Stick insect genomes reveal natural selection's role in parallel speciation.

Natural selection can drive the repeated evolution of reproductive isolation, but the genomic basis of parallel speciation remains poorly understood. We analyzed whole-genome divergence between replicate pairs of stick insect populations that are adapted to different host plants and undergoing parallel speciation. We found thousands of modest-sized genomic regions of accentuated divergence between populations, most of which are unique to individual population pairs. We also detected parallel genomic divergence across population pairs involving an excess of coding genes with specific molecular functions. Regions of parallel genomic divergence in nature exhibited exceptional allele frequency changes between hosts in a field transplant experiment. The results advance understanding of biological diversification by providing convergent observational and experimental evidence for selection's role in driving repeatable genomic divergence.

Aptitude à la conduite, pathologies psychiatriques et psychotropes chez la personne âgée [Driving ability, mental illness and psychotropic medication in the elderly].

Fitness to drive in elderly drivers is most commonly discussed with a focus on cognitive impairment. Therefore, this article is focussing on mental illness and the use of psychotropic drugs in elderly drivers, which can both interfere with fitness to drive. Based on a detailed literature review and on clinical judgement, we propose signposts and "red flags" to judge the individual risks. Health professionals dealing with elderly patients should in particular be aware of the dangers related to cumulative risks and need to inform the patients appropriately. For medico-legal reasons the information provided to patients must be written down in the medical record. Individual counselling is important as fitness to drive is a complex topic.

Impact of recommendation updates in well-controlled patients on nonrecommended antiretroviral therapies: the Swiss HIV cohort study.

BACKGROUND: HIV treatment recommendations are updated as clinical trials are published. Whether recommendations drive clinicians to change antiretroviral therapy in well-controlled patients is unexplored. METHODS: We selected patients with undetectable viral loads (VLs) on nonrecommended regimens containing double-boosted protease inhibitors (DBPIs), triple-nucleoside reverse transcriptase inhibitors (NRTIs), or didanosine (ddI) plus stavudine (d4T) at publication of the 2006 International AIDS Society recommendations. We compared demographic and clinical characteristics with those of control patients with undetectable VL not on these regimens and examined clinical outcome and reasons for treatment modification. RESULTS: At inclusion, 104 patients were in the DBPI group, 436 in the triple-NRTI group, and 19 in the ddI/d4T group. By 2010, 28 (29%), 204 (52%), and 1 (5%) patient were still on DBPIs, triple-NRTIs, and ddI plus d4T, respectively. 'Physician decision,' excluding toxicity/virological failure, drove 30% of treatment changes. Predictors of recommendation nonobservance included female sex [adjusted odds ratio (aOR) 2.69, 95% confidence interval (CI) 1 to 7.26; P = 0.01] for DPBIs, and undetectable VL (aOR 3.53, 95% CI 1.6 to 7.8; P = 0.002) and lack of cardiovascular events (aOR 2.93, 95% CI 1.23 to 6.97; P = 0.02) for triple-NRTIs. All patients on DBPIs with documented diabetes or a cardiovascular event changed treatment. Recommendation observance resulted in lower cholesterol values in the DBPI group (P = 0.06), and more patients having undetectable VL (P = 0.02) in the triple-NRTI group. CONCLUSION: The physician's decision is the main factor driving change from nonrecommended to recommended regimens, whereas virological suppression is associated with not switching. Positive clinical outcomes observed postswitch underline the importance of observing recommendations, even in well-controlled patients.

Use of a short hPDE6b promoter for rod gene transfer in a model of severe retinal cystrophy, the Rd10 mouse

Purpose: Gene therapy of severe retinal dystrophies directly affecting photoreceptor is still a challenge in terms of clinical application. One of the main hurdles is to generate high transgene expression specifically in rods or cones. In the present study, we are investigating the possibility to drive hPDE6b expression in the Rd10 mouse retina using a specific sequence of the human PDE6b promoter. Methods: Two 5' flanking fragments of the human PDE6b gene: (-93 to +53 (146 bp) and -297 to +53 (350 bp, see Di Polo and Farber, 1995) were cloned in different plasmids in order to check their expression in vitro and in vivo. These elements drove the activity of either luciferase (pGL3 plasmids) or EGFP (AAV2/8 backbone). Then, an AAV2/8 vector carrying the PDE6b cDNA was tested with subretinal injections at P9 in the Rd10 eyes. Eye fundus, OCT, ERG recordings and histological investigations were performed to assess the efficacy of the gene transfer. Results: The short PDE6b promoter containing 146bp (-93 to +53) showed the highest activity in the Y-79 cells, as described previously (Di Polo and Farber, 1995). Subretinal administrations of AAV2/8-PDE6bpromoter-EGFP allowed a rapid expression specifically in rods and not in cones. The expression is faster than a vector containing the CMV promoter. The AAV2/8-PDE6bpromoter-PDE6b and the control vector were injected at P9 in the Rd10 mouse retina and investigated 5 weeks post-injection. Out of 14 eyes, 6 presented an increased rod sensitivity of about 300 fold, and increased a- and b-wave responses in ERG recordings. Flicker stimulations revealed that cones are also functional. OCT images and histological analyses revealed an increased ONL size in the injected area. The retina treated with the therapeutic vector presented 4-6 rows of photoreceptors with outersegments containing PDE6b. In the control eyes, only 2-4 rows of photoreceptors with almost no OS were observed . Conclusions: The 146 bp promoter sequence (-93 to + 53) is the shortest regulatory element described to date which allows to obtain efficient rod-specific expression in the context of somatic gene transfer. This first result is of great interest for AAV vector design in general allowing more space for the accommodation of transgenes of interest and good expression in rods. Moreover we showed the proof of principle of the efficacy of AAV2/8-PDE6bp-PDE6b vector in the Rd10 mouse model of severe photoreceptor degeneration without using neither AAV mutated capsids, nor self-complementary vectors.

Phosphatidylethanolamine critically supports internalization of cell-penetrating protein C inhibitor.

Although their contribution remains unclear, lipids may facilitate noncanonical routes of protein internalization into cells such as those used by cell-penetrating proteins. We show that protein C inhibitor (PCI), a serine protease inhibitor (serpin), rapidly transverses the plasma membrane, which persists at low temperatures and enables its nuclear targeting in vitro and in vivo. Cell membrane translocation of PCI necessarily requires phosphatidylethanolamine (PE). In parallel, PCI acts as a lipid transferase for PE. The internalized serpin promotes phagocytosis of bacteria, thus suggesting a function in host defense. Membrane insertion of PCI depends on the conical shape of PE and is associated with the formation of restricted aqueous compartments within the membrane. Gain- and loss-of-function mutations indicate that the transmembrane passage of PCI requires a branched cavity between its helices H and D, which, according to docking studies, precisely accommodates PE. Our findings show that its specific shape enables cell surface PE to drive plasma membrane translocation of cell-penetrating PCI.

Sleep deprivation effects on circadian clock gene expression in the cerebral cortex parallel electroencephalographic differences among mouse strains.

Sleep deprivation (SD) results in increased electroencephalographic (EEG) delta power during subsequent non-rapid eye movement sleep (NREMS) and is associated with changes in the expression of circadian clock-related genes in the cerebral cortex. The increase of NREMS delta power as a function of previous wake duration varies among inbred mouse strains. We sought to determine whether SD-dependent changes in circadian clock gene expression parallel this strain difference described previously at the EEG level. The effects of enforced wakefulness of incremental durations of up to 6 h on the expression of circadian clock genes (bmal1, clock, cry1, cry2, csnk1epsilon, npas2, per1, and per2) were assessed in AKR/J, C57BL/6J, and DBA/2J mice, three strains that exhibit distinct EEG responses to SD. Cortical expression of clock genes subsequent to SD was proportional to the increase in delta power that occurs in inbred strains: the strain that exhibits the most robust EEG response to SD (AKR/J) exhibited dramatic increases in expression of bmal1, clock, cry2, csnkIepsilon, and npas2, whereas the strain with the least robust response to SD (DBA/2) exhibited either no change or a decrease in expression of these genes and cry1. The effect of SD on circadian clock gene expression was maintained in mice in which both of the cryptochrome genes were genetically inactivated. cry1 and cry2 appear to be redundant in sleep regulation as elimination of either of these genes did not result in a significant deficit in sleep homeostasis. These data demonstrate transcriptional regulatory correlates to previously described strain differences at the EEG level and raise the possibility that genetic differences underlying circadian clock gene expression may drive the EEG differences among these strains.

Biochemical, morphological and content characterization of synaptobrevin 2-expressing vesicles in astrocytes

Neuron-astrocyte reciprocal communication at synapses has emerged as a novel signalling pathway in brain function. Astrocytes sense the level of synaptic activity and, in turn, influence its efficacy through the regulated release of ''glio- transmitters'' such as glutamate, ATP or D-serine. A calcium- dependent exocytosis is proposed to drive the release of gliotransmitters but its existence is still debated. To shed light onto the mechanisms controlling the storage and the release of gliotransmitters and namely D-serine, we have developed a new method for the immunoisolation of synaptobrevin 2-positive vesicles from rat cortical astrocytes in culture. The purified organelles are clear round shape vesicles of excellent purity as judged by electron microscopy. Immunoblotting analysis revealed that isolated vesicles contain most of the major proteins already described for neuron-derived vesicles. In addition, we have analyzed the content for various amino acids of these vesicles by means of chiral capillary electro- phoresis coupled to laser-induced fluorescence detection and liquid chromatography coupled to mass spectrometry. Post- embedding immunogold labelling of the rat neocortex and hippocampus further revealed the expression of D-serine and glutamate in astrocyte processes contacting excitatory sy- napses. Our results provide significant support for the existence of secretory glial vesicles storing chemical substances like D- serine and glutamate and thus point to the co-release of amino acids by exocytosis in astrocytes.

Psychiatrie de l'enfant et de l'adolescent : une approche basée sur les preuves

L'approche basée sur les preuves, dérivée de I'evidence based medicine anglo-saxonne, offre une vision élargie de la pédopsychiatrie en permettant aux thérapeutes de s'extraire de la stricte soumission aux conclusions de la recherche pour donner à la pratique, dans une certaine mesure, la possibilité de valider des choix de prise en charge pluridisciplinaires. Alors que l'evidence based médecine s'est imposée dans la plupart des spécialités médicales, elle tarde à s'implanter en psychiatrie de l'enfant et de l'adolescent. Cet ouvrage fait donc le point sur les connaissances actuelles et propose une approche plus globale fondée sur les preuves. Les 13 chapitres qui le composent couvrent une grande partie des troubles pédopsychiatriques en y intégrant des sujets d'ouverture comme l'alliance thérapeutique, les soins sous contrainte ou les équipes mobiles. Un chapitre consacré aux médicaments psychotropes utilisés chez l'enfant et l'adolescent permet d'offrir un aperçu complet des moyens thérapeutiques à disposition pour chacun de ces troubles.

Testing for local adaptation in brown trout using reciprocal transplants.

ABSTRACT: BACKGROUND: Local adaptation can drive the divergence of populations but identification of the traits under selection remains a major challenge in evolutionary biology. Reciprocal transplant experiments are ideal tests of local adaptation, yet rarely used for higher vertebrates because of the mobility and potential invasiveness of non-native organisms. Here, we reciprocally transplanted 2500 brown trout (Salmo trutta) embryos from five populations to investigate local adaptation in early life history traits. Embryos were bred in a full-factorial design and raised in natural riverbeds until emergence. Customized egg capsules were used to simulate the natural redd environment and allowed tracking the fate of every individual until retrieval. We predicted that 1) within sites, native populations would outperform non-natives, and 2) across sites, populations would show higher performance at 'home' compared to 'away' sites. RESULTS: There was no evidence for local adaptation but we found large differences in survival and hatching rates between sites, indicative of considerable variation in habitat quality. Survival was generally high across all populations (55% +/- 3%), but ranged from 4% to 89% between sites. Average hatching rate was 25% +/- 3% across populations ranging from 0% to 62% between sites. CONCLUSION: This study provides rare empirical data on variation in early life history traits in a population network of a salmonid, and large-scale breeding and transplantation experiments like ours provide powerful tests for local adaptation. Despite the recently reported genetic and morphological differences between the populations in our study area, local adaptation at the embryo level is small, non-existent, or confined to ecological conditions that our experiment could not capture.

Can fisheries-induced evolution shift reference points for fisheries management?

Biological reference points are important tools for fisheries management. Reference points are not static, but may change when a population's environment or the population itself changes. Fisheries-induced evolution is one mechanism that can alter population characteristics, leading to "shifting" reference points by modifying the underlying biological processes or by changing the perception of a fishery system. The former causes changes in "true" reference points, whereas the latter is caused by changes in the yardsticks used to quantify a system's status. Unaccounted shifts of either kind imply that reference points gradually lose their intended meaning. This can lead to increased precaution, which is safe, but potentially costly. Shifts can also occur in more perilous directions, such that actual risks are greater than anticipated. Our qualitative analysis suggests that all commonly used reference points are susceptible to shifting through fisheries-induced evolution, including the limit and "precautionary" reference points for spawning-stock biomass, Blim and Bpa, and the target reference point for fishing mortality, F0.1. Our findings call for increased awareness of fisheries-induced changes and highlight the value of always basing reference points on adequately updated information, to capture all changes in the biological processes that drive fish population dynamics.

Linking life-history traits, ecology, and niche breadth evolution in north american eriogonoids (polygonaceae).

Abstract Macroevolutionary and microevolutionary studies provide complementary explanations of the processes shaping the evolution of niche breadth. Macroevolutionary approaches scrutinize factors such as the temporal and spatial environmental heterogeneities that drive differentiation among species. Microevolutionary studies, in contrast, focus on the processes that affect intraspecific variability. We combine these perspectives by using macroevolutionary models in a comparative study of intraspecific variability. We address potential differences in rates of evolution of niche breadth and position in annual and perennial plants of the Eriogonoideae subfamily of the Polygonaceae. We anticipated higher rates of evolution in annuals than in perennials owing to differences in generation time that are paralleled by rates of molecular evolution. Instead, we found that perennial eriogonoid species present greater environmental tolerance (wider climate niche) than annual species. Niche breadth of perennial species has evolved two to four times faster than in annuals, while niche optimum has diversified more rapidly among annual species than among perennials. Niche breadth and average elevation of species are correlated. Moreover, niche breadth increases more rapidly with mean species elevation in perennials than in annuals. Our results suggest that both environmental gradients and life-history strategy influence rates and patterns of niche breadth evolution.

A 338-bp proximal fragment of the glucose transporter type 2 (GLUT2) promoter drives reporter gene expression in the pancreatic islets of transgenic mice.

The high Km glucose transporter GLUT2 is a membrane protein expressed in tissues involved in maintaining glucose homeostasis, and in cells where glucose-sensing is necessary. In many experimental models of diabetes, GLUT2 gene expression is decreased in pancreatic beta-cells, which could lead to a loss of glucose-induced insulin secretion. In order to identify factors involved in pancreatic beta-cell specific expression of GLUT2, we have recently cloned the murine GLUT2 promoter and identified cis-elements within the 338-bp of the proximal promoter capable of binding islet-specific trans-acting factors. Furthermore, in transient transfection studies, this 338-bp fragment could efficiently drive the expression of the chloramphenicol acetyl transferase (CAT) gene in cell lines derived from the endocrine pancreas, but displayed no promoter activity in non-pancreatic cells. In this report, we tested the cell-specific expression of a CAT reporter gene driven by a short (338 bp) and a larger (1311 bp) fragment of the GLUT2 promoter in transgenic mice. We generated ten transgenic lines that integrated one of the constructs. CAT mRNA expression in transgenic tissues was assessed using the RNAse protection assay and the quantitative reverse transcribed polymerase chain reaction (RT-PCR). Overall CAT mRNA expression for both constructs was low compared to endogenous GLUT2 mRNA levels but the reporter transcript could be detected in all animals in the pancreatic islets and the liver, and in a few transgenic lines in the kidney and the small intestine. The CAT protein was also present in Langerhans islets and in the liver for both constructs by immunocytochemistry. These findings suggest that the proximal 338 bp of the murine GLUT2 promoter contain cis-elements required for the islet-specific expression of GLUT2.

Effect of hypoxia on cerebral blood flow regulation during rest and exercise : role of cerebral oxygen delivery on performance

Adequate supply of oxygen to the brain is critical for maintaining normal brain function. Severe hypoxia, such as that experienced during high altitude ascent, presents a unique challenge to brain oxygen (O2) supply. During high-intensity exercise, hyperventilation-induced hypocapnia leads to cerebral vasoconstriction, followed by reductions in cerebral blood flow (CBF), oxygen delivery (DO2), and tissue oxygenation. This reduced O2 supply to the brain could potentially account for the reduced performance typically observed during exercise in severe hypoxic conditions. The aims of this thesis were to document the effect of acute and chronic exposure to hypoxia on CBF control, and to determine the role of cerebral DO2 and tissue oxygenation in limiting performance during exercise in severe hypoxia. We assessed CBF, arterial O2 content (CaO2), haemoglobin concentration ([Hb]), partial pressure of arterial O2 (PaO2), cerebrovascular CO2 reactivity, ventilatory response to CO2, cerebral autoregulation (CA), and estimated cerebral DO2 (CBF ⨉ CaO2) at sea level (SL), upon ascent to 5,260 m (ALT1), and following 16 days of acclimatisation to 5,260 m (ALT16). We found an increase in CBF despite an elevated cerebrovascular CO2 reactivity at ALT1, which coincided with a reduced CA. Meanwhile, PaO2 was greatly decreased despite increased ventilatory drive at ALT1, resulting in a concomitant decrease in CaO2. At ALT16, CBF decreased towards SL values, while cerebrovascular CO2 reactivity and ventilatory drive were further elevated. Acclimatisation increased PaO2, [Hb], and therefore CaO2 at ALT16, but these changes did not improve CA compared to ALT1. No differences were observed in cerebral DO2 across SL, ALT1, and ALT16. Our findings demonstrate that cerebral DO2 is maintained during both acute and chronic exposure to 5,260 m, due to the reciprocal changes in CBF and CaO2. We measured middle cerebral artery velocity (MCAv: index of CBF), cerebral DO2, ventilation (VE), and performance during incremental cycling to exhaustion and 15km time trial cycling in both normoxia and severe hypoxia (11% O2, normobaric), with and without added CO2 to the inspirate (CO2 breathing). We found MCAv was higher during exercise in severe hypoxia compared in normoxia, while cerebral tissue oxygenation and DO2 were reduced. CO2 breathing was effective in preventing the development of hyperventilation-induced hypocapnia during intense exercise in both normoxia and hypoxia. As a result, we were able to increase both MCAv and cerebral DO2 during exercise in hypoxia with our CO2 breathing setup. However, we concomitantly increased VE and PaO2 (and presumably respiratory work) due to the increased hypercapnic stimuli with CO2 breathing, which subsequently contributed to the cerebral DO2 increase during hypoxic exercise. While we effectively restored cerebral DO2 during exercise in hypoxia to normoxic values with CO2 breathing, we did not observe any improvement in cerebral tissue oxygenation or exercise performance. Accordingly, our findings do not support the role of reduced cerebral DO2 in limiting exercise performance in severe hypoxia. -- Un apport adéquat en oxygène au niveau du cerveau est primordial pour le maintien des fonctions cérébrales normales. L'hypoxie sévère, telle qu'expérimentée au cours d'ascensions en haute altitude, présente un défi unique pour l'apport cérébral en oxygène (O2). Lors d'exercices à haute intensité, l'hypocapnie induite par l'hyperventilation entraîne une vasoconstriction cérébrale suivie par une réduction du flux sanguin cérébral (CBF), de l'apport en oxygène (DO2), ainsi que de l'oxygénation tissulaire. Cette réduction de l'apport en O2 au cerveau pourrait potentiellement être responsable de la diminution de performance observée au cours d'exercices en condition d'hypoxie sévère. Les buts de cette thèse étaient de documenter l'effet de l'exposition aiguë et chronique à l'hypoxie sur le contrôle du CBF, ainsi que de déterminer le rôle du DO2 cérébral et de l'oxygénation tissulaire comme facteurs limitant la performance lors d'exercices en hypoxie sévère. Nous avons mesuré CBF, le contenu artériel en oxygène (CaO2), la concentration en hémoglobine ([Hb]), la pression partielle artérielle en O2 (PaO2), la réactivité cérébrovasculaire au CO2, la réponse ventilatoire au CO2, et l'autorégulation cérébrale sanguine (CA), et estimé DO2 cérébral (CBF x CaO2), au niveau de la mer (SL), au premier jour à 5.260 m (ALT1) et après seize jours d'acclimatation à 5.260 m (ALT16). Nous avons trouvé des augmentations du CBF et de la réactivité cérébrovasculaire au CO2 après une ascension à 5.260 m. Ces augmentations coïncidaient avec une réduction de l'autorégulation cérébrale. Simultanément, la PaO2 était grandement réduite, malgré l'augmentation de la ventilation (VE), résultant en une diminution de la CaO2. Après seize jours d'acclimatation à 5.260 m, le CBF revenait autour des valeurs observées au niveau de la mer, alors que la réactivité cérébrovasculaire au CO2 et la VE augmentaient par rapport à ALT1. L'acclimatation augmentait la PaO2, la concentration en hémoglobine, et donc la CaO2, mais n'améliorait pas l'autorégulation cérébrale, comparé à ALT1. Aucune différence n'était observée au niveau du DO2 cérébral entre SL, ALT1 et ALT16. Nos résultats montrent que le DO2 cérébral est maintenu constant lors d'expositions aiguë et chronique à 5.260m, ce qui s'explique par la réciprocité des variations du CBF et de la CaO2. Nous avons mesuré la vitesse d'écoulement du sang dans l'artère cérébrale moyenne (MCAv : un indice du CBF), le DO2 cérébral, la VE et la performance lors d'exercice incrémentaux jusqu'à épuisement sur cycloergomètre, ainsi que des contre-la-montres de 15 km en normoxie et en hypoxie sévère (11% O2, normobarique) ; avec ajout ou non de CO2 dans le mélange gazeux inspiré. Nous avons trouvé que MCAv était plus haute pendant l'exercice hypoxique, comparé à la normoxie alors que le DO2 cérébral était réduit. L'ajout de CO2 dans le gaz inspiré était efficace pour prévenir l'hypocapnie induite par l'hyperventilation, qui se développe à l'exercice intense, à la fois en normoxie et en hypoxie. Nous avons pu augmenter MCAv et le DO2 cérébral pendant l'exercice hypoxique, grâce à l'ajout de CO2. Cependant, nous avons augmenté la VE et la PaO2 (et probablement le travail respiratoire) à cause de l'augmentation du stimulus hypercapnique. Alors que nous avons, grâce à l'ajout de CO2, efficacement restauré le DO2 cérébral au cours de l'exercice en hypoxie à des valeurs obtenues en normoxie, nous n'avons observé aucune amélioration dans l'oxygénation du tissu cérébral ou de la performance. En conséquence, nos résultats ne soutiennent pas le rôle d'un DO2 cérébral réduit comme facteur limitant de la performance en hypoxie sévère.

Altered expression of the transcription factor Mef2c during retinal degeneration in Rpe65-/- mice.

Purpose. To investigate the role of the myocyte enhancer factor 2 (Mef2) transcription factor family in retinal diseases, Mef2c expression was assessed during retinal degeneration in the Rpe65(-/-) mouse model of Leber's congenital amaurosis (LCA). Mef2c-dependent expression of photoreceptor-specific genes was further addressed. Methods. Expression of Mef2 members was analyzed by oligonucleotide microarray, quantitative PCR (qPCR) and in situ hybridization. Mef2c-dependent transcriptional activity was assayed by luciferase assay in HEK293T cells. Results. Mef2c was the only Mef2 member markedly downregulated during retinal degeneration in Rpe65(-/-) mice. Mef2c mRNA level was decreased by more than 2 fold at 2 and 4 months and by 3.5 fold at 6 months in retinas of Rpe65(-/-) mice. Downregulation of Mef2c at the protein level was confirmed in Rpe65(-/-) retinas. The decrease in Mef2c mRNA levels in the developing Rpe65(-/-) retinas, from post-natal day (P)13 onward, was concomitant with the decreased expression of the rod-specific transcription factors Nrl and Nr2e3. Nrl was further shown to drive Mef2c transcriptional activity, supporting a physiological role for Mef2c in the retina. In addition, Mef2c appeared to act as a transcriptional repressor of its own expression, as well as those of the retina-specific retinal G-protein coupled receptor (Rgr), rhodopsin and M-opsin genes. Conclusions. These findings highlight the early altered regulation of the rod-specific transcriptional network in Rpe65-related disease. They further indicate that Mef2c may act as a novel transcription factor involved in the development and the maintenance of photoreceptor cells.

Association of candidate genes with phenotypic traits relevant to anorexia nervosa.

This analysis is a follow-up to an earlier investigation of 182 genes selected as likely candidate genetic variations conferring susceptibility to anorexia nervosa (AN). As those initial case-control results revealed no statistically significant differences in single nucleotide polymorphisms, herein, we investigate alternative phenotypes associated with AN. In 1762 females, using regression analyses, we examined the following: (i) lowest illness-related attained body mass index; (ii) age at menarche; (iii) drive for thinness; (iv) body dissatisfaction; (v) trait anxiety; (vi) concern over mistakes; and (vii) the anticipatory worry and pessimism versus uninhibited optimism subscale of the harm avoidance scale. After controlling for multiple comparisons, no statistically significant results emerged. Although results must be viewed in the context of limitations of statistical power, the approach illustrates a means of potentially identifying genetic variants conferring susceptibility to AN because less complex phenotypes associated with AN are more proximal to the genotype and may be influenced by fewer genes. Copyright © 2011 John Wiley & Sons, Ltd and Eating Disorders Association.