QTL detection by multi-parent linkage mapping in oil palm (Elaeis guineensis Jacq.)

A quantitative trait locus (QTL) analysis designed for a multi-parent population was carried out and tested in oil palm (Elaeis guineensis Jacq.), which is a diploid cross-fertilising perennial species. A new extension of the MCQTL package was especially designed for crosses between heterozygous parents. The algorithm, which is now available for any allogamous species, was used to perform and compare two types of QTL search for small size families, within-family analysis and across-family analysis, using data from a 2 × 2 complete factorial mating experiment involving four parents from three selected gene pools. A consensus genetic map of the factorial design was produced using 251 microsatellite loci, the locus of the Sh major gene controlling fruit shell presence, and an AFLP marker of that gene. A set of 76 QTLs involved in 24 quantitative phenotypic traits was identified. A comparison of the QTL detection results showed that the across-family analysis proved to be efficient due to the interconnected families, but the family size issue is just partially solved. The identification of QTL markers for small progeny numbers and for marker-assisted selection strategies is discussed

Buprenorphine/naloxone versus methadone and lofexidine in community stabilisation and detoxification: A randomised controlled trial of low dose short-term opiate-dependent individuals

Buprenorphine/naloxone, methadone and lofexidine are medications with utility in the treatment of opiate withdrawal. We report the first randomised controlled trial to compare the effects of these two medications on withdrawal symptoms and outcome during opiate induction/stabilisation and detoxification. A double-blind randomised controlled trial was conducted in an outpatient satellite clinic of a specialist drug service. Eighty opiate dependent individuals meeting DSM-IV criteria for opiate dependence, using ? ½ g heroin smoked/chased or ¼ g heroin injected or ? 30mg methadone, with ? 3 years of opioid dependency, underwent a short-term opiate treatment programme involving induction/stabilisation on methadone 30mg or buprenorphine/naloxone 4mg/1mg, followed by detoxification (where the methadone group was assisted by lofexidine). The main outcome measures were urine drug screens for opiates and withdrawal and craving questionnaires. There were no overall differences in positive urine drug screens and drop-outs during any phase of the study. During induction/stabilisation, withdrawal symptoms subsided more slowly for buprenorphine/naloxone than for methadone, and craving was significantly higher in the buprenorphine/naloxone group (p<0.05, 95% confidence interval ?3.5, ?0.38). During detoxification, withdrawal symptoms were significantly greater and the peak of withdrawal was earlier for the methadone/lofexidine group than the buprenorphine/naloxone group (p<0.01, 95% confidence interval 3.0, 8.3). Methadone/lofexidine and buprenorphine/naloxone had comparable outcomes during rapid outpatient stabilisation and detoxification in low dose opiate users