Genome-wide association analysis of genetic generalized epilepsies implicates susceptibility loci at 1q43, 2p16.1, 2q22.3 and 17q21.32

Genetic generalized epilepsies (GGEs) have a lifetime prevalence of 0.3% and account for 20-30% of all epilepsies. Despite their high heritability of 80%, the genetic factors predisposing to GGEs remain elusive. To identify susceptibility variants shared across common GGE syndromes, we carried out a two-stage genome-wide association study (GWAS) including 3020 patients with GGEs and 3954 controls of European ancestry. To dissect out syndrome-related variants, we also explored two distinct GGE subgroups comprising 1434 patients with genetic absence epilepsies (GAEs) and 1134 patients with juvenile myoclonic epilepsy (JME). Joint Stage-1 and 2 analyses revealed genome-wide significant associations for GGEs at 2p16.1 (rs13026414, Pmeta = 2.5 × 10−9, OR[T] = 0.81) and 17q21.32 (rs72823592, Pmeta = 9.3 × 10−9, OR[A] = 0.77). The search for syndrome-related susceptibility alleles identified significant associations for GAEs at 2q22.3 (rs10496964, Pmeta = 9.1 × 10−9, OR[T] = 0.68) and at 1q43 for JME (rs12059546, Pmeta = 4.1 × 10−8, OR[G] = 1.42). Suggestive evidence for an association with GGEs was found in the region 2q24.3 (rs11890028, Pmeta = 4.0 × 10−6) nearby the SCN1A gene, which is currently the gene with the largest number of known epilepsy-related mutations. The associated regions harbor high-ranking candidate genes: CHRM3 at 1q43, VRK2 at 2p16.1, ZEB2 at 2q22.3, SCN1A at 2q24.3 and PNPO at 17q21.32. Further replication efforts are necessary to elucidate whether these positional candidate genes contribute to the heritability of the common GGE syndrome

Brittle stars (Echinodermata: Ophiuroidea) in the German Bight (North Sea) species diversity during the past 130 years

In this study, an overview of the current species composition of ophiuroids off Helgoland, German Bight (North Sea) is given. In addition, abundance and distribution of ophiuroids on different types of soft bottom sediments taken by van Veen grab samples around Helgoland was recorded. Literature was reviewed in order to outline the diversity of ophiuroid species over the past 130 years in the inner German Bight. In historical literature, quantitative references often apply to verbal descriptions and thus make comparisons to modern data and assessment of possible changes in abundance rather subjective.In total, six ophiuroid species were identified off Helgoland: Acrocnida brachiata (Montagu, 1804), Amphiura filiformis (M?ller, 1776), Amphipholis squamata (Delle Chiaje, 1829), Ophiothrix fragilis (Abildgaard, 1789), Ophiura albida Forbes, 1839 and Ophiura ophiura (Linnaeus, 1758). The species found in this study had also been reported by previous investigators and are regarded as ?common? species in the German Bight. Occasional findings in this area refer to Amphiura chiajei Forbes, 1843, Ophiopholis aculeata (Linnaeus, 1767), Ophiocten affinis (L?tken, 1858) and Ophiura sarsii L?tken, 1858, which are regarded here as ?rare? species. These findings, however, do not indicate sustainable changes in the species diversity over time.Apart from A. brachiata, a newcomer in the 1970s, findings of the common species mentioned above can be dated back to 1875. Therefore, a fairly stable composition of brittle stars is represented in the inner German Bight during the past 130 years