Identification of a novel 15.5 kb <Emphasis Type="Italic">SHOX</Emphasis> deletion associated with marked intrafamilial phenotypic variability and analysis of its molecular origin

Haploinsufficiency of the short stature homeobox contaning SHOX gene has been shown to result in a spectrum of phenotypes ranging from Leri–Weill dyschondrosteosis (LWD) at the more severe end to SHOX-related short stature at the milder end of the spectrum. Most alterations are whole gene deletions, point mutations within the coding region, or microdeletions in its flanking sequences. Here, we present the clinical and molecular data as well as the potential molecular mechanism underlying a novel microdeletion, causing a variable SHOX-related haploinsufficiency disorder in a three-generation family. The phenotype resembles that of LWD in females, in males, however, the phenotypic expression is milder. The 15523-bp SHOX intragenic deletion, encompassing exons 3–6, was initially detected by array-CGH, followed by MLPA analysis. Sequencing of the breakpoints indicated an Alu recombination-mediated deletion (ARMD) as the potential causative mechanism.     

Coscinoderma sporadense sp.n. from the Aegean Sea with comments on Coscinoderma confragosum (Porifera, Dictyoceratida)

Coscinoderma sporadense sp.n. is described from shallow waters in the North Aegean. This is the first record of a Coscinoderma species from the Mediterranean. The new species is compared to the deep water East Atlantic Coscinoderma confragosum Poléjaeff, 1884, and clear differences between them are established. The status of the genus Coscinoderma is discussed.     

Sex chromosome variability outlines the pathway to the chromosomal evolution in Microtus thomasi (Rodentia, Arvicolinae)

The underground vole Microtus thomasi , a Balkan endemic, displays remarkable variability in sex chromosome size and morphology. In the present study, we demonstrate this variability in two of its chromosomal races with 2 n  = 44 (i.e. 'thomasi' and 'atticus') with the use of C-banding on a sample of 189 individuals from 50 localities of Greece. In 'thomasi', five different, acrocentric X chromosome variants (X₀–X₄) are described, which differ significantly in size, due to heterochromatin addition. Also, three Y chromosome variants are described (Y₀–Y₂), ranging in size from very small (Y₀) to large (Y₂). The 'atticus' race displays three subtelocentric variants of the X chromosome (X_st0–X_st2), which differ in arm length ratio and heterochromatin content. In Peloponnesus, males of this race exhibit Y₀ and Y₁, whereas, in Attiki (south-east Sterea Ellada), males carry the small metacentric, Y_m. Overall, there is a trend towards sex chromosome size increase in a south to north direction. We propose that the last glaciation must have restricted M. thomasi to a refugium in southern Peloponnesus. During post-glacial colonization, limited northward expansion of its distribution area must have been accompanied by consecutive heterochromatin addition, which is proven today by comparatively larger sex chromosomes in the northern populations of 'thomasi' and 'atticus' in Greece than in their southern populations.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 96 , 685–695.     

Phylogenetics and biogeography of the Balkan ‘sand gobies’ (Teleostei: Gobiidae): vulnerable species in need of taxonomic revision

Within the Atlantic–Mediterranean region, the ‘sand gobies’ are abundant and widespread, and play an important role in marine, brackish, and freshwater ecosystems. They include the smallest European freshwater fish, Economidichthys trichonis, which is threatened by habitat loss and pollution, as are several other sand gobies. Key to good conservation management is an accurate account of the number of evolutionary significant units. Nevertheless, many taxonomic and evolutionary questions remain unresolved within the clade, and molecular studies are lacking, especially in the Balkans. Using partial 12S and 16S mitochondrial ribosomal DNA sequences of 96 specimens of at least eight nominal species (both freshwater and marine populations), we assess species relationships and compare molecular and morphological data. The results obtained do not support the monophyly of Economidichthys, suggesting the perianal organ to be a shared adaptation to hole‐brooding rather than a synapomorphy, and urge for a taxonomic revision of Knipowitschia. The recently described Knipowitschia montenegrina seems to belong to a separate South‐East Adriatic lineage. Knipowitschia milleri, an alleged endemic of the Acheron River, and Knipowitschia cf. panizzae, are shown to be very closely related to other western Greek Knipowitschia populations, and appear conspecific. A distinct Macedonian–Thessalian lineage is formed by Knipowitschia thessala, whereas Knipowitschia caucasica appears as an eastern lineage, with populations in Thrace and the Aegean. The present study combines the phylogeny of a goby radiation with insights on the historical biogeography of the eastern Mediterranean, and identifies evolutionary units meriting conservation attention. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105 , 73–91.     

Promotion and inhibition by ethylene of chlorophyll degradation in orange fruits

The effect of ethylene concentration on chlorophyll destruction in orange (Citrus sinensis cV. Washington Navel) fruits was examined at 15 °C and 25 °C. The reflectance of the fruits at 680 nm was measured, and the results converted to chlorophyll concentrations through an empirically derived formula based on the Kubelka-Munk equation. In all ethylene treatments chlorophyll destruction was faster at 25 °C than at 15 °C and all ethylene concentrations tested increased the rate of loss at 25 °C. At 15 °C the highest rate of chlorophyll destruction was observed at 1 μl litre^-1 ethylene, while chlorophyll loss at 1250 μl litre^-1 was slower than in untreated fruits.     

Phylogenetic relationships of Atherina hepsetus and Atherina boyeri (Pisces: Atherinidae) populations from Greece, based on mtDNA sequences

The genetic divergence and the phylogenetic relationships of six Atherina boyeri (freshwater and marine origin) and five Atherina hepsetus populations from Greece were investigated using partial sequence analysis of 12s rRNA, 16s rRNA and control region mtDNA segments. Three different well divergent groups were revealed; the first one includes A. boyeri populations living in the sea, the second includes A. boyeri populations living in the lakes and lagoons whereas the third one includes all A. hepsetus populations. Fifty-seven different haplotypes were detected among the populations studied. In all three mtDNA segments examined, sequence analysis revealed the existence of fixed haplotypic differences discriminating A. boyeri populations inhabiting the lagoon and the lakes from both the coastal A. boyeri and the A. hepsetus populations. The genetic divergence values estimated between coastal (marine) A. boyeri populations and those living in the lagoon and the lakes are of the same order of magnitude as those observed among coastal A. boyeri and A. hepsetus populations. The results obtained by different phylogenetic methods were identical. The deep sequence divergence with the fixed different haplotypes observed suggests the occurrence of a cryptic or sibling species within A. boyeri complex.  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 92 , 151–161.     

Molecular taxonomy and phylogeography of Miniopterus schreibersii (Kuhl, 1817) (Chiroptera: Vespertilionidae), in the Eurasian transition

Miniopterus schreibersii is a polytypic bat species, with one of the widest distribution ranges among the mammals. We studied the genetic differentiation and taxonomy of this species in the transition zone between south-eastern Europe and Anatolia (in Asia), where two subspecies have been described. The results indicated a sharp genetic break between the samples from western Anatolia and south-eastern Europe and those of eastern Anatolia. In addition, the samples from western Anatolia and south-eastern Europe were seen to be reciprocally monophyletic, although the differentiation was less drastic. These patterns of genetic differentiation suggest the presence of two distinct groups within the M. schreibersii complex in the region, concordant with previous subspecific recognition. The cause of this genetic break is most likely differentiation in separate glacial refugia followed by secondary contact. However, more samples are needed to assess whether these represent different species, as well as to understand more clearly the causes of this differentiation.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 87 , 577–582.