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.

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.

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.

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.

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.

[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.