Perceived Barriers to Physical Activity Among Youth Living in Rural and Urban Canadian Communities: A Nationally Representative Cross-Sectional Study

BACKGROUND

We used nationally representative data to explore associations among location of residence (rural/urban) and perceived barriers to physical activity (PA) in Canadian youth.

METHODS

We analyzed the 2017 Canadian Community Health Survey, Barriers to Physical Activity Rapid Response data for 12- to 17-year-old youth. Nine items from the survey assessing perceived barriers to PA were combined into 3 barrier domains: resources, motivational, and socioenvironmental. The likelihood of reporting barriers to PA based on rural-urban location was examined using survey-weighted binary logistic regression following a model fitting approach. Sociodemographic factors were modeled as covariates and tested in interaction with location. For each barrier domain, we derived the best-fitting model with fewest terms.

RESULTS

There were no location-specific effects related to reporting any barrier or motivation-related PA barriers. We found a sex by location interaction predicting the likelihood of reporting resource-related barriers. Rural boys were less likely to report resource-related barriers compared with urban boys (odds ratio [OR] = 0.42 [0.20, 0.88]). Rural girls were more likely to report resource-related barriers compared with boys (OR = 3.72 [1.66, 8.30]). Regarding socioenvironmental barriers, we observed a significant body mass index by location interaction demonstrating that rural youth with body mass index outside the "normal range" showed a higher likelihood of reporting socioenvironmental barriers compared with urban youth (OR = 2.38 [1.32, 4.30]). For urban youth, body mass index was unrelated to reporting socioenvironmental barriers (OR = 1.07 [0.67, 1.71]).

CONCLUSION

PA barriers are not universal among Canadian youth. Our analyses highlight the importance of testing interactions in similar studies as well as considering key sociodemographic characteristics when designing interventions.

Integration of sex/gender and utilization of ecological Momentary assessment of cognition in clinical populations: a scoping review

Objectives: We aimed to describe the methods of smartphone-based cognitive ecological momentary assessment designs in clinical populations, with an intention to evaluate how the role of sex and/or gender has been considered in the design and analyses, particularly including female-specific physiology. Methods: This scoping review was conducted based on JBI scoping review methodology. On March 2nd, 2023, we searched for literature across four databases. Screening of the results and data extraction were conducted in duplicate according to the a priori methods in the pre-registered protocol. Results: 31 articles were included in this review. Participants ranged in age from 15-85 years old with various clinical disorders. Prompts were given between 1-7 times per day for 7-84 days. Executive function was the most frequently assessed cognitive domain. Over half the studies (n = 17, 55%) did not investigate the effects of sex and/or gender, and only one study considered the impact of hormonal therapy. Many studies (n = 14, 45%) used sex and gender interchangeably or incorrectly. Conclusions: Studies varied in design, with heterogeneity in the reporting of methodological information. The lack of attention to sex/gender on neuropsychological outcomes can lead to confusion and contradiction regarding its potential impact on cognition in clinical populations. This may hinder the identification of effective interventions for those assigned female at birth who have been overlooked or considered indistinguishable from their male counterparts. Given the well-documented impact of sex/gender on cognition, it is essential that future neuropsychological research, especially EMA-based studies, prioritize investigating sex/gender to ensure better outcomes for all.

Work, travel, or leisure: comparing domain-specific physical activity patterns based on rural-urban location in Canada

BACKGROUND

Physical activity occurs across various domains including leisure/recreation, for transportation, or for work or household reasons. Rural and urban active living environments are characterized by different opportunities for physical activity within each domain which may translate into different patterns of behavior. The aim of this study was to compare rural-urban differences in physical activity across different domains, and explore interactions between sociodemographic factors, physical activity domains, and rurality.

METHODS

We used self-reported data collected across three physical activity domains (active transportation, recreation, occupational/household) and relevant sociodemographic variables from the Canadian Community Health Survey. Adjusting for sociodemographic factors, we did two separate cross-sectional analyses: 1) binary logistic regression to determine the odds of reporting any activity in each domain, and 2) ordinary least squares regression using the sub-samples reporting > 0 min per week of activity to compare how much activity was reported in each domain.

RESULTS

Our final survey weighted sample of Canadian adults (mean age 47.4 years) was n = 25,669,018 (unweighted n = 47,266). Rural residents were less likely to report any active transportation (OR = 0.59, 95% CI [0.51, 0.67], p < .0001). For recreational physical activity, rural males had lower odds (OR = 0.75, 95% CI [0.67, 0.83], p < .0001) and rural females had higher odds (OR = 1.19, 95% CI [1.08, 1.30], p = .0002) of reporting any participation compared to urban residents. Rural males (OR = 1.90, 95% CI [1.74, 2.07], p < .0001) and females (OR = 1.33, 95% CI [1.21, 1.46], p < .0001) had higher odds of reporting any occupational or household physical activity.

CONCLUSIONS

Urban residents tend to participate in more active transportation, while rural residents participate in more occupational or household physical activity. Location-based differences in physical activity are best understood by examining multiple domains and must include appropriate sociodemographic interactions, such as income and sex/gender.

God in body and space: Investigating the sensorimotor grounding of abstract concepts

Abstract concepts are defined as concepts that cannot be experienced directly through the sensorimotor modalities. Explaining our understanding of such concepts poses a challenge to neurocognitive models of knowledge. One account of how these concepts come to be represented is that sensorimotor representations of grounded experiences are reactivated in a way that is constitutive of the abstract concept. In the present experiment, we investigated how sensorimotor information might constitute GOD-related concepts, and whether a person’s self-reported religiosity modulated this grounding. To do so, we manipulated both the state of the body (i.e., kneeling vs. sitting) and the state of stimuli (i.e., spatial position on the screen) in two tasks that required conceptual categorization of abstract words. Linear Mixed Effects model fitting procedures were used to determine which manipulated factors best predicted response latency and accuracy in both tasks. We successfully replicated previous research demonstrating faster categorization of GOD-related words when they were presented at the top of the screen. Importantly, results demonstrated that the kneeling posture manipulation enhanced this effect, as did religiosity, as participants who scored higher in religiosity showed a greater effect of the posture manipulation on the speed with which word categorization occurred when those words were presented in the higher visuospatial presentation condition. Overall, we interpreted our findings to suggest that directly manipulating sensorimotor information can facilitate the categorization of abstract concepts, supporting the notion that this information in part constitutes the representation of abstract concepts.

Barriers to physical activity for adults in rural and urban Canada: A cross-sectional comparison

Background

Individual differences in physical activity behavior are associated with a collection of individual and environmental factors manifesting as barriers to participation. Understanding how barriers to physical activity differ based on sociodemographic characteristics can support identification and elimination of health inequities.

Objectives

To compare the odds of reporting individual and environmental barriers to physical activity in rural and urban adults, and explore interactions between rural-urban location and sociodemographic factors to characterize patterns in barriers to physical activity.

Design

Cross-sectional.

Methods

We analyzed the 2017 Canadian Community Health Survey Barriers to Physical Activity Rapid Response, with a final weighted sample of 24,499,462 (unweighted n=21,967). The likelihood of reporting each barrier domain based on rural-urban location was examined using binary logistic regression following a model-fitting approach with sociodemographic characteristics as covariates or interaction terms.

Results

Adjusting for sociodemographic factors, rural residents showed 85% higher odds of reporting at least one social or built environmental barrier (OR=1.85 [1.66, 2.07]). Compared to urban residents, rural residents showed significantly higher odds of reporting barriers to facility access (OR=4.15 [3.58, 4.83]) and a lack of social support to be active (OR=1.17 [1.04, 1.32]). Urban residents reported lower preference for physical activity, lower enjoyment of physical activity and lower confidence in their ability to regularly engage in physical activity. Interactions between socioeconomic status and location were identified related to enjoyment and confidence to be active. There was no effect of location on predicting the odds of reporting an individual resource-related variable (e.g., time, energy).

Conclusions

Despite being more likely than urban residents to prefer and enjoy physical activity, rural residents have fewer opportunities and receive less social support to be active. It is important to consider geographic location when characterizing barriers to physical activity and in the development of context-specific health promotion strategies.

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Rural residents have a higher odds of reporting social or built environmental barriers to physical activity.

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The most common environmental barrier for rural residents was lack of access to free or low-cost facilities.

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Urban residents reported a lower preference and enjoyment of physical activity.

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There was no rural-urban location-based difference in barriers related to time or costs to be active.

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It is important to consider geographic location and sex when characterising barriers to physical activity.

Reflections on Neurofeminism and Intersectionality Using Insights From Psychology

Intersectionality contends that sex/gender is constituted of and with other social categories, and that the social structures giving rise to inequality should be addressed in research. This is a powerful and important perspective from which to investigate the processes and consequences of social group memberships, one which has been overlooked by most neuroscientific research. In particular, neurofeminism, a field of critical neuroscience that challenges neuroscientific assumptions, methods and interpretations of data that reinforce sexism, has ignored intersectionality to date. In contrast, research in the field of psychology has been engaging with intersectionality for more than a decade. In reflecting on how intersectionality has advanced feminist research in psychology, this paper provides a critical analysis of potential novel research avenues for neurofeminism. We identify three main research themes guided by intersectionality. The first theme involves research centered on understanding the socio-structural causes of health inequalities experienced by individuals with intersecting marginalized social identities; the second concerns research addressing the psychological processing of social group memberships that underlies the enactment of systemic discriminatory practices; and the third theme comprises intersectionality research that aims to challenge psychological epistemology. Drawing parallels between the fields of psychology and neuroscience, we explore the potential benefits and risks of advancing an intersectionality-informed neurofeminism.

Likelihood of meeting physical activity guidelines in rural and urban adults: cross-sectional analysis of the Canadian Community Health Survey

OBJECTIVES

The goal of this study was to compare the odds of meeting physical activity (PA) guidelines among adults living in rural and urban areas of Canada.

METHODS

Data from the 2017 cycle of the Canadian Community Health Survey were analyzed using binomial logistic regression with a sample of 47,266 adults representing a survey-weighted total of 25,669,018. The odds of meeting PA guidelines were determined based on self-reported moderate-to-vigorous PA (<150 min per week or ≥150 min per week). Communities were categorized as urban or rural based on population size and density. Individual-level correlates included in the model were self-identified sex, age, body mass index, highest level of education, household income, perceived health, and sense of belonging to community.

RESULTS

Approximately 56.6% of rural and 59.3% of urban adults reported meeting recommended PA levels when location was examined as a sole predictor. The best-fit model adjusted for all individual-level factors showed a significant sex × location interaction. Males in rural communities were more likely to report meeting PA guidelines (odds = 0.90 or 47.4%) than males in urban areas (odds = 0.78 or 43.8%), whereas females living in rural communities (odds = 0.58 or 36.7%) were less likely to report meeting PA guidelines than females in urban areas (odds = 0.65 or 39.4%).

CONCLUSION

The association between rural-urban residence and meeting PA guidelines appears to be contingent on self-identified sex differences. Future work should explore how gender- and location-related variables interact to influence self-reported PA engagement.

A missense mutation in the FZD7 gene is associated with dilution of the red areas of the coat in Montbéliarde cattle

Recently, a new genetically autosomal recessive color phenotype emerged in the red pied bovine Montbéliarde breed. It is characterized by a dilution of the red areas of the coat and was denominated 'milca'. A genome-wide homozygosity scan of 106 cases followed by haplotype analysis revealed a candidate region within BTA2 between positions 89.95 and 91.63 Mb. Analysis of whole-genome sequence data generated from milca animals identified a strong candidate variant within the coding region of the Frizzled-7 gene (FZD7). This gene encodes for a G-protein coupled receptor for Wnt signaling proteins. The variant induces a glycine to alanine substitution in the second extracellular loop, p.(Gly414Ala). Cross-species amino acid alignments revealed that this glycine is conserved among orthologs and most paralogs, suggesting that it plays an important role in FZD function. In addition, genotyping data revealed that the mutant allele is restricted to the Montbéliarde breed, at a 3.7% frequency. All homozygous cows for the mutant allele exhibited the milca phenotype whereas all heterozygotes had no coat color defects. In conclusion, this study strongly suggests that, in cattle, a mutation of FZD7 alone is sufficient to cause a coat color phenotype without any strong other adverse effect.

Gonads and strife: Sex hormones vary according to sexual orientation for women and stress indices for both sexes

This study assessed sexual orientation and psychobiological stress indices in relation to salivary sex hormones as part of a well-validated laboratory-based stress paradigm. Participants included 87 healthy adults that were on average 25 years old who self-identified as lesbian/bisexual women (n=20), heterosexual women (n=21), gay/bisexual men (n=26), and heterosexual men (n=20). Two saliva samples were collected fifteen minutes before and fifteen minutes after exposure to a modified Trier Social Stress Test to determine testosterone, estradiol, and progesterone concentrations via enzyme-immune assaying. Mean sex hormones were further tested in association to stress indices related to cortisol systemic output (area under the curve with respect to ground) based on ten measures throughout the two-hour visit, allostatic load indexed using 21 biomarkers, and perceived stress assessed using a well-validated questionnaire. Results revealed that lesbian/bisexual women had higher overall testosterone and progesterone concentrations than heterosexual women, while no differences were found among gay/bisexual men in comparison to heterosexual men. Lesbian/bisexual women and heterosexual men showed positive associations between mean estradiol concentrations and allostatic load, while gay/bisexual men and heterosexual women showed positive associations between mean testosterone and cortisol systemic output. In summary, sex hormone variations appear to vary according to sexual orientation among women, but also as a function of cortisol systemic output, allostatic load, and perceived stress for both sexes.

Locally induced laminar convection in liquid nitrogen and silicone oils

We present an experimental study of a laminar convective phenomenon induced by a centimetric heater totally immersed in a liquid pool (Rayleigh number ranging from 10(4) to 10(7)). This local heating is observed to induce a laminar convection that differs from the classical Rayleigh-Bénard cells created by heating the whole bottom of the fluid: the convection pattern is no more periodic. In order to obtain a complete map of the velocity field, we use Particle Image Velocimetry technique. The vertical velocity between the counter-rotating convective cells is used as the relevant physical parameter to describe the phenomenon. The potential cooling applications of this problem lead us to choose liquid nitrogen as an experimental fluid. We thus compare the results obtained for various temperature gradients in liquid nitrogen with experiments performed at room temperature with silicone oils of various viscosities. The theoretical law for the maximal vertical velocity from classical Rayleigh-Bénard experiments is adapted to the specific geometry investigated by using a new definition for the characteristic wavelength. This length is studied and appears to be dependent on the liquid properties. We finally obtain a remarkable agreement between theory and experimental data.

Association between subjective and cortisol stress response depends on the menstrual cycle phase

The relation between the physiologic and subjective stress responses is inconsistently reported across studies. Menstrual cycle phases variations have been found to influence the psychophysiological stress response; however little is known about possible cycle phase differences in the relationship between physiological and subjective stress responses. This study examined the effect of menstrual cycle phase in the association between subjective stress and physiological response. Forty-five women in either the follicular (n=21) or the luteal phase of the menstrual cycle were exposed to a psychosocial stress task. Salivary cortisol, cardiovascular, and subjective stress were assessed throughout the experiment. Results revealed a significant group difference in the association between peak levels of cortisol and post task subjective stress. In women in the follicular phase a negative association was observed (r(2)=0.199, p=0.04), while this relation was positive in the group of women in the luteal phase (r(2)=0.227, p=0.02). These findings suggest a possible role of sex hormones in modulating the cortisol stress response function in emotion regulation.

Psychological, endocrine and neural responses to social evaluation in subclinical depression

This study aimed to identify vulnerability patterns in psychological, physiological and neural responses to mild psychosocial challenge in a population that is at a direct risk of developing depression, but who has not as yet succumbed to the full clinical syndrome. A group of healthy and a group of subclinically depressed participants underwent a modified Montreal Imaging Stress task (MIST), a mild neuroimaging psychosocial task and completed state self-esteem and mood measures. Cortisol levels were assessed throughout the session. All participants showed a decrease in performance self-esteem levels following the MIST. Yet, the decline in performance self-esteem levels was associated with increased levels of anxiety and confusion in the healthy group, but increased levels of depression in the subclinical group, following the MIST. The subclinical group showed overall lower cortisol levels compared with the healthy group. The degree of change in activity in the subgenual anterior cingulate cortex in response to negative evaluation was associated with increased levels of depression in the whole sample. Findings suggest that even in response to a mild psychosocial challenge, those individuals vulnerable to depression already show important maladaptive response patterns at psychological and neural levels. The findings point to important targets for future interventions.

Differentiating anticipatory from reactive cortisol responses to psychosocial stress

Most psychosocial stress studies assess the overall cortisol response without further identifying the temporal dynamics within hormone levels. It has been shown, however, that the amplitude of anticipatory cortisol stress levels has a unique predictive value for psychological health. So far, no "best practice" in how to investigate the anticipatory cortisol stress response has emerged. The goal of the current research was to develop a protocol that would allow for a sensitive and easy-to-implement laboratory-based investigation into anticipatory cortisol stress levels. We initially tested 26 healthy men in either an anticipation- or stress-only condition of the Trier Social Stress Test (TSST) to map the distinct timelines of anticipatory and reactive cortisol release profiles (study 1). Subsequently, we administered the TSST to 50 healthy men such that the cortisol responses to anticipatory and reactive stress components could be dissociated (study 2). In both studies we sampled saliva cortisol at high frequency (at baseline, during 10min of anticipation and during and after 10min of acute stress) and the current mood state pre- and post-stress. We found anticipatory responder rates of 20% and 40%, with peak anticipatory cortisol levels between 14 and 20min after onset of anticipation. Visible changes in reactive cortisol levels occurred only after the termination of the acute stressor. We conclude that the best practice to detect a maximum number of anticipatory responders in the TSST would be to extend the anticipation phase to 15min. In doing so, the anticipatory cortisol peak could be captured at a time-point of the actual stressor that is uninfluenced by reactive cortisol levels. Overall, we could reveal several features of anticipatory responders. Most importantly, there was a positive correlation between anticipatory and reactive stress responses. There was no association between anticipatory cortisol and alpha-amylase as well as subjective-psychological stress responses. Future studies will have to determine whether the anticipatory responders differ with respect to various stress-sensitive parameters like sex, personality, psychological wellbeing or chronic stress.

Effects of panel sex composition on the physiological stress responses to psychosocial stress in healthy young men and women

Men and women differ in regard to psychosocial stress responses. Biological and contextual factors are known to mediate these differences; however, few studies investigated their interaction. In the present study, we examined contributions of both contextual and biological factors to the stress response of young healthy adults. Men and women were exposed to a modified version of Trier Social Stress Test. The participants gave a speech in front of a panel of judges, composed of either male or female panelists. Both men, and women presented a cortisol increase only when exposed to opposite sex panelists. Interestingly, this effect was only observed in women in their follicular phase. This finding showed that the induction of a psychosocial stress response does not strictly rely on direct social evaluation, but also depends on the sex composition of the panel. Implications for future studies are discussed.

Investigation into the cross-correlation of salivary cortisol and alpha-amylase responses to psychological stress

Stress is a multidimensional construct. To accurately represent stress physiology, multiple stress measures across multiple stress-related systems should be assessed. However, associations may be masked given that different systems underlie different time courses. Salivary cortisol and alpha-amylase (sAA) are reliable biological stress markers of the sympathetic nervous system (SNS) and the hypothalamus pituitary adrenal (HPA) axis, respectively. Studies examining the link between sAA and cortisol levels in response to stress have produced inconsistent results. Here, we investigated whether the covariance of stress-induced sAA and cortisol release is dependent on the distinct temporal dynamics of the two stress markers. A total of 50 male participants were exposed to a psychological laboratory stressor with high frequency (2-min interval) saliva sampling in two independent studies. Synchronized time series of sAA and cortisol measures before, during and after stress induction were obtained. Cross-correlation analysis was applied to test for the association of sAA and cortisol levels at various stages relative to the onset of the stressor. Positive and negative cross-correlations between lagged pairs of sAA and cortisol measures were found in both studies. The strongest correlation was found for sAA preceding cortisol release by 13.5 min (r = .27, p < .001). With a smaller effect size cortisol also significantly preceded sAA by 13.5 min (r = -.16, p < .001). We suggest that sAA and cortisol stress responses are reliably associated at various time lags throughout a stressful situation. As a possible connection site between HPA axis and SNS that may underlie sAA-cortisol associations, we discuss CRF neurons of the hypothalamus involved in sympathetic regulation.

Perceived early-life maternal care and the cortisol response to repeated psychosocial stress

BACKGROUND

In the past decade, a body of animal and human research has revealed a profound influence of early-life experiences, ranging from variations in parenting behaviour to severe adversity, on hypothalamic-pituitary-adrenal axis regulation in adulthood. In our own previous studies, we have shown how variations in early-life parental care influence the development of the hippocampus and modify the cortisol awakening response.

METHODS

In the present study, we investigated the influence of early-life maternal care on cortisol, heart rate and subjective psychological responses to the repeated administration of a psychosocial laboratory stressor in a population of 63 healthy young adults. Low, medium and high early-life maternal care groups were identified using the Parental Bonding Instrument.

RESULTS

Controlling for the effect of sex, we found an inverted u-shaped relation between increasing levels of maternal care and cortisol stress responsivity. Specifically, overall and stress-induced cortisol levels went from below normal in the low maternal care, to normal in the medium care, back to below normal in the high maternal care groups. We found no group differences with respect to heart rate and subjective psychological stress measures. Whereas low and high maternal care groups exhibited similarly low endocrine stress responses, their psychological profiles were opposed with increased levels of depression and anxiety and decreased self-esteem in the low care group.

LIMITATIONS

Sex was unequally distributed among maternal care groups, whereby the number of men with low maternal care was too small to allow introducing sex as a second between-group variable.

CONCLUSION

We discuss the potential significance of this dissociation between endocrine and psychological parameters with respect to stress vulnerability and resistance for each maternal care group.

Measuring indices of lifelong estrogen exposure: self-report reliability

OBJECTIVE

The utility of clinical markers of lifelong estrogen exposure is established in the understanding of breast cancer, osteoporosis and dementia, among others. However, a good number of studies rely on self-reports to ascertain the involvement of certain estrogen exposure indices. The goal of this study is to assess the reliability of self-reported lifelong estrogen exposure indices by measuring correlation between two repeats.

METHODS

A questionnaire assessing lifelong indices of estrogen exposure was developed (revised version included) and completed by 36 healthy postmenopausal women twice within a 4-year interval (age range from 50 to 79 years). Reliability was tested using Pearson's correlation coefficient.

RESULTS

Strong significant correlations were observed for most estrogen exposure indices and an effect of age was revealed. Age at menopause and age at initiation of hormone therapy were the two variables leading to weaker correlations across time of measurements; no relation was found between Time 1 and Time 2 when looking at the group of older women (over 65 years of age).

CONCLUSIONS

Overall, these results support the use of self-reported measures for most of the lifelong estrogen exposure indices, but they also warn us about the pitfalls of the climacteric period. However, the design of the current study did not allow us to test accuracy; thus, the validity of these self-reported variables needs to be addressed in the future.

A Generalized Caprine-like Hypoplasia Syndrome is localized within a 6-cM interval on bovine chromosome 13 in the Montbéliarde breed

Caprine-like Generalized Hypoplasia Syndrome (or SHGC) is a new hereditary disorder described in the Montbéliarde breed. We report here the characterization of this new disease, based on the visual examination of animals affected by SHGC, and on physiological and biochemical studies undertaken on samples of both SHGC and normal animals. Biological samples for more than 150 affected calves and their parents have been collected over the past 4 years within the framework of the Bovine Genetic Disease Observatory. First, pedigree analyses showed that the mode of inheritance is most probably autosomal recessive. Then, a genome scan with 113 animals and 140 microsatellite markers revealed a single locus within a 35-cM region on bovine chromosome 13. Genotypes of 261 animals for 18 new microsatellite markers from the region confirmed the localization of the disorder to a 6-cM interval. Finally, based on the analysis of haplotypes in 463 Montbéliarde sires, we estimated the frequency of the SHGC mutated allele in the population and could propose a strategy for the systematic eradication of this disorder in the near future.

Influence of maternal lipid profile on placental protein expression of LDLr and SR-BI

Maternal hyperlipidemia is a characteristic feature during pregnancy, it has been reported that modification of the maternal lipid profile can induce disturbance during pregnancy. In this study, we evaluated the impact of maternal lipid profile on the placental protein expression of two major receptors in cholesterol metabolism, the low density lipoprotein receptor (LDLr) and the scavenger receptor type B1 (SR-B1). We demonstrate an increase in the level of maternal total circulating cholesterol leads to a significant decrease in the level of the LDLr protein expression, while the level of the SR-BI expression remains unchanged. A similar change, for LDLr, is observed in association with the maternal pre-pregnancy body mass index and weight gain. Our data suggest that the LDLr plays a role in regulating cholesterol delivered to the baby from the placenta.

Identification of a doublet missense substitution in the bovine LRP4 gene as a candidate causal mutation for syndactyly in Holstein cattle

Syndactyly in Holstein cattle is an autosomal recessive abnormality characterized by the fusion of the functional digits. This disorder has been previously mapped to the telomeric part of bovine chromosome 15. Here, we describe the fine-mapping of syndactyly in Holstein cattle to a 3.5-Mb critical interval using a comparative mapping approach and an extended pedigree generated by embryo transfer. We report genetic evidence for the exclusion of two genes previously suggested as candidates (EXT2 and ALX4) and describe the identification of a doublet mutation in complete linkage disequilibrium with syndactyly in one gene of the critical interval: LRP4. Finally, based on recent discoveries concerning the mouse mutants dan and mdig and a mouse knockout for Lrp4, we present solid evidence that the subsequent substitution in LRP4 exon 33 is a strong candidate causal mutation for syndactyly in Holstein cattle.

Radiation hybrid mapping of genes and newly identified microsatellites in candidate regions for bovine arthrogryposis-palatoschisis and progressive ataxia based on comparative data from man, mouse and rat

A comparative pathology and mapping strategy was used to initiate a study on two bovine genetic diseases: arthrogryposis-palatoschisis and progressive ataxia, which affect mainly Charolais cattle. Bibliographic studies provided information on the pathology of these diseases, which helped to define similar diseases in other species. Animals affected by bovine arthrogryposis-palatoschisis display similar symptoms to those of muscular dysgenesis, mouse mutants and animals with progressive ataxia to those of Long Evans Shaker rat mutants. Candidate regions are respectively human chromosome 1q32 (BTA16) containing the gene CACNA1S and human chromosome 18q23 (BTA24) containing the gene myelin basic protein (MBP). Primer pairs were designed for 15 loci around each candidate gene, in a region of about 20 megabases and were used to screen a bovine Bacterial Artificial Chromosome (BAC) library. Eighteen microsatellites were found in the identified BAC clones, 11 on BTA24 and seven on BTA16. The genes and microsatellites were mapped by radiation hybrid (RH) analysis and a RH map was obtained for each region with 18 new localizations on BTA16 and 23 on BTA24. Comparative human-bovine analysis of the MBP region shows a good conservation of gene order while that of the CACNA1S region shows several breakpoints.

Founder TIGR/myocilin mutations for glaucoma in the Québec population

Primary open-angle glaucoma (POAG) is a complex disorder characterized by a progressive and treatable degeneration of the optic nerve. TIGR/myocilin (MYOC) gene mutations are found in approximately 4% of all POAG patients. Populations with frequent founder effects, such as the French-Canadians, offer unique advantages to implement genetic testing for the disorder. To assess molecular diagnosis for POAG in this population, we determined the prevalence of TIGR/MYOC mutations in 384 unrelated glaucoma patients, 38 ocular hypertensive subjects and 18 affected families (180 patients). We further analyzed the clinical features associated with these variations. Nine coding sequence variants were defined as mutations causing mostly, but not exclusively, POAG. Four families segregated distinct mutations (Gly367Arg, Gln368Stop, Lys423Glu and Pro481Leu), while 14 unrelated glaucoma patients harbored six known mutations (Thr293Lys, Glu352Lys, Gly367Arg, Gln368Stop, Lys423Glu and Ala445Val) and two novel (Ala427Thr and Arg126Trp). The frequencies of these mutations were respectively 3.8% and 22.2% in the unrelated and family studies. The Gly367Arg and Lys423Glu variants caused the earliest ages at onset. When achievable, assessment of relatives of unrelated mutation carriers showed the Arg126Trp and Gly367Arg to be familial. Characteristic allele signatures, indicative of specific founder effects, were observed for five of the six mutations conveyed by at least two patients. Recombination probability estimates suggested that the French-Canadian population had most probably inherited these six mutations from 7-10 Québec settlers. Our data demonstrated that genetic screening for TIGR/MYOC mutations should be offered to glaucoma families and to close relatives of unrelated patients aware of a family history for the disorder.

DNA analysis of abortion material assisted by histology screening

In cases of rape leading to fertilization, paternity testing can retrospectively identify the assailant. Abortion material commonly represents a mixture of maternal and fetal tissue and blood, which cannot be differentiated with the naked eye. Consequently, DNA typing of abortion material may be complicated, including band overlap if maternal tissue predominates. Therefore, histology screening of the abortion content for typical fetal tissue components, such as chorionic villi, followed by selected DNA typing of this sample is suggested. This combined approach is illustrated by a selected case demonstrating the reliability and concurrence of the histology and genetic results.

Paget disease of bone: mapping of two loci at 5q35-qter and 5q31

Paget disease of bone is characterized by focal increases of the bone-remodeling process. It is the second most common metabolic bone disease after osteoporosis. Genetic factors play a major role in the etiology of Paget disease of bone, and two loci have been mapped for the disorder: PDB1 and PDB2. The gene(s) causing the typical form of the disorder remains to be characterized. To decipher the molecular basis of Paget disease of bone, we performed genetic linkage analysis in 24 large French Canadian families (479 individuals) in which the disorder was segregating as an autosomal dominant trait. After exclusion of PDB2, a genomewide scan was performed on the three most informative family nuclei. LOD scores >1.0 were observed at seven locations. The 24 families were then used to detect strong evidence for linkage to chromosome 5q35-qter. Under heterogeneity, a maximum LOD score of 8.58 was obtained at D5S2073, at straight theta= .1. The same characteristic haplotype was carried by all patients in eight families, suggesting a founder effect. A recombination event in a key family confined the disease region within a 6-cM interval between D5S469 and the telomere. The 16 other families, with very low conditional probability of linkage to 5q35-qter, were further used, to map a second locus at 5q31. Under heterogeneity, a maximum LOD score of 3.70 was detected at D5S500 with straight theta=.00. Recombination events refined the 5q31 region within 12.2 cM, between D5S642 and D5S1972. These observations demonstrate the mapping of two novel loci for Paget disease of bone and provide further evidence for genetic heterogeneity of this highly prevalent disorder. It is proposed that the 5q35-qter and 5q31 loci be named "PDB3" and "PDB4," respectively.

[Therapy of the feeling.]

The authors present a new form of therapy which succeeds>> they say, because it is a way of life. After explaining the origins of this therapy>> bom from the therapists* need to be themselves>> they present the psychopathological theory of disorder>> rooted in the child's reception of inappropriate responses to his expression of feeling. They then explain the five-stage cycle of feeling: The Actual feeling-level; the sensation of defenses; the sensation of the defense-creating events; the patient acting in a new manner; the patient living at a new feeling-level. Next presented is the therapeutic community based on affective ties>> as well as the concepts of co-therapy (patients help each other) and the "break thru" dream>> in which process is emphasized.