Characterization of species-specific repeated DNA sequences from B. nigra

Summary The construction and characterization of two genome-specific recombinant DNA clones from B. nigra are described. Southern analysis showed that the two clones belong to a dispersed repeat family. They differ from each other in their length, distribution and sequence, though the average GC content is nearly the same (45%). These B genome-specific repeats have been used to analyse the phylogenetic relationships between cultivated and wild species of the family Brassicaceae.     

Isolation, characterization and cross-species testing of microsatellites obtained from a sand smelt (Atherina boyeri) genomic library

This study reports the isolation and characterization of 11 polymorphic microsatellites from a sand smelt (Atherina boyeri) genomic library. Enrichment was performed with di-, tri- and tetranucleotide motifs following the FIASCO procedure (fast isolation by AFLP of sequences containing repeats). All loci were found to be in linkage and in Hardy-Weinberg equilibrium. This represents the first microsatellite isolation for the family Atherinidae and the isolated loci were accordingly tested on four additional species of the family: two recognized (A. presbyter and A. hepsetus) and two proposed ('punctata' and 'non-punctata' forms). Moreover their cross-species suitability on Menidia menidia, belonging to the same order but to the family Atherinopsidae, was also tested.     

Individual Odour Similarity and Discrimination in the Coruro (Spalacopus cyanus, Octodontidae)

Previous studies of subterranean, fossorial and above‐ground rodents have demonstrated that similarities in individual odours covary with genetic similarities thus supporting the theory of odour‐genes covariance (i.e. the closer the individuals are genetically, the greater the similarities between their odours). We used the habituation‐generalization paradigm, where the subject is exposed to the same odour stimulus in three consecutive habituation trials followed by two test trials in which the odour from two other individuals are presented successively. Using this test design, we showed that the socially living coruros (Spalacopus cyanus) discriminate individuals on the basis of their ano‐genital odours and also respond to odour similarities between individuals. Male and female subjects treated ano‐genital odours of two same‐sex family members and also the odours of two sibling strangers as different to each other. At the same time, they treated the odours of siblings as similar compared with the odour of an unrelated individual. No gender differences were detected. Our results contrast with those from other rodent species that did not spontaneously discriminate between individual odours of siblings from a different family than their own. The polygyneous lifestyle may provide the selective background for that difference. Additional research will be necessary to explore this hypothesis and to rule out differences due to dietary preferences and due to the type of paradigm chosen for the tests.     

Biliteracy and Schooling in an Extended-Family Nicaraguan Immigrant Household: The Sociohistorical Construction of Parental Involvement

Situating parental involvement in education within a sociohistorical context, this case study of a Nicaraguan immigrant household in California contrasts the perspectives of two sisters-inlaw who shared a home and whose daughters attended the same urban elementary school. Although the two women were involved in their daughters' schooling in different ways, the article illustrates how both women drew on a variety of personal, family, and community resources to support the girls' academic success.     

Function and structure studies of GH family 31 and 97 α-glycosidases

A huge number of glycoside hydrolases are classified into the glycoside hydrolase family (GH family) based on their amino-acid sequence similarity. The glycoside hydrolases acting on α-glucosidic linkage are in GH family 4, 13, 15, 31, 63, 97, and 122. This review deals mainly with findings on GH family 31 and 97 enzymes. Research on two GH family 31 enzymes is described: clarification of the substrate recognition of Escherichia coli α-xylosidase, and glycosynthase derived from Schizosaccharomyces pombe α-glucosidase. GH family 97 is an aberrant GH family, containing inverting and retaining glycoside hydrolases. The inverting enzyme in GH family 97 displays significant similarity to retaining α-glycosidases, including GH family 97 retaining α-glycosidase, but the inverting enzyme has no catalytic nucleophile residue. It appears that a catalytic nucleophile has been eliminated during the molecular evolution in the same way as a man-made nucleophile mutant enzyme, which catalyzes the inverting reaction, as in glycosynthase and chemical rescue.     

A Newly Isolated Family of Short Interspersed Repetitive Elements (Sines) in Coregonid Fishes (Whitefish) with Sequences That Are Almost Identical to Those of the Smai Family of Repeats: Possible Evidence for the Horizontal Transfer of Sines

The SmaI family of repeats is present only in the chum salmon and the pink salmon, and it is not present in five other species in the same genus or in other species in closely related genera. In the present study, we showed that another short interspersed repetitive elements (SINEs) family, which is almost identical to the SmaI family, is present in all fishes in the subfamily Coregoninae, being regarded as the most primitive salmonids. This new family of SINEs was designated the SmaI-cor family (SmaI family of repeats in coregonids). The consensus sequence of the SmaI-cor family was found to be 98.6% homologous to that of the SmaI family. Accordingly, it is difficult to explain the high degree of homology between these two families of SINEs by any mechanism other than the horizontal transfer of SINEs. The estimates of the rate of neutral mutation of nuclear genes, comparing chum salmon and European whitefish, confirmed this possibility. Our results strongly suggest that a member(s) of the SmaI-cor family might have been transferred horizontally from one coregonid species to a common ancestor of chum and pink salmon or to these two species independently, to allow subsequent amplification of the SmaI family in their respective genomes.     

New satellite DNA in Lacerta s. str. lizards (Sauria: Lacertidae): evolutionary pathways and phylogenetic impact

A new tandemly repeated (satellite) DNA family namely Agi160, from Lacerta agilis and Lacerta strigata (Lacerta sensu stricto (s. str.), Linnaeus 1758) have been cloned and sequenced. Agi160 is found in the above two species, as well as two other representatives of the same genus, L. viridis and L. media. DNA hybridization did not reveal it in Darevskia, Podarcis, Zootoca, Eremias, Ophisops, and Gallotia - the other genera of the family Lacertidae. The results suggest that Agi160 is a Lacerta s. str. specific family of tandem DNA repeats. However, a comparison between sequences of Agi160 and CLsat repeat units revealed 60 bp regions 62-74% identical. The latter is a satellite DNA family typical for Darevskia (syn. "L. saxicola complex") (Grechko et al., Molecular-genetic classification and phylogenetic relatedness of some species of Lacertidae lizards by taxonoprint data. Mol Biol 32:172-183, 1988.). Both Agi160 and CLsat tandem repeats share several common features (e.g., the same AT content and distribution of multiple short A-T runs, internal structure of repeated units, the presence of conservative regions). These data are indicative of their common origin and a possibly strong selective pressure upon conserving both satellites. A comparative analysis of structure, organization, and abundance of these two families of satDNA reveals evolutionary pathways that led to their formation and divergence. The data are consistent with the hypotheses of the concerted evolution of satellite DNA families. The possibility of use of Agi160 as a phylogenetic tool, defining relationships within Lacerta s. str., as well as within the whole family of Lacertidae is discussed.     

Specific DNA binding of the two chicken Deformed family homeodomain proteins, Chox-1.4 and Chox-a.

The cDNA clones encoding two chicken Deformed (Dfd) family homeobox containing genes Chox-1.4 and Chox-a were isolated. Comparison of their amino acid sequences with another chicken Dfd family homeodomain protein and with those of mouse homologues revealed that strong homologies are located in the amino terminal regions and around the homeodomains. Although homologies in other regions were relatively low, some short conserved sequences were also identified. E. coli-made full length proteins were purified and used for the production of specific antibodies and for DNA binding studies. The binding profiles of these proteins to the 5'-leader and 5'-upstream sequences of Chox-1.4 and Chox-a coding regions were analyzed by immunoprecipitation and DNase I footprint assays. These two Chox proteins bound to the same sites in the 5'-flanking sequences of their coding regions with various affinities and their binding affinities to each site were nearly the same. The consensus sequences of the high and low affinity binding sites were TAATGA(C/G) and CTAATTTT, respectively. A clustered binding site was identified in the 5'-upstream of the Chox-a gene, suggesting that this clustered binding site works as a cis-regulatory element for auto- and/or cross-regulation of Chox-a gene expression.     

Differences in intrapartum obstetric care provided to women at low risk by family physicians and obstetricians.

To determine differences in practice style and to examine maternal and neonatal outcomes, we reviewed the hospital charts of 1115 women admitted by family physicians and 1250 women admitted by obstetricians who gave birth at one of three teaching hospitals in Toronto between April 1985 and March 1986. All the women in the two groups were categorized retrospectively as being at low risk at the onset of labour on the basis of their prenatal records and their admission histories and physical examination results. There were higher proportions of younger women and women of lower socioeconomic status in the family physician group than in the obstetrician group (p less than 0.001). The rates of interventions, including artificial rupture of the membranes, induction, augmentation, low forceps plus vacuum extraction, episiotomy and epidural anesthesia, were all higher in the obstetrician group. The mean birth weight and the cesarean section rate were the same in the two groups. Differences in labour and delivery outcomes between the two groups, including a higher rate of spontaneous vaginal delivery for the family physicians, reflected a more "expectant" practice style by family doctors. However, there were no significant differences in the rates of maternal or neonatal complications. A practice style characterized by a higher rate of interventions was not associated with improved maternal or newborn outcome in this low-risk setting.     

Wild-type Flp recombinase cleaves DNA in trans.

Site-specific recombinases of the Integrase family utilize a common chemical mechanism to break DNA strands during recombination. A conserved Arg-His-Arg triad activates the scissile phosphodiester bond, and an active-site tyrosine provides the nucleophile to effect DNA cleavage. Is the tyrosine residue for the cleavage event derived from the same recombinase monomer which provides the RHR triad (DNA cleavage in cis), or are the triad and tyrosine derived from two separate monomers (cleavage in trans)? Do all members of the family follow the same cleavage rule, cis or trans? Solution studies and available structural data have provided conflicting answers. Experimental results with the Flp recombinase which strongly support trans cleavage have been derived either by pairing two catalytic mutants of Flp or by pairing wild-type Flp and a catalytic mutant. The inclusion of the mutant has raised new concerns, especially because of the apparent contradictions in their cleavage modes posed by other Int family members. Here we test the cleavage mode of Flp using an experimental design which excludes the use of the mutant protein, and show that the outcome is still only trans DNA cleavage.     

Craniofacial pattern profile (CFPP) evaluation of facial dysmorphology in a familial syndrome with corneal anesthesia and multiple congenital anomalies

Roentgencephalometric findings are presented for a family with an unusual facial morphology. Twenty measurements defining the size and shape of major anatomic areas of the head and face were taken. The measurements were transformed into Z-scores. Using the sigma z (i.e., standard deviation of the Z-scores) value, an estimate of craniofacial pattern deviation from the norms was made for each family member. All members of this family have highly aberrant, i.e., dysmorphic, craniofacial pattern profiles. Familial as well as syndromic craniofacial similarities vs. dissimilarities between Z-score values of pairs of family members were assessed by the Pearson's correlation coefficient rz. Results of correlation coefficients demonstrate a high level (far in excess of the expected value of rz 0.50) of craniofacial pattern profile (CFPP) similarity between sibs and between sibs and their mother. This strongly suggests that the two sibs and their mothers are the carrier of the same genetic syndrome.     

Function and Structure Studies of GH Family 31 and 97 α-Glycosidases

A huge number of glycoside hydrolases are classified into the glycoside hydrolase family (GH family) based on their amino-acid sequence similarity. The glycoside hydrolases acting on α-glucosidic linkage are in GH family 4, 13, 15, 31, 63, 97, and 122. This review deals mainly with findings on GH family 31 and 97 enzymes. Research on two GH family 31 enzymes is described: clarification of the substrate recognition of Escherichia coli α-xylosidase, and glycosynthase derived from Schizosaccharomyces pombe α-glucosidase. GH family 97 is an aberrant GH family, containing inverting and retaining glycoside hydrolases. The inverting enzyme in GH family 97 displays significant similarity to retaining α-glycosidases, including GH family 97 retaining α-glycosidase, but the inverting enzyme has no catalytic nucleophile residue. It appears that a catalytic nucleophile has been eliminated during the molecular evolution in the same way as a man-made nucleophile mutant enzyme, which catalyzes the inverting reaction, as in glycosynthase and chemical rescue.     

家族传播的口腔白色念珠菌基因型多态性分析

目的检测家族传播的口腔白色念珠菌基因多态性。方法采集35个家庭（119个样本）的口腔牙菌斑,采用PCR ITS1-ITS2基因分型方法,检测、分析家族传播的口腔白色念珠菌基因多态性。结果 18个家庭（18/35,61%）,34个样本（34/119,28.6%）有白色念珠菌感染,11个家庭存在家族传播（11/18,61%）。在5个母子（父子）垂直传播的家庭成员中,白色念珠菌基因型均不一致。在3个呈水平传播的家庭成员中,两家基因型一致,1家不一致。在3个垂直-水平传播的家庭成员中,两家基因型一致,1家不一致。白色念珠菌家族传播基因型差异有显著统计学意义（χ2=26.571,P〈0.01）。白色念珠菌感染与年龄、性别、学历、吸烟、饮酒、义齿和龋病均无显著相关。结论白色念珠菌在口腔定植,受宿主自身遗传背景影响较大,在家族垂直传播中呈明显的基因多态性。呈水平传播的白色念珠菌菌种具有较高的传染性,基因型可保持不变。     

Correspondence between performance of Eucalyptus spp trees selected from family and clonal tests

We examined the correspondence in performance between trees selected from a family test and their respective clones from a clonal test of Eucalyptus. Full-sib families were obtained from controlled pollination among individuals of Eucalyptus grandis and between E. grandis and E. urophylla. The hybridizations did not follow a factorial scheme. The family tests were carried out at three locations in Eunápolis and Itabela counties, in Bahia, Brazil, in 2003. Four hundred and ninety-seven high-performance trees were selected, by the individual BLUP procedure, in the family tests at two years of age, based on wood volume. The clones from these trees and 14 checks were evaluated in clonal tests carried out in the same region in 2006. The wood volume of the clones was evaluated at two years of age. Trait correlation between the trees selected from the family and clonal tests was low. The estimate of the coincidence between the best trees and the best clones using an average of the different intensities of selection was only 27%. These results demonstrate that the selection of trees in the family test should not be too drastic; otherwise the chance plus clones may be overlooked.     

Phenotype–genotype analysis in two Chinese families with Liddle syndrome

The families with Liddle syndrome show marked phenotypic variation in blood pressure, serum potassium and other clinical manifestations. Here we analyzed the correlation of genotype–phenotype in two Chinese families with Liddle syndrome. The sequence of C-terminus of SCNN1B and SCNN1G were screened in the two families with likely Liddle syndrome. In addition to hypertension and hypokalemia, one of the two pedigrees had sudden death in their family members, so the exons of 428 reported genes-related to cardiovascular diseases were screened as well in the family. A heterozygous βR566X nonsense mutation was found in the proband-1 in the first pedigree, and the proband’s sister and father. They showed mild phenotype with hypertension under control. In contrast, two of the four previous studies report that the mutation causes severe phenotype. A heterozygous βR597PfrX607 frameshift mutation was identified in the proband-2 in the second pedigree, showing malignant phenotype including resistant hypertension, hypokalemia, higher PRA and plasma angiotensin II levels. Both the proband-2 and the proband-2’s father had sudden death in their twenties, but no meaningful mutations were found by screening of the exons in 428 cardiovascular disease-related genes. However, the same mutation has been related to moderate phenotype in previous studies. Our results confirmed that the phenotypes of Liddle syndrome are varied significantly even with the same mutation. The mechanisms why the same mutation causes very different phenotype need to be explored because intervention of these modifiers may change the disease course and prognosis accordingly.     

Parallel evolution of ligand specificity between LacI/GalR family repressors and periplasmic sugar-binding proteins

The bacterial LacI/GalR family repressors such as lactose operon repressor (LacI), purine nucleotide synthesis repressor (PurR), and trehalose operon repressor (TreR) consist of not only the N-terminal helix-turn-helix DNA-binding domain but also the C-terminal ligand-binding domain that is structurally homologous to periplasmic sugar-binding proteins. These structural features imply that the repressor family evolved by acquiring the DNA-binding domain in the N-terminal of an ancestral periplasmic binding protein (PBP). Phylogenetic analysis of the LacI/GalR family repressors and their PBP homologues revealed that the acquisition of the DNA-binding domain occurred first in the family, and ligand specificity then evolved. The phylogenetic tree also indicates that the acquisition occurred only once before the divergence of the major lineages of eubacteria, and that the LacI/GalR and the PBP families have since undergone extensive gene duplication/loss independently along the evolutionary lineages. Multiple alignments of the repressors and PBPs furthermore revealed that repressors and PBPs with the same ligand specificity have the same or similar residues in their binding sites. This result, together with the phylogenetic relationship, demonstrates that the repressors and the PBPs individually acquired the same ligand specificity by homoplasious replacement, even though their genes are encoded in the same operon.     

Biochemical,genetic, psychometric,and neuropsychological studies in heterozygotes of a family with globoid cell leucodystrophy (Krabbe's disease)

Summary Detection of a patient suffering from Krabbe's disease led to carrier screening in his family. Determination of galactosylceramide -galactosidase activity revealed the occurrence of two different alleles among the carriers of the same family. Heterozygotes and their noncarrier relatives were studied using psychometric and neuropsychological tests under blind conditions. It was found that compared to seven adult noncarrier relatives 19 adult carriers differ significantly in their general IQ and some subtests of the Wechsler Intelligence Scale for adults (WISA), including spatial cognition. Reaction times were significantly slower in the carriers with enzyme activity below 25% of the control values. Most of the carriers of this family have had myopia since early childhood.Dedicated to Professor Detlev Ploog on the occasion of his 60th birthday     

A maternal inherited translocation t(1;22)(q11;p11) in two infertile brothers

We report two infertile brothers presenting with azoospermia and oligozoospermia. Cytogenetic studies using G-banding and FISH analysis on lymphocyte cultures revealed an autosomal balanced reciprocal translocation t(1;22)(q11;p11) in both males. The same translocation was found in their mother, but not in a third fertile brother and maternal uncle suggesting that this translocation might compromise the male but not the female gametogenesis in this family.     

C-band variability and phylogeny of Lacertidae

The karyology of various species from the family Lacertidae (Reptilia, Sauria) has been studied with conventional and C-banding techniques.The study shows that this family is not so conservative from a karyological viewpoint as considered till now. In fact a higher diploid number than that generally observed in most species of Lacertidae and supernumerary chromosomes have been observed in three of the species investigated. Moreover an evident interand intraspecific variability has been found in the C-banding pattern of the various species studied. The situation found in Podarcis sicula is particularly remarkable. Different C-banding patterns have been observed in three different subspecies and in two populations of the same subspecies. These variations do not show a well defined trend and their role in the evolution of lacertid lizards is discussed.The C-banding analysis evidences also the existence in two of the species studied of a female sex heteromorphism, in which the W chromosome has the same shape and size as the Z, but differs from it in being completely heterochromatic. This situation reminds that observed in some snakes and suggests that in lacertid lizards the evolution of sex chromosomes might have followed the same steps previously hypothesized for ophidians.