Metric variation in the postcanine teeth from Paşalar, Turkey

The coefficient of variation (CV) has frequently been used to evaluate variation in a morphologically homogeneous fossil assemblage and to make inferences about its species composition. Comparisons of coefficients of variation in single- and mixed-species assemblages have typically involved mixed-species assemblages made up of an equal number of data points from two or more different species, but in reality, a fossil assemblage may be biased in favor of one or more of the component species. In this paper, we evaluate the effects of unequal species composition in mixed-species assemblages on CV distributions by carrying out an extensive series of resampling experiments. The experiments were designed to replicate a paleontological situation in which the species affiliation of particular specimens is not known. We use this technique to explore the pattern of metric variation in the postcanine dental assemblage from the middle Miocene site of Pa?alar in a comparative context. The distributions of CVs from mixed assemblages that are heavily biased toward one species may be characterized by a greater range of CVs, increased skewing, and a tail of low values, but only heavily biased assemblages comprising species that differ markedly in size could be reliably identified on this basis. Evidence from the simulated CV distributions supports nonmetric evidence in indicating that the Pa?alar assemblage represents a heavily biased assemblage of two species that are similar in size but not entirely overlapping in the size distributions of their postcanine teeth.     

Modifier locus of the skeletal muscle involvement in Emery–Dreifuss muscular dystrophy

Autosomal dominant Emery–Dreifuss muscular dystrophy is caused by mutations in LMNA gene encoding lamins A and C. The disease is characterized by early onset joint contractures during childhood associated with humero-peroneal muscular wasting and weakness, and by the development of a cardiac disease in adulthood. Important intra-familial variability characterized by a wide range of age at onset of myopathic symptoms (AOMS) has been recurrently reported, suggesting the contribution of a modifier gene. Our objective was to identify a modifier locus of AOMS in relation with the LMNA mutation. To map the modifier locus, we genotyped 291 microsatellite markers in 59 individuals of a large French family, where 19 patients carrying the same LMNA mutation, exhibited wide range of AOMS. We performed Bayesian Markov Chain Monte Carlo-based joint segregation and linkage methods implemented in the Loki^© software, and detected a strong linkage signal on chromosome 2 between markers D2S143 and D2S2244 (211 cM) with a Bayes factor of 28.7 (empirical p value = 0.0032). The linked region harbours two main candidate genes, DES and MYL1 encoding desmin and light chain of myosin. Importantly, the impact of the genotype on the phenotype for this locus showed an overdominant effect with AOMS 2 years earlier for the homozygotes of the rare allele and 37 years earlier for the heterozygotes than the homozygotes for the common allele. These results provide important highlights for the natural history and for the physiopathology of Emery–Dreifuss muscular dystrophy.     

A research on the microfungal flora of somegreenhouse soils in the vicinity of LapsekiÇanakkale,Turkey

Qualitative and quantitative distributions of microfungal flora of the some greenhouse soils in the vicinity of Lapseki, Canakkale were studied. A total of 25 soil samples were collected from 10 cm depth in five greenhouses. Using soil dilution technique, 128 different microfungal isolates were obtained Isolates collected belonged to Oomycetes (1), Zygomycetes (7), Ascomycetes (9) and 96 belonging to the Deuteromycetes Fifteen isolates were classified as Mycelia Sterilia. The genera of microfungi most abundant in the greenhouse soils were Aspergillus, Penicillium, Geomyces, Exophiala and Fusarium. Qualitative and quantitative distributions of the Aspergillus were higher than those of the other genera. It was found that the maximum value was in greenhouse 5 and the minimum value was in greenhouse 4. The solarization method was the most effective in reducing fungal numbers.     

Duchenne muscular dystrophy – What causes the increased membrane permeability in skeletal muscle?

Duchenne muscular dystrophy is a severe muscle wasting disease caused by a mutation in the gene for dystrophin--a cytoskeletal protein connecting the contractile machinery to a group of proteins in the cell membrane. At the end stage of the disease there is profound muscle weakness and atrophy. However, the early stage of the disease is characterised by increased membrane permeability which allows soluble enzymes such as creatine kinase to leak out of the cell and ions such as calcium to enter the cell. The most widely accepted theory to explain the increased membrane permeability is that the absence of dystrophin makes the membrane more fragile so that the stress of contraction causes membrane tears which provide the increase in membrane permeability. However other possibilities are that increases in intracellular calcium caused by altered regulation of channels activate enzymes, such as phospholipase A(2), which cause increased membrane permeability. Increases in reactive oxygen species (ROS) are also present in the early stages of the disease and may contribute both to membrane damage by peroxidation and to the channel opening. Understanding the earliest phases of the pathology are critical to therapies directed at minimizing the muscle damage.     

Hominoid phalanges from the middle Miocene site of Paşalar, Turkey

Eleven proximal and ten intermediate partial or complete hominoid phalanges have been recovered from the middle Miocene site of Pa?alar in Turkey. Based on species representation at Pa?alar, it is likely that most or all of the phalanges belong to Griphopithecus alpani rather than Kenyapithecus kizili, but both species may be represented. All of the complete or nearly complete phalanges appear to be manual, so comparisons to extant and other fossil primate species were limited to manual phalanges. Comparisons were made to extant hominoid and cercopithecoid primate genera expressing a variety of positional repertoires and varying degrees of arboreality and terrestriality. The comparisons consisted of a series of bivariate indices derived from previous publications on Miocene catarrhine phalangeal morphology. The proximal phalanges have dorsally expanded proximal articular surfaces, which is characteristic of cercopithecoids and most other Miocene hominoids, and indicates that the predominant positional behaviors involved pronograde quadrupedalism. Among the extant primates, many of the proximal and intermediate phalangeal indices clearly distinguish more habitually terrestrial taxa from those that are predominantly arboreal, and especially from taxa that commonly engage in suspensory activities. For nearly every index, the values of the Pa?alar phalanges occupy an intermediate position-most similar to values for Pan and, to a lesser extent, Macaca-indicating a generalized morphology and probably the use of both arboreal and terrestrial substrates. At least some terrestrial activity is also compatible with reconstructions of the Pa?alar habitat. Most proximal and intermediate phalanges of other middle and late Miocene hominoids have similar index values to those of the Pa?alar specimens, revealing broadly similar manual phalangeal morphology among many Miocene hominoids.     

How does a g993t mutation in the emerin gene cause Emery-Dreifuss muscular dystrophy?

X-linked Emery-Dreifuss muscular dystrophy is usually caused by absence of the nuclear membrane protein, emerin, due to nonsense mutations or deletions, but a few missense mutations also exist. A pathogenic g993t mutation causes a Q133H change in the nuclear targeting region of emerin, but it may also reduce emerin levels by affecting mRNA splicing. We have introduced the g993t mutation by in vitro mutagenesis and studied the effect of Q133H on nuclear targeting by transfection of COS-7 cells. No qualitative or quantitative differences in nuclear targeting were observed between normal and mutant emerin. Quantitative BIAcore analysis showed no significant change in lamin A binding to emerin when the mutation was present. We conclude that Q133 is not essential for nuclear targeting of emerin or its interaction with lamin A. Reduced emerin levels due to altered splicing or defective interaction with an unidentified binding partner remain possible pathogenic mechanisms.     

DNA barcoding in native plants of the Labiatae (Lamiaceae) family from Chios Island (Greece) and the adjacent Çeşme-Karaburun Peninsula (Turkey)

The plant family Labiatae (Lamiaceae) is known for its fine medicinal and aromatic herbs like lavender, mint, oregano, sage and thyme and is a rich source of essential oils for the food, pharmaceutical and cosmetic industry. Besides its great economic importance, the Labiatae family contributes significantly to the endemic flora of Greece and Turkey. Owing to its economic and biological significance and to the difficult identification based on morphological characters of several of its taxa, the Labiatae family is an ideal case for developing DNA barcodes. The purpose of this study is to evaluate the utility of DNA barcoding on a local scale in discriminating Labiatae species in Chios Island (Greece) and the adjacent Çe?me‐Karaburun Peninsula (Turkey). We chose three cpDNA regions (matK, rbcL, trnH‐psbA) that were proposed by previous studies and tested them either as single region or as multiregion barcodes based on the criteria determined by Consortium for the Barcode of Life (CBOL). Our results show that matK and trnH‐psbA taken as useful in discriminating species of the Labiatae, for the species we examined, as any multiregion combination. matK and trnH‐psbA could serve as single‐region barcodes for Labiatae species contributing to the conservation and the trade control of valuable plant resources.     

Frequency and risk factors of dermatophytosis in students living in rural areas in Eskişehir,Turkey

Mycopathologia - Our study included 2384 students from five villages around Eski?ehir, Turkey. We asked every student for their personal identification and also for their sanitation in order...     

A new hominoid species from the middle Miocene site of Paşalar, Turkey

A new species of fossil hominoid is described from the middle Miocene deposits at Pa?alar, Turkey. It is the less common of the two Pa?alar species discussed by Martin and Andrews (1993), making up approximately 10% of the individuals in the Pa?alar hominoid sample according to analyses of the minimum number of individuals. To the diagnostic features of I(1) described by Alpagut et al. (1990) and Martin and Andrews (1993) can now be added further diagnostic features of all the anterior teeth, as well as both upper premolars and P(3). These include discrete, nonmetric features and metric differences at all the noted tooth positions. Attempts to distinguish the upper and lower molars of the two species have so far been unsuccessful, with the possible exception of M(3). The morphology of the new species is similar in most respects to that of Kenyapithecus wickeri from Fort Ternan, especially concerning maxillary morphology. They share robust and moderately deep maxillary alveolar processes, a restricted maxillary sinus with an elevated and uncomplicated floor, lacking the compartmentalization evident to varying degrees in many other taxa, and a zygomatic process that originates and turns laterally fairly high above the alveolar margin. There are also a number of distinctive similarities in the dentition, particularly for I(1), C(1), P(4) and P(3). The I(1) morphology in particular, with greatly hypertrophied lingual marginal ridges bounding a uniformly thickened basal crown area, is distinctive among Miocene hominoids. All of these similarities serve to reinforce the differences noted by others between the derived morphology of K. wickeri and the more primitive morphology of Equatorius africanus from Maboko and Kipsaramon. The new species differs from K. wickeri in morphological details of most of the anterior and premolar teeth that are known for both species, despite the general morphological similarity, and in the size of I(1) versus I(2). One striking feature of the new species is a relatively large incisive fossa, although it cannot be determined if this is associated with an open palatine fenestra, as in many early Miocene hominoids, or a minimally overlapping palate and nasoalveolar clivus, as in some middle and late Miocene hominoids.     

A small deletion in the Duchenne/Becker muscular dystrophy locus —a functionally important region?

Summary A DNA deletion in a patient with Becker muscular dystrophy (BMD) has been delineated by restriction endonuclease mapping. The deletion is unusually small, removing six kilobases (kb) of DNA distal to pERT 87-1 (DXS164). This region has previously been shown to contain an exon of a candidate gene which, when defective, causes Duchenne muscular dystrophy (DMD) or Becker muscular dystrophy. Removal of this exon and surrounding DNA is apparently sufficient, in this case, to cause a BMD phenotype. The occurrence of this deletion in DXS164 would appear to confirm that this region is part of the BMD locus. Many DMD patients have deletions in and around this region, adding further evidence for the allelic nature of the two disorders. This fortuitous deletion may identify a functionally important domain of the protein product in terms of the severity of phenotype manifested.     

Is there selection in favour of heterozygotes in families with merosin-deficient congenital muscular dystrophy?

Merosin-deficient congenital muscular dystrophy is an autosomal recessive neuromuscular disorder caused by partial or total absence of laminin-2 (merosin) in the skeletal muscle. Affected children have severe weakness, hypotonia at birth, high creatine kinase (CK) levels (more than 10 times normal) and are not able to walk or stand unsupported. Linkage and mutation analysis demonstrated that the gene encoding for the laminin-alpha2 chain, mapped on chromosome 6q22-23, is invariably responsible for this form of congenital muscular dystrophy. We investigated the pattern of inheritance of the haplotypes associated with the mutated allele in 29 informative merosin-deficient families, using tightly linked informative polymorphic microsatellite markers. This allowed us to identify heterozygous individuals from normal homozygotes, who are clinically, pathologically and biochemically indistinguishable. By linkage analysis, we found a statistically significant increase in the number of heterozygous individuals carrying either the paternal or the maternal haplotypes associated with the mutated allele. This could suggest a selection in favour of the alleles carrying mutations at the laminin alpha2-chain locus.     

Çeştepe,a new early Pliocene vertebrate locality in Central Anatolia and its stratigraphic context

The new locality of Çeştepe in the Kazan Basin, 45 km NNW of Ankara, yielded the remains of three species of reptiles (cf. Lacerta sp., Anguinae indet. and Varanus sp.) and an ochotonid lagomorph, Ochotona mediterranensis Suata Alpaslan, 2009. The latter species suggests an early Pliocene age (MN14). The fossil layer is included in the Sinap Formation that delivered abundant remains of Mio-Pliocene mammals in the southern part of the basin, but in the northern part of the basin Çeştepe is currently the unique fossil site. The age assigned by the fauna led to revise the stratigraphy of sedimentary formations in the Çeştepe area, previously confusing because of the various lithostratigraphic unit names and ages given in previous work. The taxa described in this note are still poorly known in Turkey. Varanus has been previously reported from Çalta, a locality 16.3 km SW to Çeştepe in the same basin, and O. mediterranensis from Iğdeli in the Sivas Basin. Although represented by a few taxa, the Çeştepe faunule shows Eurasian affinities.     

The deciduous dentition of Griphopithecus alpani from Paşalar, Turkey

Seventy-four hominoid primary teeth have been recovered from the middle Miocene site of Pa?alar, Turkey, constituting the largest sample of deciduous teeth for any species of fossil ape. Morphological features that characterize the permanent teeth of Griphopithecus alpani from the site have also been identified in some of these deciduous teeth, including a lingual pillar on the di(1)s. These features plus the overwhelming preponderance of G. alpani permanent teeth at the site suggest that all of the deciduous teeth belong to this species. Contrary to the situation in the permanent teeth, nothing in the morphology of the primary dentition suggests the representation of a second species. The age profile of the non-adult hominoids was reconstructed based on the degree and type of wear recorded on the dp4s, the most abundant deciduous tooth in the sample, assuming a similar eruption chronology to that of Pan troglodytes. This analysis indicates underrepresentation of very young individuals in the sample and high mortality for individuals belonging to the 3-5-years age cohort, a situation that could be due to the effects of stress related to weaning. The coefficient of variation and range-index values obtained for the majority of tooth types are equal to or greater than the comparable values in a sample of P. troglodytes, in some cases at much smaller sample sizes. One possible explanation for this is that there was greater sexual dimorphism in the G. alpani deciduous dentition than in Pan, which would mirror the condition of the permanent dentition.     

Age and origin of the FCMD 3′-untranslated-region retrotransposal insertion mutation causing Fukuyama-type congenital muscular dystrophy in the Japanese population

Fukuyama-type congenital muscular dystrophy (FCMD), an autosomal recessive disorder with a high prevalence in the Japanese population, is characterised by severe muscular dystrophy associated with brain malformation (cortical dysgenesis) and mental retardation. In Japan, 87% of FCMD-bearing chromosomes carry a 3-kb retrotransposal insertion of tandemly repeated sequences within the disease gene recently identified on chromosome 9q31, and most of them share a common founder haplotype. FCMD is the first human disease known to be caused primarily by an ancient retrotransposal integration. By applying two methods for the study of linkage disequilibrium between flanking polymorphic markers and the disease locus, and of its decay over time, the age of the insertion mutation causing FCMD in Japanese patients is calculated to be approximately 102 generations (95% confidence interval: 86-117 g), or slightly less. The estimated age dates the most recent common ancestor of the mutation-bearing chromosomes back to the time (or a few centuries before) the Yayoi people started migrating to Japan from the Korean peninsula. This finding makes the molecular population genetics of FCMD understandable in the context of Japan's history and the founder effect consistent with the prevalent theory on the origins of the modern Japanese population.