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Objective: To evaluate the geoepidemiology of Sjögren's syndrome (SS) in Latin America. Methods: This was a three phase study in which original data from a Colombian cohort of patients with SS is presented, followed by a systematic review of Colombian and Latin American studies. Lastly, the geoepidemiology of SS in Latin America was assessed by comparing the clinical characteristics of the region with those of the rest of the world by means of a meta-analysis approach. Results: Data from 2970 patients from Latin America and 18019 patients from Europe, North America and Asia were analyzed. Colombian patients have a lower age at disease onset than those from other Latin American countries and a higher rate of positivity of antinuclear antibodies and rheumatoid factor. A significant difference in the proportion of female patients in Latin America compared with Europe and North America was observed. The spectrum of disease in Latin American was similar to North American patients, while strong differences were noticed between Latin American and European and Asian patients. Noteworthy, a paucity of reports including African and African-descendent patients was observed. Conclusions: The clinical spectrum of SS differs between countries and continents. Genetic differences relying upon ancestry could explain these findings. However, environmental factors have proven to be important determinants in the development of autoimmune diseases (i.e., autoimmune ecology). Thus, ancestry and the autoimmune ecology should be considered in studies aimed to evaluate the geoepidemiology of SS and other autoimmune diseases. © 2019 Société française de rhumatologie

En el presente trabajo, es estudiada la diversidad genética de tres poblaciones atribuidas a ecotipos de aguaymanto, Physalis peruaviana. Las tres poblaciones eran atribuidas a los ecotipos Agroandino (provincia de San Pablo), Celendino (provincia de Celendín) y Cajabamba (provincia de Cajabamba) del departamento de Cajamarca. Se realizó la cuantificación proteica y evaluó el polimorfismo de las proteínas de reserva seminal (SSPs) mediante electroforesis en gel de poliacrilamida denaturante (SDS-PAGE). Además, se identificaron características bioquímicas de las proteínas seminales en esta especie. No se hallaron diferencias entre las tres poblaciones basados en la cuantificación proteica. Las globulinas (82.4%) fueron la fracción mayoritaria seguida por las albuminas (13.9%), glutelinas (3.7%) y prolaminas (0.7%). Sólo las albuminas mostraron polimorfismo, hallándose 21 proteínas entre ~ 6.5 a ~45 kDa y tres perfiles electroforéticos diferentes, los cuales fueron compartidos entre las poblaciones. Se identificaron las leguminas y vicilinas en la fracción globulina. Las glutelinas mostraron proteínas de mismo peso molecular (PM) a las leguminas; y las prolaminas sólo una banda de bajo PM. La población de San Pablo fue completamente homogénea a diferencia de la población de Cajabamba que mostró la mayor diversidad genética seguida de Celendín. No fue posible diferenciar las poblaciones designadas como ecotipos Agroandino, Cajabamba y Celendino basados en el análisis de proteínas seminales. The genetic diversity of three populations designated as ecotypes of golden berry (Physalis peruaviana) is studied using protein quantification and polymorphism of seed storage proteins (SSPs) by denaturating polyacrylamide gel electrophoresis (SDS-PAGE). As well, biochemical characteristics of seed proteins were identified. The populations were from San Pablo province (Agroandino ecotype), Celendín province (Celendino ecotype) and Cajabamba province (Cajabamba ecotype), all from Cajamarca Department. There was not difference among the three populations based on protein quantification. Globulins (82.4%) were the majority fraction followed for albumins (13.9%), glutelins (3.7%) and prolamins (0.7%). Only albumins showed polymorphism, showing 21 proteins between ~6.5 to ~45 kDa and three different electrophoretic profiles, which were share among the three populations. Legumins and vicilins were identified in globulin fraction. Glutelins showed proteins of same molecular weight (MW) to legumins; and prolamins only a band of low MW. San Pablo province population (Agroandino ecotype) was completely uniform, while Cajabamba population showed higher genetic diversity followed by Celendin population. Our results shows that, based on seed proteins analyses is not possible to distinguish the three populations designated as Agroandino, Cajabamba and Celendino ecotypes.

Background Phylogenetic analysis strongly depends on evolutionary models. Most evolutionary models for estimating genetic differences and phylogenetic relationships do not treat gap sites in the alignment of sequences. Appropriately incorporating evolutionary information of sites containing insertions and deletions into genetic difference measures will be improve the accuracy of phylogenetic estimates. Results We introduced a new measure for estimating genetic differences, and presented P*R*O*P, a web application for performing phylogenetic analysis based on genetic difference considering the effect of gaps. As an example of phylogenetic analysis using P*R*O*P, we used complete p53 amino acid sequences of 31 organisms and illustrated that the genetic differences with and without information on sites containing gaps result in trees with different topologies. Conclusions P*R*O*P is available at https://www.rs.tus.ac.jp/bioinformatics/prop and the user can perform phylogenetic analysis by uploading sequence data on the website. The most distinctive feature of P*R*O*P is its genetic difference that is estimated without eliminating gap sites for alignment sequences, which helps users detect meaningful difference in an evolutionary process. The source code is available in GitHub: https://github.com/TUS-Satolab/PROP.

Barley is an important cereal crop worldwide. Its genetic transformation is now limited to very few cultivars because of the high genotype dependence of embryogenic callus. To reveal the key genes or factors controlling the callus induction and plantlet regeneration in barley, we compared the transcriptomic profiles of immature embryos of Golden Promise and ZU9, which differed dramatically in the efficiency of the genetic transformation. The samples were taken at 0, 5, 10 and 20 days of the culture, respectively. In total, 5386 up-regulated and 6257 down-regulated genes were identified in Golden Promise. Several genes, identified exclusively in GP callus, were selected for further investigation. These genes were mainly involved in protein metabolism, energy metabolism, stress response, detoxification and ubiquitin–proteasome. Four YUCCA flavin monooxygenases, one PIN-FORMED, one tryptophan aminotransferase related, three small auxin up RNA, three indole-3-acetic acid and one adenylate isopentenyl transferase, seven cytokinin oxidase/dehydrogenase, three Arabidopsis histidine kinase, three Arabidopsis histidine phosphotransfer protein, and one Arabidopsis response regulator were differentially expressed in the calli of the two barley genotypes, suggesting that biosynthesis, response and transport of auxin and cytokinin might be associated with cell reprogramming during callus induction. The current results provide insights into molecular mechanisms of callus induction at an early developmental stage and are helpful for optimizing the tissue culture system in barley.

Back Ground: Genetic polymorphisms of ABO and RhD blood group and Haptoglobin (HP) types have already been widely used to understand variation and population structure. The present study attempted to understand the variation and population structure on the basis of ABO and RhD blood group polymorphisms and Haptoglobin (HP) as serum protein polymorphism of four Tibeto-Burman speaker groups considered as aboriginal tribes of Tripura. Genetic studies on populations in north-east Indian have been performed less frequently than in the other parts of India, in spite of diversity among these populations. Aims and Objective: Best of the knowledge the present study is the first attempt on the variation and population genetic structure concerning the ABO, RhD and HP polymorphism of the four endogamous populations – Tripuri, Hrangkhawl, Rupini and Kolui tribal population of Tripura. Materials and Methods: Present study consisted of four hundred (400) participants 100 each from above mentioned population groups. ABO and RhD blood groups were done by antigen-antisera agglutination test and HP types were ascertained by Polyacrylamide Gel Electrophoresis (PAGE) following standard techniques. Allele frequencies and Fst were calculated by using standard method. Results: Examination on ABO blood group revealed higher O allele among the two groups Tripuri and Hrangkhawl followed by A and B alleles. Among the other two groups, Rupini and Kolui, revealed higher A allele and B allele respectively. Higher D allele frequency in the RHD Blood group system has been found for each of the population group. On the other hand, Serum protein marker - HP types demonstrated higher HP*2 allele frequency than HP*1 alleles. Calculated very low Fst value (0.02-0.08) of three polymorphic markers (ABO, RhD and HP) were suggestive for low differentiation among these groups, indicating less admixture and prevailing endogamous nature of these population. Conclusion: Very low Fst values of three polymorphic markers were suggestive for low differentiation among these groups, indicating least admixture and prevailing endogamous nature of these population. The overall genetic difference revealed highest distance between Tripuri and Hrangkhwal and least distance between Rupini and Kolui. Asian Journal of Medical Sciences Vol.9(3) 2018 46-49

Sürdürülebilirlik ancak sahip olunan genetikkaynakların kullanımı ve korunması ile mümkün olabilmektedir. Ak üçgül (Trifolium repens L.) ülkemizmeralarında, park ve bahçe alanlarında yaygın olarak bulunan çok yıllık birbaklagil yem bitkisi olmakla birlikte önemli bir genetik hazine kaynağıdır. Buçalışma ülkemizin yedi ilinden farklı yüksekliklerden toplanan ak üçgülpopulasyonlarının genetik farklılıklarının belirlenmesi amacıyla yürütülmüştür.Çalışma kapsamında toplanan on beş populasyonun genetik farklılıklarınınbelirlenmesinde altı adet Basit Dizi Tekrarları (SSR) markörü kullanılmıştır.Çalışma sonucunda 56 allel belirlenmiştir. Genetik akrabalıkların görülmesiamaçlı oluşturulan dendrogramda populasyonlar üç grup altında toplanmışlardır.Elde edilen sonuçlara göre, özellikle yüksek rakımlı duraklardan toplananpopulasyonların çoğunlukla aynı grup içerisinde yer aldıkları görülmüştür. Budurum toplanan örneklerdeki genetik çeşitliliğin coğrafi dağılım ilişkisiniortaya koymuştur. Sonuç olarak, ak üçgül ıslahı çalışmalarında gereklimateryali sağlama açısından ülkemizin zengin bir genetik çeşitliliğe sahipolduğu anlaşılmıştır., Sustainability can only be achieved through the use and protection of genetic resources. White clover (Trifoliumrepens L.), a perennial legume forage grass, is also an important genetic resource and widely found in grasslands, parks andgardens in many regions of Turkey. This study was conducted to determine the genetic diversity of white clover populationscollected from different altitudes on seven provinces of Turkey. Six Simple Sequence Repeats (SSR) molecular markerswere used to estimate genetic diversity in fifteen populations collected for the study. In the study, 56 alleles were detected.Populations were gouped as three clusters in the dendogram created to see genetic relationships. According to results,especially population collected from high altitudes were mostly in the same group. This revealed the interaction betweengeographical distribution and genetic diversity in the collected samples. As a result, it was understood that our country has arich genetic diversity to provide the necessary material in the white clover breeding.

Accurate estimates of genetic difference are required for research in evolutionary biology. Here we extend the Kimura two-parameter (K2P) model by considering gaps (insertions and/or deletions) and introduce a new measure for estimating genetic difference between two nucleotide sequences in terms of nucleotide changes that have occurred during the evolutionary process. Using the nuclear ribosomal DNA internal transcribed spacer 2 region from the genus Physalis, we demonstrate that species identification and phylogenetic studies strongly depend on evolutionary models. It is especially noteworthy that the use of different models affects the degree of overlap between intraspecific and interspecific genetic differences. We observe that the percentage of interspecific sequence pairs with values less than the maximum intraspecific genetic difference is 43.2% for the K2P model which is calculated by removing gap sites across all sequences, 22.7% for the K2P model which is calculated by removing gap sites for sequence pairs, and 16.9% for our model which is calculated without removing gap sites. Additionally, the numbers of sequence pairs with interspecific genetic differences of zero are 50 for the K2P model and 29 for our model. The genetic difference measure based on the K2P model, compared to our model, overestimates 21 sequence pairs that are not originally identical. These results indicate the importance of estimating genetic differences under the model of sequence evolution that includes insertions and deletions in addition to substitutions. Electronic supplementary material The online version of this article (10.1007/s00239-018-9885-1) contains supplementary material, which is available to authorized users.

Background Patients often ask oncologists how long a cancer has been present before causing symptoms or spreading to other organs. The evolutionary trajectory of cancers can be defined using phylogenetic approaches but lack of chronological references makes dating the exact onset of tumours very challenging. Patients and methods Here, we describe the case of a colorectal cancer (CRC) patient presenting with synchronous lung metastasis and metachronous thyroid, chest wall and urinary tract metastases over the course of 5 years. The chest wall metastasis was caused by needle tract seeding, implying a known time of onset. Using whole genome sequencing data from primary and metastatic sites we inferred the complete chronology of the cancer by exploiting the time of needle tract seeding as an in vivo ‘stopwatch’. This approach allowed us to follow the progression of the disease back in time, dating each ancestral node of the phylogenetic tree in the past history of the tumour. We used a Bayesian phylogenomic approach, which accounts for possible dynamic changes in mutational rate, to reconstruct the phylogenetic tree and effectively ‘carbon date’ the malignant progression. Results The primary colon cancer emerged between 5 and 8 years before the clinical diagnosis. The primary tumour metastasized to the lung and the thyroid within a year from its onset. The thyroid lesion presented as a tumour-to-tumour deposit within a benign Hurthle adenoma. Despite rapid metastatic progression from the primary tumour, the patient showed an indolent disease course. Primary cancer and metastases were microsatellite stable and displayed low chromosomal instability. Neo-antigen analysis suggested minimal immunogenicity. Conclusion Our data provide the first in vivo experimental evidence documenting the timing of metastatic progression in CRC and suggest that genomic instability might be more important than the metastatic potential of the primary cancer in dictating CRC fate.

Fusarium oxysporum f. melongenae is a major soil-borne pathogen of eggplant (Solanum melongena). ISSR and RAPD markers were used to characterize Fusarium oxysporum f. melongenae isolates collected from eggplant fields in southern Turkey. Those isolates were not pathogenic to tomato. Pathogens were identified by their morphology, and their identity was confirmed by PCR amplifi- cation using the specific primer PF02-3. The isolates were classified into groups on the basis of ISSR and RAPD fingerprints, which showed a level of genetic speci- ficity and diversity not previously identified in Fusarium oxysporum f. melongenae, suggesting that genetic differences are related to the pathogen in the Mediterranean region. The primers selected to characterize Fusarium oxysporum f. melongenae may be used to determine genetic differences and pathogen virulence. This study is the first to characterize eggplant F. oxysporum species using ISSR and RAPD.

Summary. Twenty-six avian infectious bronchitis (IB) viruses (IBV) were isolated from outbreaks in chickens in China between 1995 and 2004. They were characterized by comparison with twenty-six Chinese reference strains and five other IBV strains. Chinese IBVs, which were mainly nephropathogenic, were placed into seven genotypes. Fourteen Chinese IBV isolates were placed in genotype I, having small evolutionary distances from each other. Genotype II included 6 strains that were isolated in the 1990s in China. Genotype III consisted of eight Chinese isolates that showed close relationship with Korean IBV isolates. Another eight IBV isolates clustered in genotype IV and showed larger evolutionary distances. The Massachusetts serotype was present in China in 1990s and was in a separate genotype. Two isolates, HN99 and CK/CH/LHN/00I, which might be a reisolation of vaccine strains, clustered into genotype VI. Four Chinese IBV isolates formed another genotype and showed larger evolutionary distances from other Chinese IBV genotypes (genotype VII). IBVs in same genotypes showed more than 90% amino acid sequence similarities, whereas most of the viruses in different genotypes showed less than 90%. The results showed that IBVs in China came from genetic changes both in IBV populations that existed before the advent of vaccination and in the viruses that were introduced through live vaccines. IBVs showing various genetic differences are cocirculating in China.

Preaxial polydactyly is a common limb malformation in humans with variable clinical expression. Different types of triphalangeal thumb-preaxial polydactyly phenotypes were mapped to the chromosome 7q36 region. We studied a large Turkish family of 69 individuals, of whom 22 individuals were affected. In all, 11 affected family members were clinically and radiologically evaluated. All affected individuals had a triphalangeal thumb and a preaxial (hypoplastic) extra digit bilaterally, with minimal intrafamilial variation. No feet involvement was observed. Linkage and haplotype analyses using 20 informative meioses confirmed the 7q36 region contained the LIMBR1 gene. Maximum logarithm of the odds (LOD) scores were obtained with DNA markers D7S550 and D7S2423. We have further identified a novel C to T alteration at position 4909 bp in the critical zone of polarizing activity regulatory sequence (ZRS) region, in the intron 5, of the LMBR1 gene. One affected male with homozygous status and no phenotypic difference from affected family members with heterozygous status represented the first homozygote case of the triphalangeal thumb-preaxial polydactyly phenotype. © 2009 John Wiley & Sons A/S.

Background: Hypoxia-inducible factors (HIFs) are involved in adaptive and survival responses to hypoxic stress in mammals. In fish, very little is known about the functions of HIFs. Results: We have cloned and characterized two distinct HIF-alpha cDNAs - gcHIF-1alpha and gcHIF-4alpha - from the hypoxia-tolerant grass carp. The deduced gcHIF-1alpha protein is highly similar to the HIF-1alphas (57-68%) from various vertebrate species, while gcHIF-4alpha is a novel isoform, and shows an equivalent degree of amino acid identity (41-47%) to the HIF-1alpha, HIF-2alpha and HIF-3alpha proteins so far described. Parsimony analysis indicated that gcHIF-4alpha is most closely related to the HIF-3alpha proteins. Northern blot analysis showed that mRNA levels of gcHIF-1alpha and gcHIF-4alpha differ substantially under normoxic and hypoxic conditions, while Western blot studies demonstrated that the endogenous protein levels for both gcHIF-1alpha and gcHIF-4alpha are similarly responsive to hypoxia. Our findings suggest that both gcHIF-1alpha and gcHIF-4alpha are differentially regulated at the transcriptional and translational levels. HRE-luciferase reporter assays show that both proteins function as transcription activators and play distinct roles in modulating the hypoxic response in grass carp. Conclusion: There are at least two distinct HIF-alpha isoforms - gcHIF-1alpha and gcHIF-4alpha - in the hypoxia-tolerant grass carp, which are differentially expressed and regulated in different fish organs in response to hypoxic stress. Overall, the results suggest that unique molecular mechanisms operate through these two HIF-alpha isoforms, which underpin the hypoxic response in the hypoxia-tolerant grass carp. © 2006 Law et al; licensee BioMed Central Ltd., published_or_final_version

Prochlorococcus is a marine cyanobacterium that numerically dominates the mid-latitude oceans and is the smallest known oxygenic phototroph. Numerous isolates from diverse areas of the world's oceans have been studied and shown to be physiologically and genetically distinct. All isolates described thus far can be assigned to either a tightly clustered high-light (HL)-adapted clade, or a more divergent low-light (LL)-adapted group. The 16S rRNA sequences of the entire Prochlorococcus group differ by at most 3%, and the four initially published genomes revealed patterns of genetic differentiation that help explain physiological differences among the isolates. Here we describe the genomes of eight newly sequenced isolates and combine them with the first four genomes for a comprehensive analysis of the core (shared by all isolates) and flexible genes of the Prochlorococcus group, and the patterns of loss and gain of the flexible genes over the course of evolution. There are 1,273 genes that represent the core shared by all 12 genomes. They are apparently sufficient, according to metabolic reconstruction, to encode a functional cell. We describe a phylogeny for all 12 isolates by subjecting their complete proteomes to three different phylogenetic analyses. For each non-core gene, we used a maximum parsimony method to estimate which ancestor likely first acquired or lost each gene. Many of the genetic differences among isolates, especially for genes involved in outer membrane synthesis and nutrient transport, are found within the same clade. Nevertheless, we identified some genes defining HL and LL ecotypes, and clades within these broad ecotypes, helping to demonstrate the basis of HL and LL adaptations in Prochlorococcus. Furthermore, our estimates of gene gain events allow us to identify highly variable genomic islands that are not apparent through simple pairwise comparisons. These results emphasize the functional roles, especially those connected to outer membrane synthesis and transport that dominate the flexible genome and set it apart from the core. Besides identifying islands and demonstrating their role throughout the history of Prochlorococcus, reconstruction of past gene gains and losses shows that much of the variability exists at the “leaves of the tree,” between the most closely related strains. Finally, the identification of core and flexible genes from this 12-genome comparison is largely consistent with the relative frequency of Prochlorococcus genes found in global ocean metagenomic databases, further closing the gap between our understanding of these organisms in the lab and the wild., Author Summary Prochlorococcus—the most abundant photosynthetic microbe living in the vast, nutrient-poor areas of the ocean—is a major contributor to the global carbon cycle. Prochlorococcus is composed of closely related, physiologically distinct lineages whose differences enable the group as a whole to proliferate over a broad range of environmental conditions. We compare the genomes of 12 strains of Prochlorococcus representing its major lineages in order to identify genetic differences affecting the ecology of different lineages and their evolutionary origin. First, we identify the core genome: the 1,273 genes shared among all strains. This core set of genes encodes the essentials of a functional cell, enabling it to make living matter out of sunlight and carbon dioxide. We then create a genomic tree that maps the gain and loss of non-core genes in individual strains, showing that a striking number of genes are gained or lost even among the most closely related strains. We find that lost and gained genes commonly cluster in highly variable regions called genomic islands. The level of diversity among the non-core genes, and the number of new genes added with each new genome sequenced, suggest far more diversity to be discovered.

How often insecticide resistance mutations arise in natural insect populations is a fundamental question for understanding the evolution of resistance and also for modeling its spread. Moreover, the development of resistance is regarded as a favored model to study the molecular evolution of adaptive traits. In the malaria vector Anopheles gambiae two point mutations (L1014F and L1014S) in the voltage-gated sodium channel gene, that confer knockdown resistance (kdr) to DDT and pyrethroid insecticides, have been described. In order to determine whether resistance alleles result from single or multiple mutation events, genotyping of the kdr locus and partial sequencing of the upstream intron-1 was performed on a total of 288 A. gambiae S-form collected from 28 localities in 15 countries. Knockdown resistance alleles were found to be widespread in West Africa with co-occurrence of both 1014S and 1014F in West-Central localities. Differences in intron-1 haplotype composition suggest that kdr alleles may have arisen from at least four independent mutation events. Neutrality tests provided evidence for a selective sweep acting on this genomic region, particularly in West Africa. The frequency and distribution of these kdr haplotypes varied geographically, being influenced by an interplay between different mutational occurrences, gene flow and local selection. This has important practical implications for the management and sustainability of malaria vector control programs. Sí

The phylogenetic relationships of both African and South American electric fish orders are reviewed at their intra-ordinal level taking into consideration recent studies in which cladistic principles have been employed. Several concordant topologies emerge from the different data sets, but some unsettled issues still remain. From the studies available, a consensus topology has been suggested for the Mormyriformes and for the Gymnotiformes. Subsequently, the evolutionary relationships of these two electric fish clades are considered within each respective superorder, i.e. in relation to the other osteoglossomorph and ostariophysan orders. The inter-ordinal phylogenies are used as a framework to test the molecular clock hypothesis with two gene fragments of the mitochondrial genome. Gymnotiformes, Siluriformes and Characiformes are accumulating mutations at the same pace in relation to their respective outgroups, but for all the other combinations of sister clades tested the molecular clock can be statistically rejected. Fossil records are then surveyed and used to calibrate absolute rates of genetic differentiation for each main lineage (orders) of both osteoglossomorphs and ostariophysans. The most conserved regions (stems) of the 12S and 16S gene fragments used are evolving at an average rate of 0.123 % 106 years− 1 for the osteoglossomorphs and 0.137 % 106 years− 1 for the ostariophysans, with no significant difference between these two values. The rate of mutation in the loops, the faster-evolving segments, estimated for closely related electric fish taxa is 0.82 % 106 years− 1 for four Brienomyrus species and 1.01 % 106 years− 1 for the four eigenmanniid genera. When the entire molecule (loops + stems) is considered, the rate of mutation in both mormyriforms and gymnotiforms converges to a rounded value of 0.23 % 106 years− 1.