Genes,symptoms, and the “asymptomatic ill”: toward a broader understanding of genetic discrimination

Since the early 1990s, the term “genetic discrimination” has been used to designate adverse treatment on the grounds of genetic makeup. However, the full spectrum of possible disadvantage associated with genetic information has not been addressed by either the international scientific debate or statutory arrangements on genetic discrimination. Informed by legal contexts, they almost all focus on one specific group: the “asymptomatic ill.” On the basis of the sociological study, “Genetic Discrimination in Germany,” this article proposes to revise the terms of the debate and discusses some limitations of the concept. Drawing on the experiences reported by affected individuals, it advocates a more expansive social understanding which does not require that a person has to be healthy to be at risk of genetic discrimination.     

The Relative Significance of Host–Habitat,Depth, and Geography on the Ecology,Endemism, and Speciation of Coral Endosymbionts in the Genus Symbiodinium

Dinoflagellates in the genus Symbiodinium are among the most abundant and important group of eukaryotic microbes found in coral reef ecosystems. Recent analyses conducted on various host cnidarians indicated that Symbiodinium assemblages in the Caribbean Sea are genetically and ecologically diverse. In order to further characterize this diversity and identify processes important to its origins, samples from six orders of Cnidaria comprising 45 genera were collected from reef habitats around Barbados (eastern Caribbean) and from the Mesoamerican barrier reef off the coast of Belize (western Caribbean). Fingerprinting of the ribosomal internal transcribed spacer 2 identified 62 genetically different Symbiodinium. Additional analyses of clade B Symbiodinium using microsatellite flanker sequences unequivocally characterized divergent lineages, or “species,” within what was previously thought to be a single entity (B1 or B184). In contrast to the Indo-Pacific where host-generalist symbionts dominate many coral communities, partner specificity in the Caribbean is relatively high and is influenced little by the host’s apparent mode of symbiont acquisition. Habitat depth (ambient light) and geographic isolation appeared to influence the bathymetric zonation and regional distribution for most of the Symbiodinium spp. characterized. Approximately 80% of Symbiodinium types were endemic to either the eastern or western Caribbean and 40–50% were distributed to compatible hosts living in shallow, high-irradiance, or deep, low-irradiance environments. These ecologic, geographic, and phylogenetic patterns indicate that most of the present Symbiodinium diversity probably originated from adaptive radiations driven by ecological specialization in separate Caribbean regions during the Pliocene and Pleistocene periods.     

Cloning,Sequencing, and Expression of the Genes Encoding an Isocyclomaltooligosaccharide Glucanotransferase and an α-Amylase from a Bacillus circulans Strain

The gene for a novel glucanotransferase, isocyclomaltooligosaccharide glucanotransferase (IgtY), involved in the synthesis of a cyclomaltopentaose cyclized by an α-1,6-linkage [ICG5; cyclo-{→6)-α-D-Glcp-(1→4)-α-D-Glcp-(1→4)-α-D-Glcp-(1→4)-α-D-Glcp-(1→4)-α-D-Glcp-(1→}] from starch, was cloned from the genome of B. circulans AM7. The IgtY gene, designated igtY, consisted of 2,985 bp encoding a signal peptide of 35 amino acids and a mature protein of 960 amino acids with a calculated molecular mass of 102,071 Da. The deduced amino-acid sequence showed similarities to 6-α-maltosyltransferase, α-amylase, and cyclomaltodextrin glucanotransferase. The four conserved regions common in the α-amylase family enzymes were also found in this enzyme, indicating that this enzyme should be assigned to this family. The DNA sequence of 8,325-bp analyzed in this study contained two open reading frames (ORFs) downstream of igtY. The first ORF, designated igtZ, formed a gene cluster, igtYZ. The amino-acid sequence deduced from igtZ exhibited no similarity to any proteins with known or unknown functions. IgtZ was expressed in Escherichia coli, and the enzyme was purified. The enzyme acted on maltooligosaccharides that have a degree of polymerization (DP) of 4 or more, amylose, and soluble starch to produce glucose and maltooligosaccharides up to DP5 by a hydrolysis reaction. The enzyme (IgtZ), which has a novel amino-acid sequence, should be assigned to α-amylase. It is notable that both IgtY and IgtZ have a tandem sequence similar to a carbohydrate-binding module belonging to a family 25. These two enzymes jointly acted on raw starch, and efficiently generated ICG5.     

Economics,human biology and inequality: A review of “puzzles” and recent contributions from a Deatonian perspective

The Nobel laureate Angus Deaton concentrated his work on puzzling developments and phenomena in economics. Puzzles are exciting elements in economics, because readers feel challenged by the question of how they can be solved. Among the puzzles analyzed by Deaton are: (1) Mortality increase of white, U.S. non-Hispanic men (2000 to today); (2) Why are height and income sometimes closely correlated, but not always?; (3) Height inequality among males and females; and (4) The Indian puzzle of declining consumption of calories during overall expenditure growth.This article reviews these “puzzles” and the main insights that Deaton derived from their discussion insofar as they pertain to the biological aspects of human development. I will focus on the field of this journal, Economics and Human Biology, in which Deaton has been very active over the last two decades. I will also document some of the responses by other scholars and their contributions to these puzzles, as they relate to the field of economics and human biology.     

Structural and Biochemical Analyses of Glycoside Hydrolase Family 26 β-Mannanase from a Symbiotic Protist of the Termite Reticulitermes speratus

Termites and their symbiotic protists have established a prominent dual lignocellulolytic system, which can be applied to the biorefinery process. One of the major components of lignocellulose from conifers is glucomannan, which comprises a heterogeneous combination of β-1,4-linked mannose and glucose. Mannanases are known to hydrolyze the internal linkage of the glucomannan backbone, but the specific mechanism by which they recognize and accommodate heteropolysaccharides is currently unclear. Here, we report biochemical and structural analyses of glycoside hydrolase family 26 mannanase C (RsMan26C) from a symbiotic protist of the termite Reticulitermes speratus. RsMan26C was characterized based on its catalytic efficiency toward glucomannan, compared with pure mannan. The crystal structure of RsMan26C complexed with gluco-manno-oligosaccharide(s) explained its specificities for glucose and mannose at subsites −5 and −2, respectively, in addition to accommodation of both glucose and mannose at subsites −3 and −4. RsMan26C has a long open cleft with a hydrophobic platform of Trp⁹⁴ at subsite −5, facilitating enzyme binding to polysaccharides. Notably, a unique oxidized Met⁸⁵ specifically interacts with the equatorial O-2 of glucose at subsite −3. Our results collectively indicate that specific recognition and accommodation of glucose at the distal negative subsites confers efficient degradation of the heteropolysaccharide by mannanase.     

Dinoflagellate cysts,Acritarchs and Tasmanitids from the uppermost Callovian of England and Scotland: With a reconsideration of the “xanthidium pilosum” problem

Four assemblages of fossil organic-walled microphytoplankton from the Upper Callovian (Lamberti Zone), three from England and one from Scotland, are described. They comprise at least 50 species of dinoflagellate cysts, 18 species of acritarchs and 2 species of tasmanitids. After a review of the «Xanthidium pilosum problem, a revised diagnosis is proposed for Sentusidinium pilosum (Ehrenberg) and three new species, Sentusidinium creberbarbatum, S. sparsibarbatum and S. erythrocomum are proposed. The new family name Scriniodiniaceae is substituted for the now invalid family name Endoscriniaceae. The new genus Escharisphaeridia is proposed to contain two existing species, E. pococki (Sarjeant) and E. dictydia (Sarjeant). The present content of the genus Compositosphaeridium is examined; the new combination C. polonicum (Górka) is proposed and a new species, C. bulgaricum, is erected. One further new species of dinoflagellate cyst, Prolixosphaeridium anasillum, is proposed. The new term «peniplate is proposed for paraplates whose boundaries are penitabular in situation.One new species of acritarch, Solisphaeridium?rhachos, is described and the new combination Polygonium aster (Sarjeant) is proposed. Evidence for reworking of some of the species of Micrhystridium present in the Hackness Rock assemblage is noted, though it is considered that the majority of species in that assemblage are indigenous. It is considered that all four assemblages are derived from a single phytoplankton province, the differences between them resulting from environmental factors such as water depth or distance from a shoreline.     

Detection of ‘Candidatus Cardinium’ Bacteria from the Haploid Host Brevipalpus Californicus (Acari: Tenuipalpidae) and Effect on the Host

Brevipalpus californicus (Banks) was infected with ‘Candidatus Cardinium’ bacteria (Cardinium). Tetracycline-treated females produced many male progeny even though untreated females produced only female progeny. B. californicus appears to be feminized by Cardinium. The values for net reproduction rate (R₀), generation time (T) and intrinsic rate of natural increase (r_m) calculated for B. californicus were 7.48/day, 31.45 days and 0.064/day, respectively. The comparison of infected females with uninfected males and other closely related species, indicated that Cardinium does not have a negative effect on the fitness of B. californicus.     

Deletion of the Schizophyllum Commune Aα Locus: The Roles of Aα Y and Z Mating-Type Genes

The Aα locus is one of four master regulatory loci that determine mating type and regulate sexual development in Schizophyllum commune. We have made a plasmid containing a URA1 gene disruption of the Aα Y1 gene. Y1 is the sole Aα gene in Aα1 strains. We used the plasmid construction to produce an Aα null (i.e., AαΔ) strain by replacing the genomic Y1 gene with URA1 in an Aα1 strain. To characterize the role of the Aα genes in the regulation of sexual development, we transformed various Aα Y and Z alleles into AαΔ strains and examined the acquired mating types and mating abilities of the transformants. These experiments demonstrate that the Aα Y gene is not essential for fungal viability and growth, that a solitary Z Aα mating-type gene does not itself activate development, that Aβ proteins are sufficient to activate the A developmental pathway in the absence of Aα proteins and confirm that Y and Z genes are the sole determinants of Aα mating type. The data from these experiments support and refine our model of the regulation of A-pathway events by Y and Z proteins.     

A Phenotypic,Molecular and Biochemical Characterization of the First Cisgenic Scab-Resistant Apple Variety ‘Gala’

Scab resistance is one of the most important goals of apple breeding, typically achieved by time-consuming and expensive conventional breeding techniques. Cisgenesis, which is the genetic modification of a recipient organism with genes from a crossable—sexually compatible—organism, is a promising tool for plant breeding to develop disease resistance in a rapid way. A cisgenic, scab-resistant line of the apple variety ‘Gala’ expressing the native apple scab resistance gene Rvi6 (formerly HcrVf2) under control of its own regulatory sequences has been recently developed. In this paper, we present the results from a phenotypic, molecular and biochemical evaluation of clonal replicates of this line (C11.1.53). The phenotype (shoot length, shoot diameter, internode length, number of leaves, leaf length and leaf width) of C11.1.53 was compared to that of the Gala parental background over a period of 108 days. Only a few statistically significant differences were detected, which are probably due to small differences in the quality of the budwood used for grafting rather than effects related to the presence of the cisgene. As the expression of a resistance gene can affect the downstream cascade of plant defence responses, a selection of apple defence-related genes was analyzed by quantitative real-time PCR analysis. These genes are also known as major allergen genes in apple. Even if three out of ten apple allergen genes tested in the leaves differed in the cisgenic line compared to both Gala (background) and ‘Florina’ (the variety from which the Rvi6 gene was cloned), using 2D-PAGE, we were unable to find any significant difference in the expressed proteomes of the leaves of C11.1.53 compared to Gala. Results are discussed in the context of a possible use of cisgenic lines for fruit crop improvement.     

A new linear-leaved Cyanea (Campanulaceae: Lobelioideae) from Kaua'i,and the “rediscovery” of Cyanea linearifolia

Cyanea kuhihewa (Campanulaceae: Lobelioideae) is described from Kaua'i in the Hawaiian Islands and assigned to sect.Hirtellae. Because of its leaves, it was first identified asC. linearifolia, a member of sect.Delisseoideae presumed extinct. However, the new species differs by its flat or slightly revolute (vs. strongly revolute) leaf margins, fewer-flowered pubescent inflorescences with shorter peduncles and bracts longer than wide (vs. wider than long), and larger pubescent flowers.     

Wide Distribution and Genetic Diversity of “Candidatus Neoehrlichia mikurensis” in Rodents from China

“Candidatus Neoehrlichia mikurensis” was detected by PCR in 4.0% (34/841) of the rodents tested in this study. The 34 rodents represented nine species from seven regions of China. Phylogenetic analyses based on the partial groEL and nearly entire 16S rRNA gene sequences of the agent revealed genetic diversity, which was correlated with its geographic origins.     

A South American snake lineage from the Eocene Greenhouse of North America and a reappraisal of the fossil record of “anilioid” snakes

“Anilioidea” is a likely paraphyletic assemblage of pipe snakes that includes extant Aniliidae from equatorial South America, Uropeltoidea from South and Southeast Asia, and a fossil record that consists primarily of isolated precloacal vertebrae ranging from the earliest Late Cretaceous and includes geographic distributions in North America, South America, Europe, and Africa. Articulated precloacal vertebrae from the middle Eocene Bridger Formation of Wyoming, attributed to Borealilysia nov. gen., represent an unambiguous North American aniliid record and prompts a reconsideration of described pipe snakes and their resultant biogeographic histories. On the basis of vertebral apomorphies, the vast majority of reported fossils cannot be assigned to “Anilioidea”. Instead, most records represent stem taxa and macrostomatans erroneously assigned to anilioids on the basis of generalized features associated with fossoriality. A revised fossil record demonstrates that the only extralimital distributions of fossil “anilioids” consist of the North American aniliid record, and there is no unambiguous fossil record of Old World taxa. The occurrence of aniliids in the mid-high latitudes of the late early Eocene of North America is consistent with histories of northward shifts in equatorial ecosystems during the early Paleogene Greenhouse.     

Binding from Both Sides: TolR and Full-Length OmpA Bind and Maintain the Local Structure of the E. coli Cell Wall

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