Interpopulation Study Research Articles

Croatian genetic heritage: an updated Y-chromosome story

AimTo analyze an additional set of Y-chromosome genetic markers to acquire a more detailed insight into the diversity of the Croatian population.MethodsA total of 518 Yfiler Plus profiles were genotyped. Allele frequencies, haplotype frequencies, and haplotype diversity were calculated by using the STRAF software v. 2.0.4. Genetic distances were quantified by Rst with AMOVA online tool from the YHRD. The evolutionary history was inferred with the neighbor-joining method of phylogenetic tree construction in the MEGAX software. Whit Athey's Haplogroup Predictor v. 5 was used for additional comparison with regional and other European populations.ResultsA total of 507 haplotypes were used for genetic STR analysis. An interpopulation study on 17 Y-STR markers showed the lowest genetic diversity between the Croatian and Bosnian-Herzegovinian populations and the highest between the Croatian and Irish populations. Additional interpopulation comparison with the original 27 Y-STR markers (for the population with available data) was also performed. A total of 518 haplotypes were used in the determination of haplogroup diversity. Haplogroup I with its sublineage I2a expressed the highest prevalence. The second most prevalent haplogroup was R, with its major sublineage R1a, except for the subpopulation of Hvar, where E1b1b was the second most prevalent haplogroup. Rare haplogroups also confirmed in this study were L, T, and Q. G1 was detected for the first time in the Croatian population.ConclusionWe obtained a new insight into the differences between examined subpopulations of Croatia and their possible (dis)similarities with neighboring and distant populations.

Genetic interrelationships of Spirometra erinaceieuropaei (Cestoda: Diphyllobothriidea), the causative agent of sparganosis in Europe.

The geographic distribution of Spirometra erinaceieuropaei (Cestoda: Diphyllobothriidea), the causative agent of food/water-borne sparganosis, is restricted to Europe, where infected canids, felids, mustelids, suids, and reptiles have been documented from Poland, Ukraine, Belarus, Russia, Serbia, Estonia, Latvia, and Finland. The main objective of the current study was to map the molecular divergence of S. erinaceieuropaei from Finland using the complete sequences of the mitochondrial cytochrome c oxidase subunit 1 gene (cox1 mtDNA). Seven cox1 haplotypes were determined in 15 tapeworms from Eurasian lynx (Lynx lynx) from three localities in southern Finland. In addition, the first inter-population study of S. erinaceieuropaei based on currently obtained data on cox1 from Finland and previously published data from Finland, Latvia, Ukraine, and Poland, was performed. The haplotype network showed a star-like pattern without specific subdivision of lineages according to the locality. Samples from Finland, Latvia, and Poland shared several haplotypes and formed the common Baltic lineage. The haplotype of S. erinaceieuropaei from Ukraine was unique and placed on a separate mutational pathway, suggesting a different lineage of the parasite.

Distribution of Tetrodotoxin in Pacific Oysters (Crassostrea gigas).

A potent and heat-stable tetrodotoxin (TTX) has been found to accumulate in various marine bivalve species, including Pacific oysters (Crassostrea gigas), raising a food safety concern. While several studies on geographical occurrence of TTX have been conducted, there is a lack of knowledge about the distribution of the toxin within and between bivalves. We, therefore, measured TTX in the whole flesh, mantle, gills, labial palps, digestive gland, adductor muscle and intravalvular fluid of C. gigas using liquid chromatography-tandem mass spectrometry. Weekly monitoring during summer months revealed the highest TTX concentrations in the digestive gland (up to 242 µg/kg), significantly higher than in other oyster tissues. Intra-population variability of TTX, measured in the whole flesh of each of twenty animals, reached 46% and 32% in the two separate batches, respectively. In addition, an inter-population study was conducted to compare TTX levels at four locations within the oyster production area. TTX concentrations in the whole flesh varied significantly between some of these locations, which was unexplained by the differences in weight of flesh. This is the first study examining TTX distribution in C. gigas and the first confirmation of the preferential accumulation of TTX in oyster digestive gland.

Chemotypes of Juniperus oxycedrus in Bulgaria and the antimicrobial activity of galbuli essential oils

Juniperus oxycedrus L. (Cupressaceae Bartlett) sensu lato is a species of high phenotypic and phytochemical variability. There is interest in the development of this species into cultivated crop because wild collection of galbuli or leaves result in significant variation in the essential oil (EO) profile and bioactivity. The objectives of this study were tо assess the variability of EO content and composition of J. oxycedrus collected at 20 populations (interpopulation) across Bulgaria and also intrapopulation variability using advanced statistical methods, and to identify promising clones that can be propagated and further investigated under cultivation. Overall, the EO yield of leaves varied from 0.03 % to 0.20 % (interpopulation), from 0.04 % to 0.18 % (intrapopulation), whille the galbuli EO varied from 0.83 % to 2.6 % (interpopulation) and from 1.2 % tо 1.9 % (intrapopulation), respectively. Monoterpenes was the predominant chemical class of galbuli ЕO, ranging from 53.4%to–69.5% (intrapopulation), while in leaf EO, the predominant class was sesquiterpenes (46.2 %–67.4 %) (intrapopulation). The major constituents (α-pinene, limonene, α-curcumene, γ-cadinene, δ-cadinene, manoyl oxide, germacrene D, β-caryophyllene, α-caryophyllene, caryophyllene oxide) of leaf EO were considered for grouping the populations in eight chemotypes, whereas twenty-seven chemical groups were established for the interpopulation study. The EO of galbuli in the interpopulation study formed five chemical groups. The present study is the first report to demonstrate such variability of EO between and within the populations of J. oxycedrus, and the first report to identify so many chemical groups based on the leaf and galbuli EO. Galbuli ЕO showed different аntimicrobial activity towards Yersinia enterocolitica, Staphylococcus aureus subsp. aureus, Enterococcus faecalis, Streptococcus pneumoniae, Candida kruseii, and C. tropicalis. This study identified promising genetic material (clones) that could be further propagated and developed into cultivars for commercial production of J. oxycedrus oil with desirable profile, aroma, and bioactivity to meet specific market demands.

Anatomic variations in glenohumeral joint: an interpopulation study

BackgroundThis study focused on the unique aspect of investigating shoulder morphometric differences between 2 distinct populations.MethodsWe used 90 computed tomography images of cadaveric shoulders for this study; 45 scans belonged to the South African (SA) cohort (49.74 ± 15.4 years) and the rest were Swiss (CH; 53.8 ± 21 years). The articulating surfaces of the glenohumeral joint were extracted, and their morphometric features, such as head circular diameter, glenoid and humeral head radius of curvature, head height, and humeral height, were measured.ResultsThe mean interpopulation difference in the circular diameter of the humerus was 2.0 mm (P = .017) and 1.86 mm (P > .05) in the anterior-posterior and superior-inferior directions, respectively. The difference in the radius of curvature between the populations was 1.17 mm (P = .037). The SA shoulders were found to be longer than the CH shoulders by 8.4 mm (P > .05). There was no significant difference in the glenoid radius of curvature. The SA shoulders had higher glenohumeral mismatch (P = .005) and lower conformity index (P = .001) in comparison to the CH shoulders.ConclusionThis study presents anatomic differences between African and European glenohumeral articulating surfaces. The results suggest that the glenohumeral geometry is both gender and population specific, and future joint replacements may be designed to address these differences.

Impact of infancy duration on adult size in 22 subsistence‐based societies

Humans evolved to withstand harsh environments by adaptively decreasing their body size. Thus, adaptation to a hostile environment defers the infancy-childhood transition age (ICT), culminating in short stature. In natural-fertility human societies, this transition is associated with weaning from breastfeeding and the mother's new pregnancy. We therefore used the interbirth interval (IBI) as a surrogate for the ICT. We hypothesized that long IBI will be associated with smaller body size. The sample used is 22 subsistence-based societies of foragers, horticulturalists and pastorals from Africa, South America, Australia and Southeast Asia. The IBI correlated negatively with the average adult bodyweight but not height. After correction for 'pubertal spurt takeoff' and 'weight at age 5', the IBI explains 81% of 'average adult weight' variability. This inter-population study confirms that body weight is adaptively smaller in hostile environments and suggests that the selected trait for this adaptation is the ICT age.

Inferences about antennal phenotype: the “ Triatoma maculata complex” (Hemiptera: Triatominae) is valid?

The “ Triatoma maculata complex” is presently formed by two epidemiologically important species of Triatominae, Triatoma maculata and Triatoma pseudomaculata, which share morphologic and chromatic characteristics. In order to clarify the systematic status and infer the evolutionary relationships of these vectors of Chagas disease, we performed a comparative analysis of their antennal phenotype, taking also into account Triatoma wygodzinskyi, a possible sister species. The comparison was based on sensilla arrays on the three distal segments of the antenna. Our results show a close similarity between T. pseudomaculata and T. wygodzinskyi antennal phenotypes, and significant differences with T. maculata. The inter-population study reinforces the idea that T. pseudomaculata (arboricolous species) and T. wygodzinskyi (rupicolous species) would originate from a common ancestor.

The Population Genetic Structure of Tetranychus kanzawai Kishida (Acari: Tetranychidae) in Northern Hokkaido, Japan, as Estimated Using Microsatellite Polymorphism

We examined the genetic structure of Tetranychus kanzawai populations occurring in northern Hokkaido, Japan, and gene flow among the populations using microsatellite DNA markers. Our intrapopulation analysis found that the genetic diversity within each population was small, whereas our interpopulation study revealed that the populations were genetically isolated, though a few population pairs were genetically close. The results show that in this study area, T. kanzawai maintained its population mainly by inbreeding, without frequent interpopulation gene exchange. As a consequence, the genetic diversity within each population was small but the genetic differentiation among populations was large.

Interpopulation study of three Artemia strains from South India based on cyst membrane proteins

Isolated embryonic membranes (i.e. the outer cuticular membrane, the fibrous layer, the inner cuticular membrane and the hatching membrane) of a bisexual and two parthenogenetic strains from South India were examined using sodium dodecyl-sulphate polyacrylamide gel electrophoresis. Interpopulation comparison of the protein patterns revealed variations in the major polypeptides between the three populations. Repeated analyses of the embryonic membrane protein pattern of the same population resulted in the same banding pattern suggesting that the method is reproducible. These differences might be used as markers for identification of different Artemia strains.

LDL heterogeneity revisited: lesson for the metabolic syndrome from a new interpopulation study?

LDL heterogeneity revisited: lesson for the metabolic syndrome from a new interpopulation study?

An Interpopulation Study of the Essential Oils of Various Parts of Crithmum maritimum L. Growing in Amorgos Island, Greece

The composition of the essential oil obtained from different parts of Crithmum muritimum L., growing in Amorgos island (Greece) and their interpopulation variability were investigated by GC and GUMS. The yield of the essential oil from various parts of the plants in the examined populations, varied from 0.08-0.99%. Monoterpenes constituted the more important portion of the oil while a few sesquiterpene hydrocarbons were detected in small amounts. The major compounds detected in all cases were p-cyrnene (0.8-15.8%), methyl thymol (4.4-41.0%), terpinen-4-01 (3.9-16.0%), sabinene (1.1-24.7%), β-phellandrene (0-10.3%), γ-terpinene (6.9-28.6%), or even dillapiole (0-48.8%) in one case. The results obtained from GUMS analysis of the oils were subjected to multivariate analysis (cluster analysis).

An interpopulation study of the essential oils of Cistus parviflorus L. growing in Crete (Greece)

The composition of the essential oils of nine populations of Cistus parviflorus L., from Crete (Greece) and their interpopulation variability, were investigated by GC-MS. 114 compounds were identified representing an average of 85-96% of oil composition. Labdane diterpenes were detected and identified in the essential oils of Cistus parviflorus L. for the first time. The results obtained from GC-MS analysis of the volatile oils were submitted to principal component and chemometric cluster analysis. Two main chemotypes (clusters) were differentiated; the first of West Crete and the second of East Crete. Carvacrol, caryophyllene oxide, alpha-epi-cadinol, abietatriene, 4-epi-dehydroabietol, dehydro abietol, cis-ferruginol and manoyl oxide mixture of isomers are the main constituents, while oxygenated sesquiterpenes as well as diterpenes have been found in high percentage composition.

Methodological Considerations on Intra- versus Interpopulation Correlation Studies

Epidemiological studies on the diet-health relationship have frequently resulted in confusing controversies rather than in clear and consistent findings. As an illustration of this phenomenon the relationship between dietary cholesterol and coronary heart disease (CHD) is used in this presentation. The epidemiological evidence favoring a strong and causal relationship between dietary cholesterol, serum lipids and CHD relied until some years ago largely on studies between populations. However these studies are more susceptible to confounding error. Therefore epidemiological studies have been conducted within populations looking into the relationship between dietary cholesterol, CHD risk and CHD frequency on the individual level. Until recently no consistent association had been observed between dietary cholesterol and serum total cholesterol levels or between dietary cholesterol and CHD mortality in homogeneous groups of individuals; this relates probably to methodological problems in measuring the dietary variable with sufficient precision. More recent studies using a more precise dietary methodology and a prospective study design over longer time periods result in observations that are more in line with the interpopulation study observations. Besides epidemiological evidence it is necessary to compare these findings with those from experimental work and from clinical studies. This approach has the best chance to separate ecological fallacy from real existing associations between diet and health.