The demography of the Canary Islands from a genetic perspective

Alpha-1 antitrypsin deficiency and Pi*S and Pi*Z SERPINA1 variants are associated with asthma exacerbations

INTRODUCTION AND OBJECTIVES

Asthma is a chronic inflammatory disease of the airways. Asthma patients may experience potentially life-threatening episodic flare-ups, known as exacerbations, which may significantly contribute to the asthma burden. The Pi*S and Pi*Z variants of the SERPINA1 gene, which usually involve alpha-1 antitrypsin (AAT) deficiency, had previously been associated with asthma. The link between AAT deficiency and asthma might be represented by the elastase/antielastase imbalance. However, their role in asthma exacerbations remains unknown. Our objective was to assess whether SERPINA1 genetic variants and reduced AAT protein levels are associated with asthma exacerbations.

MATERIALS AND METHODS

In the discovery analysis, SERPINA1 Pi*S and Pi*Z variants and serum AAT levels were analyzed in 369 subjects from La Palma (Canary Islands, Spain). As replication, genomic data from two studies focused on 525 Spaniards and publicly available data from UK Biobank, FinnGen, and GWAS Catalog (Open Targets Genetics) were analyzed. The associations between SERPINA1 Pi*S and Pi*Z variants and AAT deficiency with asthma exacerbations were analyzed with logistic regression models, including age, sex, and genotype principal components as covariates.

RESULTS

In the discovery, a significant association with asthma exacerbations was found for both Pi*S (odds ratio [OR]=2.38, 95% confidence interval [CI]= 1.40-4.04, p-value=0.001) and Pi*Z (OR=3.49, 95%CI=1.55-7.85, p-value=0.003)Likewise, AAT deficiency was associated with a higher risk for asthma exacerbations (OR=5.18, 95%CI=1.58-16.92, p-value=0.007) as well as AAT protein levels (OR= 0.72, 95%CI=0.57-0.91, p-value=0.005). The Pi*Z association with exacerbations was replicated in samples from Spaniards with two generations of Canary Islander origin (OR=3.79, p-value=0.028), and a significant association with asthma hospitalizations was found in the Finnish population (OR=1.12, p-value=0.007).

CONCLUSIONS

AAT deficiency could be a potential therapeutic target for asthma exacerbations in specific populations.

Environmental Factors Influencing Metal Concentrations in Scomber colias Along the Canary Islands

A total of 140 specimens of Scomber colias were collected from the Canary archipelago waters during the first semester of 2021, with 20 samples from each of the seven main islands. After analyzing the concentrations of metals (Al, Zn, Cd, Pb, Fe, and Cu) with ICP-OES, significant variations were observed among islands, with specimens from Tenerife and Gran Canaria containing higher levels of Al, Cd, and Pb, while those from Lanzarote and Fuerteventura had elevated levels of Zn, Fe, and Cu. These differences are probably related to greater anthropogenic activity around Tenerife and Gran Canaria coasts, leading to higher pollution levels, and the influence of Saharan dust and African upwelling on Lanzarote and Fuerteventura, enriching the waters with nutrients. Specific management strategies to mitigate marine pollution and continuous monitoring are crucial to safeguard marine ecosystems and to ensure food security.

The Validation of the Greulich and Pyle Atlas for Radiological Bone Age Assessments in a Pediatric Population from the Canary Islands

Bone age assessments measure the growth and development of children and adolescents by evaluating their skeletal maturity, which is influenced by various factors like heredity, ethnicity, culture, and nutrition. The clinical standards for this assessment should be up to date and appropriate for the specific population being studied. This study validates the GP-Canary Atlas for accurately predicting bone age by analyzing posteroanterior left hand and wrist radiographs of healthy children (80 females and 134 males) from the Canary Islands across various developmental stages and genders. We found strong intra-rater reliability among all three raters, with Raters 1 and 2 indicating very high consistency (intra-class coefficients = 0.990 to 0.996) and Rater 3 displaying slightly lower but still strong reliability (intra-class coefficients = 0.921 to 0.976). The inter-rater agreement was excellent between Raters 1 and 2 but significantly lower between Rater 3 and the other two raters, with intra-class coefficients of 0.408 and 0.463 for Rater 1 and 0.327 and 0.509 for Rater 2. The accuracy analysis revealed a substantial underestimation of bone age compared to chronological age for preschool- (mean difference = 17.036 months; p < 0.001) and school-age males (mean difference = 13.298 months; p < 0.001). However, this was not observed in females, where the mean difference was minimal (3.949 months; p < 0.239). In contrast, the Atlas showed greater accuracy for teenagers, showing only a slight overestimation (mean difference = 3.159 months; p = 0.823). In conclusion, the GP-Canary Atlas demonstrates overall precision but requires caution as it underestimates the BA in preschool children and overestimates it in school-age girls and adolescents.

El Hierro Genome Study: A Genomic and Health Study in an Isolated Canary Island Population

El Hierro is the smallest and westernmost island of the Canary Islands, whose population derives from an admixture of different ancestral components and that has been subjected to genetic isolation. We established the "El Hierro Genome Study" to characterize the health status and the genetic composition of ~10% of the current population of the island, accounting for a total of 1054 participants. Detailed demographic and clinical data and a blood sample for DNA extraction were obtained from each participant. Genomic genotyping was performed with the Global Screening Array (Illumina). The genetic composition of El Hierro was analyzed in a subset of 416 unrelated individuals by characterizing the mitochondrial DNA (mtDNA) and Y-chromosome haplogroups and performing principal component analyses (PCAs). In order to explore signatures of isolation, runs of homozygosity (ROHs) were also estimated. Among the participants, high blood pressure, hypercholesterolemia, and diabetes were the most prevalent conditions. The most common mtDNA haplogroups observed were of North African indigenous origin, while the Y-chromosome ones were mainly European. The PCA showed that the El Hierro population clusters near 1000 Genomes' European population but with a shift toward African populations. Moreover, the ROH analysis revealed some individuals with an important portion of their genomes with ROHs exceeding 400 Mb. Overall, these results confirmed that the "El Hierro Genome" cohort offers an opportunity to study the genetic basis of several diseases in an unexplored isolated population.

New Canary Islands Roman mediated settlement hypothesis deduced from coalescence ages of curated maternal indigenous lineages

Numerous genetic studies have contributed to reconstructing the human history of the Canary Islands population. The recent use of new ancient DNA targeted enrichment and next-generation sequencing techniques on new Canary Islands samples have greatly improved these molecular results. However, the bulk of the available data is still provided by the classic mitochondrial DNA phylogenetic and phylogeographic studies carried out on the indigenous, historical, and extant human populations of the Canary Islands. In the present study, making use of all the accumulated mitochondrial information, the existence of DNA contamination and archaeological sample misidentification in those samples is evidenced. Following a thorough review of these cases, the new phylogeographic analysis revealed the existence of a heterogeneous indigenous Canarian population, asymmetrically distributed across the various islands, which most likely descended from a unique mainland settlement. These new results and new proposed coalescent ages are compatible with a Roman-mediated arrival driven by the exploitation of the purple dye manufacture in the Canary Islands.

The early lives of the islanders: Stable isotope analysis of incremental dentine collagen from the prehispanic period of the Canary Islands

OBJECTIVES

This study presents isotopic information for incremental dentine collagen and bone bulk collagen from individuals from the Canary Islands (Tenerife and Gran Canaria) to explore dietary differences during childhood life.

MATERIALS AND METHODS

Eight individuals have been studied, which comprises 122 δ15 N and δ13 C incremental dentine measurements and eight bulk bone collagen analyses. A baseline of potentially consumed food sources has been developed for comparative purposes. A food reconstruction using isotopic transferred signals (FRUITS) model of probable contributions of each food source towards the diet of each individual has been developed. All samples but one belongs to the later period of indigenous occupation of the archipelago.

RESULTS

The dentine collagen data are presented in correlated δ13 C and δ15 N plots per individual, showing the isotopic changes throughout time. δ15 N values for each individual tend to be variable whereas δ13 C data are generally more stable with a range of +9.1 to +14‰ for δ15 N and -17.4 to -20.8‰ for δ13 C.

CONCLUSION

The isotopic analysis allows for the reconstruction of eight dietary profiles, which allow us to estimate the different dietary protein sources. The FRUITS model shows different percentages of the primary food sources for each individual. Where both δ13 C and δ15 N are elevated, this could be indicative of a higher marine contribution to the diet. There appear to be two main dietary profiles identifiable in the dataset and these may be related to changes in status or place of residence. Short-term variations in δ13 C and δ15 N and opposing co-variance of isotopic values can be indicative of nutritional stress, although metabolic changes during growth are also considered.

The genomic history of the indigenous people of the Canary Islands

The indigenous population of the Canary Islands, which colonized the archipelago around the 3rd century CE, provides both a window into the past of North Africa and a unique model to explore the effects of insularity. We generate genome-wide data from 40 individuals from the seven islands, dated between the 3rd-16rd centuries CE. Along with components already present in Moroccan Neolithic populations, the Canarian natives show signatures related to Bronze Age expansions in Eurasia and trans-Saharan migrations. The lack of gene flow between islands and constant or decreasing effective population sizes suggest that populations were isolated. While some island populations maintained relatively high genetic diversity, with the only detected bottleneck coinciding with the colonization time, other islands with fewer natural resources show the effects of insularity and isolation. Finally, consistent genetic differentiation between eastern and western islands points to a more complex colonization process than previously thought.

Stable Gender Gap and Similar Gender Trend in Chronic Morbidities between 1997-2015 in Adult Canary Population

There is little information about the trend of the gender gap in chronic morbidities and whether the trend of expansion occurs equally in the age and gender groups. The objectives were to examine the consistency and stability of the gender gap in the main self-reported chronic morbidities in the general population, and, likewise, to analyze the trend of major chronic morbidities between 1997 and 2015 in men and women across age groups. The data were extracted from the Canary Health Survey, which uses a probabilistic sampling in the population >16 years of age, for the years 1997 (n = 2167), 2004 (n = 4304), 2009 (n = 4542), and 2015 (n = 4560). The data for the twelve most frequent chronic morbidities were analyzed using logistic regression, estimating the annual change ratio between 1997 and 2015, adjusting for age and educational level. The interaction of age with the period (1997−2015) was examined to analyze the rate of change for each morbidity in the age groups. Musculoskeletal diseases, headaches, anxiety and depression, and peripheral vascular diseases showed a stable gender gap across observed years. High cholesterol and high blood pressure tended to a gap reduction, while heart disease, diabetes, and respiratory disease did not show a significant gender gap along the period. The trend of the main chronic morbidities increased similarly in men and women in all age groups, but significantly in women older than 60 years and in men older than 45 years. Aging explained a substantial part of the trend of increasing prevalence of the main chronic morbidities, but not totally. Factors other than age and education are driving the increase in chronic morbidity in older age groups.