Collecting Saliva by Mail for Genetic and Cotinine Analyses in Participants Recruited through the Internet

The authors assessed whether collection by mail of saliva and buccal cells for genetic analysis was feasible in participants recruited through the Internet. In 2003, 14,773 visitors of a smoking cessation website were invited by e-mail to take part in the study. Salivettes (plastic vials containing a cotton roll) were mailed to participants, for collection of saliva and buccal cells. Because of limited resources, the authors stopped recruitment when 392 participants (3% of 14,733) were registered. They received 315 saliva samples back (80% of 392). Salivary cotinine was analyzed in 145 daily smokers. Cotinine concentration could be assessed in 141 samples (97%) (range 0.7-899ng/ml, median 260ng/ml). DNA extraction was achieved in all the 285 samples in which it was attempted. Quality of DNA was assessed by optical density measurements and by polymerase chain reaction amplification of a gene coding for the α-4 nicotinic receptor, with the detection of a known polymorphism. Successful results were obtained in 235 samples (82% of 285). Thus collecting saliva by mail for cotinine and DNA analysis in participants recruited through the internet produced samples of good quality at a reasonable cost. This approach should be valuable for genetic epidemiology and pharmacogenetic researc

Linkage mapping of benign familial infantile convulsions (BFIC) to chromosome 19q

Benign familial infantile convulsions (BFIC) are an autosomal-dominant epileptic syndrome characterized by an age of onset within the first year of life. Although they were first reported in families of Italian descent, BFIC have also been described in non-Italian families. We have mapped the BFIC gene to chromosome 19 by linkage analysis in five Italian families with a maximum two-point lod score of 6.36 at D19S114; maximum multipoint lod scores >8 were obtained for the interval D19S250-D19S245. BFIC are therefore the third idiopathic partial epileptic syndrome to be mapped on the human genom

Effects of Process Parameters on an Inverse Concentrated Miniemulsion Flowing in a Microchannel

Emulsions are of great industrial interest due to their wide variety and end‐use properties. Microfluidics systems provide excellent control of transport phenomena. Hence, the influence of operating parameters on a concentrated inverse miniemulsion flowing in a microfluidic system was investigated. The feasibility of maintaining the emulsion in a microfluidic device was clearly demonstrated and the associated operating domain identified. Due to its influence on rheology, the effect of temperature on the droplet size distribution was quantified. Under specific conditions, a mass transfer phenomenon between the train of water drops and the smallest droplets of the emulsion was found, potentially explained by a difference in osmotic pressure between the two aqueous phases

Genome-wide scan for genes involved in bipolar affective disorder in 70 European families ascertained through a bipolar type I early-onset proband: supportive evidence for linkage at 3p14

Preliminary studies suggested that age at onset (AAO) may help to define homogeneous bipolar affective disorder (BPAD) subtypes. This candidate symptom approach might be useful to identify vulnerability genes. Thus, the probability of detecting major disease-causing genes might be increased by focusing on families with early-onset BPAD type I probands. This study was conducted as part of the European Collaborative Study of Early Onset BPAD (France, Germany, Ireland, Scotland, Switzerland, England, Slovenia). We performed a genome-wide search with 384 microsatellite markers using non-parametric linkage analysis in 87 sib-pairs ascertained through an early-onset BPAD type I proband (AAO of 21 years or below). Non-parametric multipoint analysis suggested eight regions of linkage with P-values<0.01 (2p21, 2q14.3, 3p14, 5q33, 7q36, 10q23, 16q23 and 20p12). The 3p14 region showed the most significant linkage (genome-wide P-value estimated over 10 000 simulated replicates of 0.015 [0.01-0.02]). After genome-wide search analysis, we performed additional linkage analyses with increased marker density using markers in four regions suggestive for linkage and having an information contents lower than 75% (3p14, 10q23, 16q23 and 20p12). For these regions, the information content improved by about 10%. In chromosome 3, the non-parametric linkage score increased from 3.51 to 3.83. This study is the first to use early-onset bipolar type I probands in an attempt to increase sample homogeneity. These preliminary findings require confirmation in independent panels of families

Monoamine oxidase a and tryptophan hydroxylase gene polymorphisms: are they associated with bipolar disorder?

Most of the candidate gene studies in bipolar disorder have focused on the major neurotransmitter systems that are influenced by drugs used in the treatment of this disorder. The monoamine oxidase A (MAOA) and the tryptophan hydroxylase (TPH1, TPH2) genes are two of the candidates that have been tested in a series of association studies using unrelated or family-based controls. This review summarizes the existing association studies regarding these genes. Most of these studies were based on the unrelated case-control design with samples of 50 to 600 subjects. Regarding MAOA, three meta-analyses with partially overlapping samples supported a modest effect of this gene in bipolar disorder in female Caucasians. However, as several studies could not replicate these findings, more work is necessary to demonstrate unequivocally the involvement of MAOA in bipolar disorder and establish the biological mechanism underlying the genetic association. With respect to TPH1 and TPH2, the majority of studies did not provide evidence for an association between these genes and bipolar disorder. The genes are more likely to be related to suicidal behavior than to bipolar disorde

La révolution génomique au service de la filière viande bovine

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La révolution génomique concerne aussi le bovin

Genomics has brought about in its wake a true biological revolution and can be applied to all areas of life sciences. Having sequenced the genomes of several different species, genomics techniques now allow us to study polymorphisms and the gene expression of proteins, enhancing our understanding of the biological functions of genes. The combined know-how of physicists and computer scientists, as well as of geneticists and physiologists is required to identify how genes control the dynamics of cell functions. Naturally enough, it is in the sphere of human medicine that the applications of genomics look most promising. Preventive and customized medicine, adapted to the genetic potential and to the way of life of each individual, will in all probability see the light of clay in the foreseeable future. in farm animals, there is no doubt that sequencing the bovine genome will give rise to new concepts and new molecular tools which will accelerate studies in bovine genomics. Comparing the bovine genome with that of other species, including humans, is also a potential source of huge progress for both human health and ruminant husbandry in general