Epidemiology and genetics of endemic goiter. II. Genetic aspects

Complex genetic models and segregation analysis were applied to family data obtained in a hyperendemic goiter area in Brazil. The single locus and Falconer's models did not fit the data. Edward's model showed convergency, but statistical concordance has not been obtained. Although the genetic load model explains statistically the family data, it would be hard to imagine that endemic goiter could be explained by a model where synergism among genetic and environmental factors is not assumed.

Epidemiology and genetics of endemic goiter. I. Epidemiological aspects

This study dealt with approximately 2,000 children and their parents living in a hyperendemic goiter area in Central Brazil, which is bounded by the jungle to the north and by a large plain to the south. The determination of goiter was made according to the methods and classification adopted by WHO. Conspicuous forms of goiter were found in 41% of the children examined. Multiple linear regression analysis showed an increase with age in the frequency of goiter in both sexes. Although data from the literature show that Mulattoes and Negroes have statistically higher frequencies of goiter than do Whites, our multiple linear regression analysis revealed no evidence for an effect of race on the endemism. There was no significant association with socioeconomic level. The presence of goiter in parents was shown to be statistically associated with its occurrence in the children.

Biologic and genetics aspects of chagas disease at endemic areas

The etiologic agent of Chagas Disease is the Trypanosoma cruzi, transmitted through blood-sucking insect vectors of the Triatominae subfamily, representing one of the most serious public health concerns in Latin America. There are geographic variations in the prevalence of clinical forms and morbidity of Chagas disease, likely due to genetic variation of the T. cruzi and the host genetic and environmental features. Increasing evidence has supported that inflammatory cytokines and chemokines are responsible for the generation of the inflammatory infiltrate and tissue damage. Moreover, genetic polymorphisms, protein expression levels, and genomic imbalances are associated with disease progression. This paper discusses these key aspects. Large surveys were carried out in Brazil and served as baseline for definition of the control measures adopted. However, Chagas disease is still active, and aspects such as host-parasite interactions, genetic mechanisms of cellular interaction, genetic variability, and tropism need further investigations in the attempt to eradicate the disease. Copyright 2012 Marilanda Ferreira Bellini et al.

A precautionary tale when describing species in a world of invaders: Morphology, coloration and genetics demonstrate that Lysmata rauli is not a new species endemic to Brazil but a junior synonym of the Indo-Pacific L. vittata

The objective of this study was to investigate morphological variation in traits of systematic relevance and the phylogenetic position, ecology, and reproductive biology of the shrimp Lysmata rauli Laubenheimer and Rhyne, 2010 (Caridea: Hippolytidae), described based only on a single specimen collected in Salvador, Bahia, Brazil. We analyzed a total of 89 specimens from Camamu Bay, Bahia (n = 88) and from S3o Vicente estuary, São Paulo (n = 1). Considerable morphological variation was detected in the rostral spine series, number of segments on the carpus and merus of pereiopod 2, number of spiniform setae on the ventrolateral margin of merus and on the ventral margin of propodus of pereiopods 3-5. Importantly, L rauli can be distinguished neither using morphology, nor coloration from the Indo-Pacific L. vittata (Stimpson, 1860). Furthermore, molecular phylogenetic analyses (using the 16S mt DNA fragment) did not reveal any considerable genetic dissimilarities between L rauli and L vittata. Thus, our results clearly indicate that L rauli is not a new species but a junior synonym of L vittata. The high density observed within the structures of oyster farming indicates that the invasive L vittata lives in crowds in Brazil. The studied population was composed of males, hermaphrodites, and transitional individuals (having characteristics of males and hermaphrodites). The above information suggests that L rauli is a protandric simultaneous hermaphrodite, as it has been observed in all species of Lysmata that have been investigated. Lysmata vittata has invaded the southwestern Atlantic and is present in Bahia, Rio de Janeiro and S3o Paulo, Brazil. © The Crustacean Society, 2013. Published by Brill NV, Leiden.

Luminescent Systems for Genomics and Proteomics

The present PhD project was focused on the development of new tools and methods for luminescence-based techniques. In particular, the ultimate goal was to present substantial improvements to the currently available technologies for both research and diagnostic in the fields of biology, proteomics and genomics. Different aspects and problems were investigated, requiring different strategies and approaches. The whole work was thus divided into separate chapters, each based on the study of one specific aspect of luminescence: Chemiluminescence, Fluorescence and Electrochemiluminescence. CHAPTER 1, Chemiluminescence The work on luminol-enhancer solution lead to a new luminol solution formulation with 1 order of magnitude lower detection limit for HRP. This technology was patented with Cyanagen brand and is now sold worldwide for Western Blot and ELISA applications. CHAPTER 2, Fluorescescence The work on dyed-doped silica nanoparticles is marking a new milestone in the development of nanotechnologies for biological applications. While the project is still in progress, preliminary studies on model structures are leading to very promising results. The improved brightness of these nano-sized objects, their simple synthesis and handling, their low toxicity will soon turn them, we strongly believe, into a new generation of fluorescent labels for many applications. CHAPTER 3, Electrochemiluminescence The work on electrochemiluminescence produced interesting results that can potentially turn into great improvements from an analytical point of view. Ru(bpy)3 derivatives were employed both for on-chip microarray (Chapter 3.1) and for microscopic imaging applications (Chapter 3.2). The development of these new techniques is still under investigation, but the obtained results confirm the possibility to achieve the final goal. Furthermore the development of new ECL-active species (Chapter 3.3, 3.4, 3.5) and their use in these applications can significantly improve overall performances, thus helping to spread ECL as powerful analytical tool for routinary techniques. To conclude, the results obtained are of strong value to largely increase the sensitivity of luminescence techniques, thus fulfilling the expectation we had at the beginning of this research work.

Functional Genomics and Cell Biology of the Dolphin (Tursiops runcatus): Establishment of Novel Molecular Tools to Study Marine Mammals in Changing Environments

The dolphin (Tursiops truncatus) is a mammal that is adapted to life in a totally aquatic environment. Despite the popularity and even iconic status of the dolphin, our knowledge of its physiology, its unique adaptations and the effects on it of environmental stressors are limited. One approach to improve this limited understanding is the implementation of established cellular and molecular methods to provide sensitive and insightful information for dolphin biology. We initiated our studies with the analysis of wild dolphin peripheral blood leukocytes, which have the potential to be informative of the animal’s global immune status. Transcriptomic profiles from almost 200 individual samples were analyzed using a newly developed species-specific microarray to assess its value as a prognostic and diagnostic tool. Functional genomics analyses were informative of stress-induced gene expression profiles and also of geographical location specific transcriptomic signatures, determined by the interaction of genetic, disease and environmental factors. We have developed quantitative metrics to unambiguously characterize the phenotypic properties of dolphin cells in culture. These quantitative metrics can provide identifiable characteristics and baseline data which will enable identification of changes in the cells due to time in culture. We have also developed a novel protocol to isolate primary cultures from cryopreserved tissue of stranded marine mammals, establishing a tissue (and cell) biorepository, a new approach that can provide a solution to the limited availability of samples. The work presented represents the development and application of tools for the study of the biology, health and physiology of the dolphin, and establishes their relevance for future studies of the impact on the dolphin of environmental infection and stress.

Comparative genomics and phylogenetics of the vertebrate CYP3 family

CYP3A verstoffwechselt mehr als 50% aller gegenwärtig in der Therapie eingesetzten Wirkstoffe, die häufig an klinisch relevanten Arzneimitttel-Wechselwirkungen beteiligt sind. Das Verständnis über die Bedeutung und die Regulation von einzelnen CYP3A Genen in der Pharmakologie und Physiologie ist unvollständig. Wir untersuchten die Evolution des CYP3 Genlokus über einen Zeitraum von 450 Millionen Jahre mittels genomischer Sequenzen von 16 Tierarten. Neue CYP3 Unterfamilien (CYP3B, C und D) entstanden über eine beschleunigte Evolution aus CYP3A Vorstufen von Clupeocephala Spezies. Ausgeprägte funktionelle Unterschiede traten zwischen CYP3A in Säugern und Clupeocephala CYP3 auf. Alle amnioten CYP3A Gene entwickelten sich aus zwei CYP3A Urgenen. Aufgrund der Entstehung von Säugern mit Plazenta ging eines von ihnen verloren während das andere eine neue genomische Umgebung infolge einer Translokation erlangte. In Primaten unterzog sich CYP3A mit mehreren Genduplikationen, Deletionen, Pseudogenisierung und Genkonversionen einer raschen evolutionären Veränderung. Die Entwicklung von CYP3A in Schmalnasenaffen (Alte Welt Affen, große Menschenaffen und Menschen) unterschieden sich wesentlich von Neue Welt Primaten (z.B. gewöhnlichen Krallenaffen) und Feuchtnasenaffen (z.B. Galago). Stellvertretend für die CYP3A Protein-codierende Sequenz entdeckten wir zwei frühe Episoden von besonders starker positiver Selektion: (1) auf CYP3A7 in der frühen hominoiden Evolution, welche im fetalen Zeitraum von einer Einschränkung der hepatischen Expression begleitet war, und (2) auf humanes CYP3A4 im Anschluss an die Teilung der Abstammungslinie in Schimpansen und Mensch. In Übereinstimmung mit diesen Befunden beeinflussen drei von vier positiv ausgewählten Aminosäuren, die in früheren biochemischen CYP3A Studien untersucht wurden, die Aktivität und Regioselektivität. Es ist somit naheliegend, dass CYP3A7 und CYP3A4 katalytische Funktionen erworben haben können, die besonders wichtig waren für die Evolution von Hominoiden und Menschen. Die Charakterisierung von CYP3A Promotoren in Primaten zeigte eine Anreicherung von ER6 Elementen in CYP3A Promotoren von Primaten und einen Trend in Richtung Erhöhung der ER6 Enstehung entlang den Abstammungslinien, die zu humanen und Schimpansen CYP3A4 führten. Die steigende Anzahl an ER6 Elementen kann durch die ausgeprägte CYP3A4 Induzierbarkeit und Expressionsvariabilität im Menschen verursacht sein.

Landscape ecology and genetics of the wolf in Italy

This PhD Thesis includes five main parts on diverse topics. The first two parts deal with the trophic ecology of wolves in Italy consequently to a recent increase of wild ungulates abundance. Data on wolf diet across time highlighted how wild ungulates are important food resource for wolves in Italy. Increasing wolf population, increasing numbers of wild ungulates and decreasing livestock consume are mitigating wolf-man conflicts in Italy in the near future. In the third part, non-invasive genetic sampling techniques were used to obtain genotypes and genders of about 400 wolves. Thus, wolf packs were genetically reconstructed using diverse population genetic and parentage software. Combining the results on pack structure and genetic relatedness with sampling locations, home ranges of wolf packs and dispersal patterns were identified. These results, particularly important for the conservation management of wolves in Italy, illustrated detailed information that can be retrieved from genetic identification of individuals. In the fourth part, wolf locations were combined with environmental information obtained as GIS-layers. Modern species distribution models (niche models) were applied to infer potential wolf distribution and predation risk. From the resulting distribution maps, information pastures with the highest risk of depredation were derived. This is particularly relevant as it allows identifying those areas under danger of carnivore attack on livestock. Finally, in the fifth part, habitat suitability models were combined with landscape genetic analysis. On one side landscape genetic analyses on the Italian wolves provided new information on the dynamics and connectivity of the population and, on the other side, a profound analysis of the effects that habitat suitability methods had on the parameterization of landscape genetic analyses was carried out to contributed significantly to landscape genetic theory.

Large deletions in the CFTR gene: clinics and genetics in Swiss patients with CF

Cystic fibrosis (CF) is the most common life-shortening autosomal recessive disorder in Caucasians, and is associated with at least one mutation on each CF transmembrane conductance regulator (CFTR) allele. Some patients, however, with only one identifiable point mutation carry on the other allele, a large deletion that is not detected by conventional screening methods. The overall frequency of large deletions in patients with CF is estimated to be 1-3%. Using the CFTR Multiplex Ligation dependent Probe Amplification Kit (MRC-Holland, Amsterdam, Netherlands) that allows the exact detection of copy numbers from all 27 exons in the CFTR gene, we screened 50 patients with only one identified mutation for large deletions in the CFTR gene. Each detected deletion was confirmed using our real-time polymerase chain reaction (PCR) assay and deletion-specific PCR reactions using junction fragment primers. We detected large deletions in eight patients (16%). These eight CF alleles belong to four different deletion types (CFTRindel2, CFTRdele14b-17b, CFTRdele17a-17b and CFTRdele 2-9) whereof the last is novel. Comparing detailed clinical data of all these patients with CF and the molecular genetic findings, we were able to elaborate criteria for deletion screenings and possible genotype-phenotype associations. In conclusion, we agree with other authors that deletion screenings should be implemented in routine genetic diagnostics of CF.