therapy. Cohort level Genome-wide Association Studies (GWAS) of this CRP response was performed by linear regression analysis adjusted for baseline CRP, age, sex and BMI covariates using genetic data imputed to 1000 Genomes, testing ~10 million single nucleotide polymorphisms (SNPs) of minor allele frequency (MAF) >2%. Following quality control with EasyQC, a meta-analysis was conducted with METAL to combine GWAS results from six different cohorts of European ancestry (CARDS, FHS, JUPITER, MESA, PARC, PROSPER) within the GIST consortium. 1Mb loci regions were defined, centred +/-500kb around the lead SNP. Conditional analysis was performed using GCTA. Results There were 11,075 statin-treated individuals. The meta-analysis results revealed two loci achieving genome wide significance (P<5e-8): APOE (chr 19) and HNF1A (chr 12) (Figure 1). A signal at the CRP locus was highly suggestive (P=2.3e-7). All three loci are known to be associated with CRP levels in the absence of statin. Conditional analysis did not reveal secondary signals. The most associated variant at the APOE locus was the missense SNP rs429358, which contributes to the APOE E4 haplotype and is a risk locus for both dyslipidaemia and Alzheimer’s dementia. It is a C>T missense variant of MAF 0.12 leading to a R/C amino acid change, more common in African ancestry populations (MAF 0.27), and least common in Asian populations (MAF 0.09). A nominally significant association (P=0.09) for interaction with randomized allocation to statin v. placebo within samples derived from clinical trials supports this pharmacogenetic effect at APOE beyond genetic effects on baseline CRP levels. The most associated variant at the HNF1A locus was the intronic SNP rs11065384, which is in strong LD with the HNF1A missense SNP (rs1169288). The HNF1A locus is associated with diabetes, cholesterol levels, and coronary artery disease. There was no between-study heterogeneity at the top three loci (P>0.1), and forest plots show contribution to these signals from all 6 studies within the meta-analysis (Figure 2 A,B,C). Conclusions APOE and HNF1A are associated with CRP response to statins at the level of genome-wide significance. TheAPOE E4 signal is also known to be associated with LDL-Cholesterol response to statins, whereas the HNF1A locus is identified here for the first time as a pharmacogenetic determinant of statin response. The effect of this interindividual variability in CRP response on non-cardiovascular clinical outcomes should be elucidated.Figure 1Figure 2 A,B,C

CKD incidence, predictors & progression: African migrants vs. Non-Migrants (RODAM cohort study)

Abstract Background Limited longitudinal data exist on chronic kidney disease (CKD) in African populations undergoing epidemiological transitions. We investigated incidence, long-term predictors, and progression of CKD among Ghanaians residing in rural- and urban-Ghana, and Ghanaian migrants in the Netherlands (Amsterdam). Methods We analysed data from 2183 participants in the transcontinental population-based prospective RODAM-cohort, followed for approximately seven years. CKD incidence and its progression to end-stage renal disease (ESRD) were defined using KDIGO criteria. CKD incidence was calculated using age-and sex-standardization for those without CKD at baseline. Long-term predictors of CKD incidence were identified using one-step robust Poisson regression. CKD progression to ESRD from baseline was also assessed using robust Poisson regressions. Results Overall age-and-sex standardized CKD incidence was 11.0% (95%CI; 9.3%-12.3%). Rural and urban-Ghanaians had higher CKD incidence (12.5%;8.5%-15.5%; 12.3%;8.2%-15.8%; respectively) than Amsterdam-Ghanaians (7.6%; 5.4%-10.6%). Residence in Amsterdam was associated with lower CKD incidence compared to rural Ghana after adjustments (Incidence Rate Ratio=0.34; 0.13-0.89), but not with urban-Ghana (IRR=1.07; 0.69-1.67). CKD incidence predictors were advanced age, female sex, alcohol consumption, uric acid levels, and hypertension. CKD progression to ESRD was 2.5% (1.4%-3.6%) in rural- Ghana, 2.3% (1.3%-3.2%) in urban-Ghana and 0.0% in Amsterdam. Conclusions One-tenth of Ghanaians developed CKD over seven-years, with higher incidence in Ghana compared to Europe. Age, female sex, alcohol use, uric acid levels, and hypertension were predictive factors. CKD progression to ESRD was minimal. High CKD incidence among Ghanaians, especially among non-migrants, calls for in-depth assessment of contributing factors and targeted interventions. Key messages • We observed higher CKD Rates in Rural/Urban Ghana vs. Amsterdam:Indicating geographic Disparities. • CKD Predictors: Age, Sex, Alcohol, Uric Acid, Hypertension (Minimal ESRD Progression). Interventions target: Non-Migrant Ghanaians.

6.O. Scientific session: The unmet needs of LGBTQ+ persons and communities: perspectives from across the globe

Abstract Lesbian, gay, bisexual, transgender and queer persons suffer from rising anti-LGBTQ+ stigma. Such stigma entails laws that punish being LGBTQ+ such as in Uganda, Russia, Ghana, Iran, etc. The stigmatizing contexts have numerous health-harming effects, including perpetrating mental health harms and creating environments that hamper access & quality of services. Rising global anti-LGBTQ+ stigma and the adverse health impacts require more data on the topic to adequately dispel LGBTQ+ mis- and dis-information. This workshop will give examples of studies that examine LGBTQ+ disparities and inequities in health across different social and cultural contexts, drawing from research in Czechia, Kenya, Rwanda, and Sweden. The workshop will first outline the relevant social and cultural contexts of LGBTQ+ persons in various countries, such as attitudes, beliefs, and values. The workshop will then discuss LGBTQ+ inequities and disparities that arise from health-harming attitudes, beliefs, and values. Afterward, the workshop will discuss public health-oriented solutions & policy directions, including using data for interpretation and advocacy labs and efforts, enhancing data collection, improving knowledge and attitudes, and other implications for public health practice and policy. The workshop will open a session that will situate LGBTQ+ public health for the audience. The first study will be by Andreas Malm from the Karolinska Institute, Sweden, examining LGBTQ+ differences in mental health and treatment disparities in Sweden. This will be followed by Luis Roxo from the Karolinska Institute and Universidade NOVA de Lisboa, Portugal, discussing stressors and symptoms that shape inequalities in mental health service use. Then, Michal Pitonák from the National Institute of Mental Health, Czechia, will present treatment and outcome gaps in the mental health of LGBTQ+ persons in Czechia. Lastly, Emmy Kageha Igonya from the African Population Health Research Center, Kenya, will showcase work from a mixed-methods study with LGBTQ+ people in Rwanda and Kenya, examining access to and use of healthcare services. After the individual presentations, which will each last 7-8 minutes, the audience will be invited to a moderated 20-25-minute open discussion on the papers & how the findings can help inform public health practice & policy to address the unmet needs of LGBTQ+ populations globally. The continuing rise in anti-LGBTQ+ sentiments across the globe is problematic from a public health standpoint, given the severe health-harming effects across numerous physical and mental health states and domains. Our workshop aims to facilitate a conversation on understanding the structural situations that shape LGBTQ+ health and identifying strategies to reduce gaps in services and needs that disproportionately burden LGBTQ+ persons. Key messages • LGBTQ+ people across the globe are experiencing rising stigma and discrimination. • Rising anti-LGBTQ+ backlash disproportionately harms LGBTQ+ physical and mental health and creates gaps in care.

Population changes in a Southern Ocean krill predator point towards regional Antarctic sea ice declines

While foraging, marine predators integrate information about the environment often across wide-ranging oceanic foraging grounds and reflect these in population parameters. One such species, the southern right whale (Eubalaena australis; SRW) has shown alterations to foraging behaviour, declines in body condition, and reduced reproductive rates after 2009 in the South African population. As capital breeders, these changes suggest decreased availability of their main prey at high-latitudes, Antarctic krill (Euphausia superba). This study analysed environmental factors affecting prey availability for this population over the past 40 years, finding a notable southward contraction in sea ice, a 15–30% decline in sea ice concentration, and a more than two-fold increase in primary production metrics after 2008. These environmental conditions are less supportive of Antarctic krill recruitment in known SRW foraging grounds. Additionally, marginal ice zone, sea ice concentration and two primary production metrics were determined to be either regionally significant or marginally significant predictors of calving interval length when analysed using a linear model. Findings highlight the vulnerability of recovering baleen whale populations to climate change and show how capital breeders serve as sentinels of ecosystem changes in regions that are difficult or costly to study.

Global invasion history with climate-related allele frequency shifts in the invasive Mediterranean fruit fly (Diptera, Tephritidae: Ceratitis capitata)

The Mediterranean fruit fly (Ceratitis capitata) is a globally invasive species and an economically significant pest of fruit crops. Understanding the evolutionary history and local climatic adaptation of this species is crucial for developing effective pest management strategies. We conducted a comprehensive investigation using whole genome sequencing to explore (i) the invasion history of C. capitata with an emphasis on historical admixture and (ii) local climatic adaptation across African, European, Central, and South American populations of C. capitata. Our results suggest a stepwise colonization of C. capitata in Europe and Latin America in which Mediterranean and Central American populations share an ancestral lineage. Conversely, South American invasion history is more complex, and our results partly suggest an old secondary invasion into South America from Europe or a colonization of South America directly from Africa, followed by admixture with an European lineage. Throughout its invasive range, C. capitata is challenged with diverse climatic regimes. A genome wide association study identified a relationship between allele frequency changes and specific bioclimatic variables. Notably, we observed a significant allele frequency shift related to adaptation to cold stress (BIO6), highlighting the species’ ability to rapidly adapt to seasonal variations in colder climates.

Equity-centered adaptive sampling in sub-sewershed wastewater surveillance using census data.

Sub-city, or sub-sewershed, wastewater monitoring for infectious diseases offers a data-driven strategy to inform local public health response and complements city-wide data from centralized wastewater treatment plants. Developing strategies for equitable representation of diverse populations in sub-city wastewater sampling frameworks is complicated by misalignment between demographic data and sampling zones. We address this challenge by: (1) developing a geospatial analysis tool that probabilistically assigns demographic data for subgroups aggregated by race and age from census blocks to sub-city sampling zones; (2) evaluating representativeness of subgroup populations for COVID-19 wastewater-based disease surveillance in Davis, California; and (3) demonstrating scenario planning that prioritizes vulnerable populations. We monitored SARS-CoV-2 in wastewater as a proxy for COVID-19 incidence in Davis (November 2021-September 2022). Daily city-wide sampling and thrice-weekly sub-city sampling from 16 maintenance holes covered nearly the entire city population. Sub-city wastewater data, aggregated as a population-weighted mean, correlated strongly with centralized treatment plant data (Spearman's correlation 0.909). Probabilistic assignment of demographic data can inform decisions when adapting sampling locations to prioritize vulnerable groups. We considered four scenarios that reduced the number of sampling zones from baseline by 25% and 50%, chosen randomly or to prioritize coverage of >65-year-old populations. Prioritizing representation increased coverage of >65-year-olds from 51.1% to 67.2% when removing half the zones, while increasing coverage of Black or African American populations from 67.5% to 76.7%. Downscaling had little effect on correlations between sub-city and centralized data (Spearman's correlations ranged from 0.875 to 0.917), with strongest correlations observed when prioritizing coverage of >65-year-old populations.

A comprehensive framework for trans-ancestry pathway analysis using GWAS summary data from diverse populations.

As more multi-ancestry GWAS summary data become available, we have developed a comprehensive trans-ancestry pathway analysis framework that effectively utilizes this diverse genetic information. Within this framework, we evaluated various strategies for integrating genetic data at different levels-SNP, gene, and pathway-from multiple ancestry groups. Through extensive simulation studies, we have identified robust strategies that demonstrate superior performance across diverse scenarios. Applying these methods, we analyzed 6,970 pathways for their association with schizophrenia, incorporating data from African, East Asian, and European populations. Our analysis identified over 200 pathways significantly associated with schizophrenia, even after excluding genes near genome-wide significant loci. This approach substantially enhances detection efficiency compared to traditional single-ancestry pathway analysis and the conventional approach that amalgamates single-ancestry pathway analysis results across different ancestry groups. Our framework provides a flexible and effective tool for leveraging the expanding pool of multi-ancestry GWAS summary data, thereby improving our ability to identify biologically relevant pathways that contribute to disease susceptibility.

Implementation of a genotyped African population cohort, with virtual follow-up: A feasibility study in the Western Cape Province, South Africa

Background There is limited knowledge regarding African genetic drivers of disease due to prohibitive costs of large-scale genomic research in Africa. Methods We piloted a cost-effective, scalable virtual genotyped cohort in South Africa, with participant recruitment using a tiered informed consent model and DNA collection by buccal swab. Genotype data was generated using the H3Africa Illumina micro-array, and phenotype data was derived from routine health data of participants. We demonstrated feasibility of nested case control genome wide association studies using these data for phenotypes type 2 diabetes mellitus (T2DM) and severe COVID-19. Results 2267346 variants were analysed in 459 participant samples. 78.6% of SNPs and 74% of samples passed quality control (QC). Principal component analysis showed extensive ancestry admixture in study participants. For 1780 published COVID-19-associated variants, 3 SNPs in the pre-imputation data and 23 SNPS in the imputed data were significantly associated with severe COVID-19 cases compared to controls. For 2755 published T2DM associated variants, 69 SNPs in the pre-imputation data and 419 SNPs in the imputed data were significantly associated with T2DM cases when compared to controls. Conclusions The results shown here are illustrative of what will be possible as the cohort expands in the future. Here we demonstrate the feasibility of this approach, recognising that the findings presented here are preliminary and require further validation once we have a sufficient sample size to improve statistical significance of findings. We implemented a genotyped population cohort with virtual follow up data in a resource-constrained African environment, demonstrating feasibility for scale up and novel health discoveries through nested case-control studies.

The Black and African American Connections to Parkinson’s Disease (BLAAC PD) study protocol

Determining the genetic contributions to Parkinson’s disease (PD) across diverse ancestries is a high priority as this work can guide therapeutic development in a global setting. The genetics of PD spans the etiological risk spectrum, from rare, highly deleterious variants linked to monogenic forms with Mendelian patterns of inheritance, to common variation involved in sporadic disease. A major limitation in PD genomics research is lack of racial and ethnic diversity. Enrollment disparities have detrimental consequences on the generalizability of results and exacerbate existing inequities in care. The Black and African American Connections to Parkinson’s Disease (BLAAC PD) study is part of the Global Parkinson’s Genetics Program, supported by the Aligning Science Across Parkinson’s initiative. The goal of the study is to investigate the genetic architecture underlying PD risk and progression in the Black and/or African American populations. This cross-sectional multicenter study in the United States has a recruitment target of up to 2,000 individuals with PD and up to 2,000 controls, all of Black and/or African American ancestry. The study design incorporates several strategies to reduce barriers to research participation. The multifaceted recruitment strategy aims to involve individuals with and without PD in various settings, emphasizing community outreach and engagement. The BLAAC PD study is an important first step toward informing understanding of the genetics of PD in a more diverse population.

An estimation of global genetic prevalence of PLA2G6-associated neurodegeneration

BackgroundPLA2G6-associated neurodegeneration (PLAN) comprises three diseases with overlapping features: infantile neuroaxonal dystrophy (INAD), atypical neuroaxonal dystrophy (atypical NAD), and PLA2G6-related dystonia-parkinsonism. INAD is an early onset disease characterized by progressive loss of vision, muscular control, and mental skills. The prevalence of PLA2G6-associated diseases has not been previously calculated.MethodsTo provide the most accurate prevalence estimate, we utilized two independent approaches: database-based approach which included collecting variants from ClinVar, Human Gene Mutation Database (HGMD) and high confidence predicted loss-of-function (pLoF) from gnomAD (Rare Genomes Project Genetic Prevalence Estimator; GeniE), and literature-based approach which gathered variants through Mastermind Genomic Search Engine (Genomenon, Inc). Genetic prevalence of PLAN was calculated based on allele frequencies from gnomAD, assuming Hardy–Weinberg equilibrium.ResultsIn the PLA2G6 gene, our analysis found 122 pathogenic, 82 VUS, and 15 variants with conflicting interpretations (pathogenic vs VUS) between two approaches. Allele frequency was available for 58 pathogenic, 42 VUS, and 15 conflicting variants in gnomAD database. If pathogenic and/or conflicting variants are included, the overall genetic prevalence was estimated to be between 1 in 987,267 to 1 in 1,570,079 pregnancies, with the highest genetic prevalence in African/African-American (1 in 421,960 to 1 in 365,197) and East-Asian (1 in 683,978 to 1 in 190,771) populations.ConclusionOur estimates highlight the significant underdiagnosis of PLA2G6-associated neurodegeneration and underscores the need for increased awareness and diagnostic efforts. Furthermore, our study revealed a higher carrier frequency of PLA2G6 variants in African and Asian populations, stressing the importance of expanded genetic sequencing in non-European populations to ensure accurate and comprehensive diagnosis. Future research should focus on confirming our findings and implementing expanded sequencing strategies to facilitate maximal and accurate diagnosis, particularly in non-European populations.

Micro-XCT analysis of anatomical features and dimensions of the incisive canal: implications for dental implant treatment in the anterior maxilla

BackgroundThis study used micro-focus X-ray Computed Tomography (micro-XCT) to examine the anatomical differences and dimensions of the maxillary incisive canal (MIC) in a South African population. The accurate imaging yielded dependable results that support earlier research and enhance anterior maxilla surgery planning. Furthermore, these anatomical features are compared between various racial and gender groupings in the study.MethodsUsing a micro-XCT scanner, 108 human cadaver skulls from the Pretoria Bone Collection were scanned and included in the study. Advanced volume rendering software was employed for measuring the MIC length, diameter, shape, and the buccal bone wall measurements in relation to the MIC.ResultsSignificant anatomical variation in the size and shape of the MIC was identified in the population, with variations seen between racial and gender groups. The incisive foramen (ICO) mean diameter was 6.61 mm, and the MIC length varied from 4.96 to 20.10 mm. There were significant differences in the buccal alveolar bone height between different ethnic groups and gender. Regarding morphological patterns in coronal and sagittal views, single canals were more common in the black population while Y-shaped canals were more common in the white population. The study also introduced a new metric by measuring the mean distances between teeth #11 and #21 and the ICO (1.83 mm and 1.88 mm respectively).ConclusionsThe complex anatomical differences of the MIC in a South African population were clarified. Clinicians should be aware of tooth sockets in near proximity to the MIC and perform accurate preoperative assessment using sophisticated 3-D imaging and preferable guided implant placement in the anterior maxilla.

Household air pollution and respiratory health in Africa: persistent risk and unchanged health burdens.

Despite evidence emerging from the Global Burden of Disease studies that biomass use and household air pollution are declining globally, with important positive health impacts for households in low- and middle-income countries, these trends have not been equally documented in African countries. This review describes the state of household air pollution exposure and its relationship with respiratory disease in Africa. African studies on this topic are limited, and generally focus on respiratory infections. Most evidence emerge from models based on the Global Burden of Disease data, and from limited individual epidemiological studies across the continent. More than 80% of the African population is exposed to household air pollution. Women and children continue to bear the substantial burden of exposure. Evidence from limited exposure-response studies strongly points to household air pollution being the major driver of acute and chronic respiratory diseases on the continent. Respiratory infections, particularly in children, and other chronic respiratory diseases, are strongly attributable to household air pollution. Elimination of such exposures through interventions such as cleaner fuels and preferably, electricity, is critical to improving respiratory health on the continent.

A 6-month Review of pRBC Transfusion Practices in a Tertiary Institution in Brooklyn, NY

Abstract Introduction/Objective Many factors are considered when managing hospital blood inventory. Because demographics and types of services vary per institution, a conscious effort to survey the prevalence of different blood types is necessary to make better predictions of inventory adequacy and decrease inappropriate use of O pRBC units. Methods/Case Report We reviewed the transfused pRBC units between October 2023 and March 2024 to determine the number of patients receiving ABO-type specific units and the number of D+ patients receiving D- units. Results (if a Case Study enter NA) After review, the patient population was found to be approximately 80% African Americans. Most of our patients were D+ with a monthly average of 224 patients. In contrast, we served 15 D- patients per month (PPM). Between 21-33% of D+ patients received D- units. O blood type was the most common, with an average of 224 PPM, followed by A blood type at 57 PPM and B blood type at 51 PPM. Since we see an average of 10 AB blood type patients monthly, it wasn’t surprising that they all received non-type specific units. Noteworthy is the significant proportion of A and B blood type patients receiving ABO type-specific units, ranging from 74-85% for A blood type and 70-90% for B blood type. Conclusion Our institution’s commitment to hemovigilance and conservation of O units is evident in the relatively high percentage of patients receiving ABO-type specific units. It is worth noting that we are a tertiary institution mainly serving the African American population. This creates a unique need to maintain adequate O units for emergency transfusion and increase the possibility of using O units to meet our sickle cell disease patients’ needs. Given that our demographics are primarily D+, some of our D- units were utilized in D+ patients. By adhering to our transfusion protocol and surveying our patients’ ABO and D blood types, we can anticipate our inventory needs and help prevent future O pRBC shortages.

Simultaneous Genotyping of Three SNVs, rs5471, rs5472, and rs2000999 Involved in Serum Haptoglobin Levels by Fluorescent Probe-Based Melting Curve Analysis.

Haptoglobin (Hp) is a hemoglobin-binding acute-phase serum protein. Several single nucleotide variations (SNVs) within the Hp gene (HP) or Hp-related protein gene (HPR), such as rs5471 (A>C) and rs5472 (A>G) in HP promoter region and rs2000999 (G>A) in intron 2 of HRP, are suggested to correlate with the serum Hp levels. To determine these three SNVs simultaneously, a genotyping assay based on duplex dual-labeled fluorescent probes was developed. The method was then validated by analyzing genomic DNA from 121 Ghanaian and two Japanese subjects who had been previously genotyped for rs5471, rs5472, and rs2000999. Both rs5471 and rs5472 could be determined as haplotypes with a single FAM-labeled fluorescent probe, and rs2000999 could be genotyped with a HEX-labeled fluorescent probe. The results obtained with the present method were consistent with the previous results except for those of three Ghanaian subjects. All three subjects appear to have multiple HPR copy number variants characteristic of African populations, which may have led to incorrect results during previous genotyping. This method allows us to genotype these three SNVs in a relatively large number of samples, especially in African populations where rs5471 is uniquely distributed.

Insights from a population grid of South Africa: An applied spatial satellite data analysis

The present study explores the reliability and accuracy of various spatial mapping methodologies in estimating and presenting the spatial characteristic and dynamics (location, distribution, density, and size) of the population in South Africa. As a basic underlying concept, the study first explores spatial heterogeneity, that is, that every location is related to every other location, and those nearby are related stronger. This study, therefore, illustrates the spatial relationships between locations and the spatial pattern of the population in South Africa. Analyzing the spatial images determines the extent of such influence and the nature of the spatial patterns. To this end, a granular gridded population dataset was derived using satellite image data, and the NASA’s Socioeconomic Data and Applications Center gridded population of the world version 4 population images and datasets were used. Several spatial data models and geostatistical applications were applied to study the spatial characteristics and dynamics of the population of South Africa from 2000 to 2020. Spatial analysis was performed using R-Studio, QGIS, and GeoDa. Among others, the results point to the fact that the South African population is very densely located that population density decreases marginally outward and suggests that the underlying process for the population distribution is stationary. This study proposes that it is indeed possible to reliably and accurately estimate and present gridded population images and datasets using spatial and geostatistical methodologies.

Meshwork choreography: a pragmatic approach to collaborative embodied learning in South African higher education

ABSTRACT The diversity of the South African higher educational student population requires innovative pedagogical strategies that facilitate transformative and collaborative embodied learning. This article demonstrates how the choreographic process emerges from the context of multiculturalism through a pragmatic learning approach called meshwork choreography. Meshwork suggests an interwoven relation that emphasises the ever-evolving nature of relationships within an environment. Choreography as meshwork is where the choreographer does not impose preconceived ideas on the dancers but rather facilitates a collaborative and exploratory process. The research employed a conceptual framework of phenomenography, embodied and collaborative learning to frame the discussion towards a model of how choreography functions as meshwork. Composition and design processes in and of themselves embrace transformative learning through collaborative, embodied, and relational practices and are bolstered when they converge within the creation of choreographic work. This article reflects on students’ experiences in the Performing Arts Dance Stream at Tshwane University of Technology in conceptualising choreography as meshwork. Phenomenography was adopted as the research methodology, where data was analysed within phenomenographic categories. The article offers a South African perspective, informed by Ubuntu, of a meshwork model for the benefits of applying transformative learning through choreography within a higher education dance context.

Dimensional and Morphometric Variations of the Sella Turcica in Adult South African Population: Sex, Age, and Ethnic-related Changes

Dimensional and Morphometric Variations of the Sella Turcica in Adult South African Population: Sex, Age, and Ethnic-related Changes

Genetic, breeding and environmental parameters for yellow sugarcane aphid (Sipha flava) damage in advanced South African sugarcane breeding populations

Yellow sugarcane aphid (YSA), a native pest of temperate and subtropical regions in North America, has spread to many regions of the world including KwaZulu-Natal and Mpumalanga sugarcane growing regions of South Africa. Cultivar differences to YSA damage have been observed in Mpumalanga where high infestation levels occur. The objectives of this study were to determine genetic, breeding, and environmental parameters for YSA damage and implications on breeding for resistance. Data for YSA damage were collected from 12 genotype populations planted in Mpumalanga. There were significant (p < 0.0001) genotype effects indicating genetic variability. Significant (p < 0.01) environment effects showed that YSA damage in February was significantly (p < 0.05) higher than in December. The significant (p < 0.01) genotype by environment interaction indicated February as the best month to screen for YSA. Higher broad sense heritability (> 0.70) suggests selecting resistant genotypes would be effective. Data collected in February produced higher broad sense heritability (> 0.80) than in December (< 0.70) suggesting February as the preferred month to score for damage. The proportion of resistant genotypes was 16.5% (range 2–34%), indicating the presence of resistant in South African advanced genotype populations. Evaluation of released cultivars showed N36, N49 and N71 are resistant while N57 and N73 are susceptible.

The 9 bp Deletion between the Mitochondrial COII and Lysine tRNA Genes in a Caucasian Population with Cognitive Disorders: An Observational Study.

The loss of one of the two copies of the 9 bp tandem repeat sequence (CCCCCTCTA) located in the small non-coding region between the cytochrome oxidase II (COII) and the lysine tRNA genes in human mtDNA has been reported to be polymorphic in Asian, Oceanian and Sub-Saharan African populations, but it has rarely been observed in Europe. In this study, we will evaluate the possible association between the MIC9D polymorphism and cognitive disorders. A genetic analysis of unrelated Sicilian patients with cognitive deficits was performed to identify the 9 bp deletion MIC9D polymorphism. The MIC9D polymorphism was found in six patients, whereas this variant was absent in control individuals without cognitive deficits. The patients with the MIC9D polymorphism exhibited more complex clinical presentations; in particular, all had neuromuscular disorders and five also presented with behavioral disorders. The present study suggests a potential association between the MIC9D polymorphism and cognitive impairment with concurrent neuromuscular and behavioral involvement.