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During the past twenty years, a number of molecular analyses have been performed to determine the evolutionary relationships of Onchocercidae, a family of filarial nematodes encompassing several species of medical or veterinary importance. However, opportunities for broad taxonomic sampling have been scarce, and analyses were based mainly on 12S rDNA and coxI gene sequences. While being suitable for species differentiation, these mitochondrial genes cannot be used to infer phylogenetic hypotheses at higher taxonomic levels. In the present study, 48 species, representing seven of eight subfamilies within the Onchocercidae, were sampled and sequences of seven gene loci (nuclear and mitochondrial) analysed, resulting in the hitherto largest molecular phylogenetic investigation into this family. Although our data support the current hypothesis that the Oswaldofilariinae, Waltonellinae and Icosiellinae subfamilies separated early from the remaining onchocercids, Setariinae was recovered as a well separated clade. Dirofilaria, Loxodontofilaria and Onchocerca constituted a strongly supported clade despite belonging to different subfamilies (Onchocercinae and Dirofilariinae). Finally, the separation between Splendidofilariinae, Dirofilariinae and Onchocercinae will have to be reconsidered.

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Abstract:Despite the small sample size the diversity of Rhabdias Stiles et Hassall, 1905 from anurans in the Afrotropical region was found to be high. Four species were collected from four localities, one in South Africa, two on Cameroonese mountains and one in Madagascar: Rhabdias picardiae sp. n. from the bufonid Amietophrynus gutturalis (Power); Rhabdias ohlerae sp. n. and Rhabdias tanyai sp. n. from the arthroleptids Leptopelis brevirostris (Werner) and Astylosternus rheophilus Amiet, respectively; and Rhabdias vencesi sp. n. from the mantellid Boophis madagascariensis (Peters). Distinctive characters between these species are numerous and obvious, based on body size, shape and size of the buccal capsule, arrangement of head papillae, and shape and size of the oesophagus and intestinal apex. Molecular data based on 500 bp of 12S rDNA and 600 bp of coxI of three of the four species are presented. Rhabdias vencesi resembles Rhabdias madagascariensis Chabaud, Brygoo et Petter, 1961 from an African ptychadenid introduced on Madagascar, but differs in body size and head morphology. The remaining new species are clearly distinct from those previously known from Afrotropical anurans. Outside the Afrotropics, some Rhabdias species present characters similar to those observed in the new species, but they all differ in various other characters. No clear correlation was seen between Rhabdias species and families of anuran hosts in this region. However, the narrow buccal capsule seen in Rhabdias species from Afrotropical lissamphibians opposes them to the majority of Rhabdias parasitic in chamaeleonids. Furthermore, the infective larva of R. vencesi has a conical pointed tail, while those of Rhabdias from chameleons have a rounded tail tip ornated with a few buds.

Wolbachia are alpha-proteobacteria symbionts infecting a large range of arthropod species and two different families of nematodes. Interestingly, these endosymbionts are able to induce diverse phenotypes in their hosts: they are reproductive parasites within many arthropods, nutritional mutualists within some insects and obligate mutualists within their filarial nematode hosts. Defining Wolbachia ‘species’ is controversial and so they are commonly classified into 17 different phylogenetic lineages, termed supergroups, named A–F, H–Q and S. However, available genomic data remain limited and not representative of the full Wolbachia diversity; indeed, of the 24 complete genomes and 55 draft genomes of Wolbachia available to date, 84 % belong to supergroups A and B, exclusively composed of Wolbachia from arthropods. For the current study, we took advantage of a recently developed DNA-enrichment method to produce four complete genomes and two draft genomes of Wolbachia from filarial nematodes. Two complete genomes, wCtub and wDcau, are the smallest Wolbachia genomes sequenced to date (863 988 bp and 863 427 bp, respectively), as well as the first genomes representing supergroup J. These genomes confirm the validity of this supergroup, a controversial clade due to weaknesses of the multilocus sequence typing approach. We also produced the first draft Wolbachia genome from a supergroup F filarial nematode representative (wMhie), two genomes from supergroup D (wLsig and wLbra) and the complete genome of wDimm from supergroup C. Our new data confirm the paradigm of smaller Wolbachia genomes from filarial nematodes containing low levels of transposable elements and the absence of intact bacteriophage sequences, unlike many Wolbachia from arthropods, where both are more abundant. However, we observe differences among the Wolbachia genomes from filarial nematodes: no global co-evolutionary pattern, strong synteny between supergroup C and supergroup J Wolbachia, and more transposable elements observed in supergroup D Wolbachia compared to the other supergroups. Metabolic pathway analysis indicates several highly conserved pathways (haem and nucleotide biosynthesis, for example) as opposed to more variable pathways, such as vitamin B biosynthesis, which might be specific to certain host–symbiont associations. Overall, there appears to be no single Wolbachia –filarial nematode pattern of co-evolution or symbiotic relationship.

Background/Aims: Prostate cancer represents the cancer with the highest worldwide prevalence in men. Chromosome 8p23 has shown suggestive genetic linkage to early-onset familial prostate cancer and is frequently deleted in cancer cells of the urogenital tract. Within this locus some β-defensin genes (among them DEFB4, DEFB103, DEFB104) are localized, which are arranged in a gene cluster shown to exhibit an extensive copy number variation in the population. This structural variation considerably hampers genetic studies. In a new approach considering both sequence as well as copy number variations we aimed to compare the defensin locus at 8p23 in prostate cancer patients and controls. Methods: We apply PCR/cloning-based haplotyping and high-throughput copy number determination methods which allow assessment of both individual haplotypes and gene copy numbers not accessible to conventional SNP-based genotyping. Results: We demonstrate association of four common DEFB104 haplotypes with the risk of prostate cancer in two independent patient cohorts. Moreover, we show that high copy numbers (>9) of the defensin gene cluster are significantly underrepresented in both patient samples. Conclusions: Our findings imply a role of the antibacterial defensins in prostate cancerogenesis qualifying distinct gene variants and copy numbers as potential tumor markers.

Based on material deposited in museum collections, twelve species within Mansonella sensu lato were examined and their descriptions amended. Based on additional morphological details, the erection of the new monotypic subgenus Filyamagutia Bain & Uni for M. (F.) akitensis (Uni, 1983), and the new combination M. (Pseudolitomosa) musasabi (Yamaguti, 1941) Bain & Uni are proposed. A new subspecies, M. (Tetrapetalonema) atelensis amazonae Bain & Guerrero is described and a key to the seven subgenera of Mansonella is provided. Furthermore, the elevation of Sandnema to full genus rank comprising the two species S. digitatum (Chandler, 1929) n. comb. and S. sunci (Sandground, 1933) n. comb., is proposed. Host and geographic records for the species of Mansonella and Sandnema are included.

The helminths of 15 Helmeted Guineafowls were collected in the north of Limpopo Province, South Africa. A total of 11 cestode, ten nematode and a single acanthocephalan species were present. Species richness ranged from 8 to 16 species per host, and nine core and nine secondary species accounted for 40.9% of the component parasite community. The remaining 18.2% comprised satellite species. Core species represented 91% of all the worms present. Individual intensities ranged from 66 to 2 724 per host and overdispersion was pronounced. There were no significant differences regarding the abundance and species richness between male and female hosts. The number of component species and overall abundance did not differ significantly between juvenile and adult hosts, but Cyrnea parroti was significantly more abundant, and the prevalence of Hadjelia truncata was higher in young birds than in adults. In contrast, Gongylonema congolense and Porogynia paronai were absent in juveniles, but had a prevalence of 60% and 70%, respectively, in adults. Pairwise Spearman's rank correlation yielded one positive and 10 negative significant species correlations. A single trematode, Dicrocoelium macrostomum, was collected from five of nine guineafowls, but was not included in the helminth community study.