Turtle hatchlings show behavioral types that are robust to developmental manipulations.

There can be substantial variation among individuals within a species in how they behave, even under similar conditions; this pattern is found in many species and across taxa. However, the mechanisms that give rise to this behavioral variation are often unclear. This study investigated the influence of environmental manipulations during development on behavioral variation in hatchlings of the red-eared slider turtle (Trachemys scripta). First, we examined the effects of three manipulations during incubation (estrone sulfate exposure, corticosterone exposure, and thermal fluctuations) on hatchling righting response and exploration. Second, we determined whether hatchlings showed consistent differences (i.e. behavioral types) in their righting response and exploration across days and months, and whether these behaviors were correlated with one another. Finally, we examined whether righting response was predictive of ecologically relevant behaviors such as habitat choice and dispersal. Hatchling behavior was robust to our early manipulations; none of the pre-hatch treatments affected later behavior. There were significant clutch effects, which due to the split-clutch design suggests genetic underpinnings and/or maternal effects. We found evidence for behavioral types in turtles; both righting response and exploration were strongly repeatable and these behaviors were positively correlated. Righting response was not predictive of dispersal ability in the field, necessitating a revision in the general interpretations of righting response as a proxy for dispersal ability in turtles. Thus, turtle hatchlings show consistent behavioral differences that are robust to early developmental manipulations, and while not necessarily predictive of dispersal, these behavioral types can have important consequences throughout ontogeny.

Genome-wide association study of major depressive disorder: new results, meta-analysis, and lessons learned.

Major depressive disorder (MDD) is a common complex disorder with a partly genetic etiology. We conducted a genome-wide association study of the MDD2000+ sample (2431 cases, 3673 screened controls and >1 M imputed single-nucleotide polymorphisms (SNPs)). No SNPs achieved genome-wide significance either in the MDD2000+ study, or in meta-analysis with two other studies totaling 5763 cases and 6901 controls. These results imply that common variants of intermediate or large effect do not have main effects in the genetic architecture of MDD. Suggestive but notable results were (a) gene-based tests suggesting roles for adenylate cyclase 3 (ADCY3, 2p23.3) and galanin (GAL, 11q13.3); published functional evidence relates both of these to MDD and serotonergic signaling; (b) support for the bipolar disorder risk variant SNP rs1006737 in CACNA1C (P=0.020, odds ratio=1.10); and (c) lack of support for rs2251219, a SNP identified in a meta-analysis of affective disorder studies (P=0.51). We estimate that sample sizes 1.8- to 2.4-fold greater are needed for association studies of MDD compared with those for schizophrenia to detect variants that explain the same proportion of total variance in liability. Larger study cohorts characterized for genetic and environmental risk factors accumulated prospectively are likely to be needed to dissect more fully the etiology of MDD.

Genome-wide association studies establish that human intelligence is highly heritable and polygenic.

General intelligence is an important human quantitative trait that accounts for much of the variation in diverse cognitive abilities. Individual differences in intelligence are strongly associated with many important life outcomes, including educational and occupational attainments, income, health and lifespan. Data from twin and family studies are consistent with a high heritability of intelligence, but this inference has been controversial. We conducted a genome-wide analysis of 3511 unrelated adults with data on 549,692 single nucleotide polymorphisms (SNPs) and detailed phenotypes on cognitive traits. We estimate that 40% of the variation in crystallized-type intelligence and 51% of the variation in fluid-type intelligence between individuals is accounted for by linkage disequilibrium between genotyped common SNP markers and unknown causal variants. These estimates provide lower bounds for the narrow-sense heritability of the traits. We partitioned genetic variation on individual chromosomes and found that, on average, longer chromosomes explain more variation. Finally, using just SNP data we predicted ∼1% of the variance of crystallized and fluid cognitive phenotypes in an independent sample (P=0.009 and 0.028, respectively). Our results unequivocally confirm that a substantial proportion of individual differences in human intelligence is due to genetic variation, and are consistent with many genes of small effects underlying the additive genetic influences on intelligence.

Genome-wide association for major depressive disorder: a possible role for the presynaptic protein piccolo.

Major depressive disorder (MDD) is a common complex trait with enormous public health significance. As part of the Genetic Association Information Network initiative of the US Foundation for the National Institutes of Health, we conducted a genome-wide association study of 435 291 single nucleotide polymorphisms (SNPs) genotyped in 1738 MDD cases and 1802 controls selected to be at low liability for MDD. Of the top 200, 11 signals localized to a 167 kb region overlapping the gene piccolo (PCLO, whose protein product localizes to the cytomatrix of the presynaptic active zone and is important in monoaminergic neurotransmission in the brain) with P-values of 7.7 x 10(-7) for rs2715148 and 1.2 x 10(-6) for rs2522833. We undertook replication of SNPs in this region in five independent samples (6079 MDD independent cases and 5893 controls) but no SNP exceeded the replication significance threshold when all replication samples were analyzed together. However, there was heterogeneity in the replication samples, and secondary analysis of the original sample with the sample of greatest similarity yielded P=6.4 x 10(-8) for the nonsynonymous SNP rs2522833 that gives rise to a serine to alanine substitution near a C2 calcium-binding domain of the PCLO protein. With the integrated replication effort, we present a specific hypothesis for further studies.

A common variant in the 3'UTR of the GRIK4 glutamate receptor gene affects transcript abundance and protects against bipolar disorder.

Underactivity of the glutamatergic system is an attractive model for the pathophysiology of several major mental illnesses. We previously described a chromosome abnormality disrupting the kainate class ionotropic glutamate receptor gene, GRIK4/KA1, in an individual with schizophrenia and learning disability (mental retardation). We also demonstrated in a case-control study that two physically separated haplotypes within this gene were significantly associated with increased risk of schizophrenia and decreased risk of bipolar disorder, respectively. The latter protective haplotype was located at the 3' end of the gene. We now report the identification from carriers of the protective haplotype of a deletion variant within the 3' untranslated region of the gene. The deletion allele also was found to be negatively associated with bipolar disorder in both initial (P = 0.00000019) and replication (P = 0.0107) case-control studies. Expression studies indicated that deletion-carrying mRNA transcripts were relatively more abundant. We postulate that this may be a direct consequence of the differences in the RNA secondary structures predicted for the insertion and deletion alleles. These data suggest a mechanism whereby the genetic protective effect is mediated through increased kainate receptor expression.

Whole-genome association study of bipolar disorder.

We performed a genome-wide association scan in 1461 patients with bipolar (BP) 1 disorder, 2008 controls drawn from the Systematic Treatment Enhancement Program for Bipolar Disorder and the University College London sample collections with successful genotyping for 372,193 single nucleotide polymorphisms (SNPs). Our strongest single SNP results are found in myosin5B (MYO5B; P=1.66 x 10(-7)) and tetraspanin-8 (TSPAN8; P=6.11 x 10(-7)). Haplotype analysis further supported single SNP results highlighting MYO5B, TSPAN8 and the epidermal growth factor receptor (MYO5B; P=2.04 x 10(-8), TSPAN8; P=7.57 x 10(-7) and EGFR; P=8.36 x 10(-8)). For replication, we genotyped 304 SNPs in family-based NIMH samples (n=409 trios) and University of Edinburgh case-control samples (n=365 cases, 351 controls) that did not provide independent replication after correction for multiple testing. A comparison of our strongest associations with the genome-wide scan of 1868 patients with BP disorder and 2938 controls who completed the scan as part of the Wellcome Trust Case-Control Consortium indicates concordant signals for SNPs within the voltage-dependent calcium channel, L-type, alpha 1C subunit (CACNA1C) gene. Given the heritability of BP disorder, the lack of agreement between studies emphasizes that susceptibility alleles are likely to be modest in effect size and require even larger samples for detection.

Speciation in killifish and the role of salt tolerance.

Species pairs whose distributions are tied to environmental conditions provide intriguing candidates for the study of ecological speciation. Here, we examine the role that adaptation to salinity has played in the divergence between two closely related species, Lucania goodei and Lucania parva, whose distributions reflect salinity (L. goodei- fresh water, L. parva- euryhaline). We first tested whether these two species display local adaptation and, subsequently, tested for ecological, genic and behavioural isolation by performing crosses within and between L. goodei and L. parva and raising offspring under various salinities. We found strong evidence for differential adaptation to salinity and also for behavioural isolation where animals preferentially mated with conspecifics over heterospecifics. However, we found no evidence for F1 hybrid inviability. We discuss the general lack of evidence for genic isolation in teleost fish and whether this is a real phenomenon or simply a reflection of experimental design.

Evidence for association and epistasis at the DAOA/G30 and D-amino acid oxidase loci in an Irish schizophrenia sample.

The D-amino acid oxidase (DAO) signaling pathway has been implicated in schizophrenia pathogenesis. This may be mediated through modulation of NMDA function by DAO, which is in turn activated by DAO activator (DAOA, formerly G72). Chumakov et al. (2002); PNAS 99: 13675-13680, identifying the novel schizophrenia susceptibility gene DAOA/G30 and a number of independent studies have since reported evidence of association between the DAOA and DAO genes and schizophrenia. However, at least two studies have failed to replicate the epistatic interaction between these loci described in the original report and there have been differences in the associated alleles/haplotypes reported at each locus. In this study, we performed association and epistasis analyses of the DAOA/G30 and DAO loci in a sample of 373 cases with DSM-IV schizophrenia/schizoaffective disorder and 812 controls from the Republic of Ireland. Corrected for the number of tests performed, we found evidence for association between markers at both genes and schizophrenia: DAOA/G30 (P = 0.005, OR = 1.34 (1.09, 1.65)) and DAO (P = 0.003, OR = 1.43 (1.12, 1.84). The data suggest that evidence for association at DAO (marker rs2111902) is more consistent than previously realized, particularly in Caucasian schizophrenia populations. We identified evidence for epistatic interaction between the associated SNPs at DAOA and DAO genes in contributing to schizophrenia risk (OR = 9.3 (1.4, 60.5). Based on these data, more systematic investigation of genes involved in DAO signaling is required.

Confirmation and refinement of an 'at-risk' haplotype for schizophrenia suggests the EST cluster, Hs.97362, as a potential susceptibility gene at the Neuregulin-1 locus.

Two recent association studies have implicated the neuregulin-1 gene (NRG1) at chromosome 8p21-22 as a susceptibility gene for schizophrenia. Stefansson et al identified three 'at-risk' haplotypes (HapA, B and C) which spanned the NRG1 locus and shared a common core haplotype. Subsequently, they demonstrated evidence that the core haplotype was associated with schizophrenia in an independent Scottish sample. To confirm and refine this haplotype we investigated the NRG1 locus in an independent Irish case-control sample. We did not find the core haplotype to be associated in our sample. However, we identified a refined 2-marker haplotype (HapB(IRE)) that shared common alleles with one of the Icelandic 'at-risk' haplotypes and is in significant excess in the Irish cases (19.4%) vs controls (12.3%) (P=0.013). This refined 'at-risk' haplotype is also in significant excess in the Scottish case sample (17.0% vs 13.5%; P=0.036). Interestingly, this refined 'at-risk' haplotype is positioned close to an EST cluster of unknown function (Hs.97362) within intron 1 of NRG1.

Interaction of animal cells with ordered nanotopography.

Animal cells live in a complex and diverse environment where they encounter a vast amount of information, a considerable amount of which is in the nanometer range. The surface topography that a cell encounters has a role to play in influencing cell behavior. It has been demonstrated widely that surface shape can directly influence the behavior of cells. In this paper, we discuss the interactions of animal cells with engineered nanotopography, fabricated in quartz and reverse embossed into polycaprolactone, fibroblast cells show reduced adhesion to the ordered nano pits. We show that the area of cells spreading on a structured nanotopography is reduced compared with that on a planar substrate. Furthermore, cytoskeletal organization is disrupted as indicated by a marked decrease in number and size of focal contacts.

Fat redistribution in indinavir-treated patients with HIV infection: A review of postmarketing cases.

CONTEXT: Fat redistribution (FR) occurring alone or in association with hyperlipidemia has been associated with protease inhibitors (PI) and nucleoside reverse transcriptase inhibitors (NRTIs); however, the relationship between FR features, relationship of FR to hyperlipidemia, and pathogenesis of FR is unknown. OBJECTIVE: To characterize the spectrum of FR, assess relationships among FR features, determine trends in occurrence of FR, and determine relationship of FR to hyperlipidemia. DESIGN: Review of postmarketing indinavir reports of FR in Merck & Co. Inc.'s database. SETTING AND PARTICIPANTS: 282 reports of FR among HIV-positive patients taking indinavir submitted through the passive postmarketing system to Merck through February 23, 1998. RESULTS: 282 FR reports were compared across 3 groups: fat accumulation (FA) only, FA with peripheral wasting (FA with PW), and peripheral wasting only (PWO). Of 282 reports, 56% (159 of 282) had FA only, 22% (63 of 282) had FA with PW, and 21% (60 of 282) had PWO. The proportions of reports of PWO was higher in men, whereas the proportion of reports of FA was higher in women. Blood lipids were provided in 93 of 282 reports; were elevated in 69 of 93, and were normal in 24 of 93 reports. Proportions of hyperlipidemia and hypertriglyceridemia reports were significantly higher in the PWO group versus FA only group (p =.024 and.003, respectively) and versus FA with/without PW groups (p =.038 and.005, respectively). Weight gain was more frequently reported in those with FA (100%) or FA with PW (68%), whereas weight loss was usually reported in those with PWO (83%). In all, 98% of patients reporting FR on indinavir for whom a concomitant drug history was available were also taking lamivudine, stavudine, or both. A higher proportion of patients reporting PWO (34 of 60; 56.7%) versus FA (42 of 159; 26.4%) only took both lamivudine and stavudine. CONCLUSIONS: Differences observed from analysis of cases in clinical features, gender, weight change, concomitant medications, and presence of hyperlipidemia among the three groups of FR cases reported to Merck suggests that PWO may be a distinct entity from other features of FR. The data suggest that certain antiretroviral combinations predispose HIV persons to development of FR.

Visual preferences of Mexican preschool children for abstract and realistic paintings.

51 Mexican children ages 3 and 4 years were asked to express preferences for 9 abstract and 9 realistic paintings on two separate occasions. Consistently, the children showed no clear preferences for abstract or realistic paintings and their choices remained stable. Implications for educational and cultural environments as well as children's literature are discussed.

Mupirocin-resistant Staphylococcus aureus in a specialist school population.

Staphylococcus aureus strains resistant to mupirocin (MIC > 4000 mg l-1) were recovered from children and staff at a school for children with eczema and/or asthma or cystic fibrosis after mupirocin had been used to treat eczematous lesions. At least three distinct strains of S. aureus were involved and resistance was shown to be due in most isolates to a transmissible plasmid. The need for monitoring the extended use of this valuable antibiotic is emphasized.

Visual preferences of preschool children for abstract and realistic paintings.

40 children ages 2 or 3 years were asked to express preferences for 9 abstract and 9 realistic paintings on two separate occasions. Children showed no clear preferences and these were stable over occasions. Their drawings were classified in the scribble stage. These results were consistent with downward extensions of aesthetic preference theories. Implications for the usual environments of young children were discussed.

Postpartum concerns of breastfeeding mothers.

PIP: Increased mobility of families and shorter hospital stays have added to the adjustment difficulties of new mothers, and lack of an adequate support system may cause the mother to end breast feeding. The purpose of this study was to identify the postpartum concerns of breast feeding mothers from time of discharge through the 1st postpartum month. The sample consisted of 32 women, aged 20-38, who had uncomplicated vaginal deliveries, were released from hospital by the 3rd day, and were breast feeding for the 1st time. They were telephoned daily during the 1st 2 weeks and twice a week for the 3rd and 4th week. 78% were primigravidas. 97% of the women reported a total of 210 concerns about the infant; 81% reported 237 concerns about themselves; and 19% reported 15 concerns about interactions with family or friends. Feeding-related concerns were most frequent in the 1st and 2nd weeks and included frequency of feeding (64%), formula and/or water supplementation, and duration of nursing time. Concerns about the infants' sleeping and crying behavior were also most frequent (76%) during the 1st 2 weeks. Sleeping concerns included the effects of long periods of wakefulness and sleeping during the day rather than at night. Crying or fussy behavior following feeding and during family dinner was reported by 53% of the mothers during the 1st week and 41% during the 2nd week. Concerns about the physical state of the infant included wellness and growth, temperature, cord care, bilirubin level, infection, and bowel movements. 81% of the mothers expressed concerns about themselves. Physical concerns included breast soreness, nipple pain and blisters, uterine bleeding and cramps, episiotomy pain, muscle pain, and hemorrhoids. 18 mothers reported emotional concerns, particularly fatigue. Only 6 mothers reported concern over interactions with family and friends, including lack of help from the father and pressure from visits by friends and relatives. The greatest number of concerns expressed in this study were related to the infant, whereas other studies have reported more maternal concerns. However, these women were all breast feeding, which may imply that they were more infant-oriented to begin with.^ieng

Toxicity and immunosuppressive activity of binary combinations of 2'-deoxycoformycin and 2'-deoxyadenosine.

Treatment of mice with 2'-deoxycoformycin (dCf) for 5 days produced inhibition of spleen and lymph node adenosine deaminase (E. C. 3.5.4.4) activity but no hematologic toxicity or weight loss. A 64-fold elevation of erythrocyte dATP was observed. However, if mice were injected with 2'-deoxyadenosine (AdR) in combination with dCf, weight loss, hematologic toxicity, and liver cell necrosis occurred. These mice had a severe blood coagulation defect and a 73-fold elevation of plasma alanine transaminase activity, plasma prealbumin became undetectable, and erythrocyte dATP levels were elevated 1500-fold. Death during treatment appeared to be from acute liver failure since bone marrow toxicity was only detected following termination of treatment. These effects were not seen in mice receiving adenosine in combination with dCf. dCf, either alone or in combination with AdR, inhibited the contact sensitization to oxazalone in mice. The inhibition was associated with signs of systemic toxicity which were more pronounced in the combination-treated groups. If dATP is the toxic metabolic accumulated in the malignant cells of patients treated with dCf, we propose that AdR supplementation of treatment should be considered with extreme caution since severe damage to normal tissues might result.