Genomic screen for loci associated with tobacco usage in Mission Indians

Background  

The prevalence of tobacco usage in Native American adults and adolescents is higher than any other racial or ethnic group, yet biological risk and protective factors underlying tobacco use in this ethnic group remain unknown. A genome scan for loci associated with tobacco use phenotypes was performed with data collected from a community sample of Mission Indians residing in Southwest California.     

青蒿琥酯皮肤擦剂在小鼠和兔体内的药代动力学研究

将青蒿琥酯溶于苯二甲酸二甲酯,加适量氨酮制成皮肤擦剂。给兔脱毛后,皮肤涂抹此擦剂25mg/kg后,血药浓度达峰时间平均为2 h,峰浓度平均为1.80μg/ml。药物在兔体内平均驻留时间为3.54 h,清除半衰期约为2.46 h。给小鼠脱毛皮肤涂抹擦剂6.7,31.3和71.4 mg/kg,血药浓度在给药后0.5～4 h达高峰,峰浓度分别为0.82,2.05和7.11μg/ml,体内药物平均驻留时间为3.39,2.79及3.54 h,清除半衰期为2.35,1.93及2.45 h。可见,给兔及小鼠皮肤擦剂后,青蒿琥酯吸收良好,血药浓度维持时间较长。     

Is there a genetic susceptibility locus for Parkinson's disease on chromosome 22q13?

The cytochrome P450 mono-oxygenase gene, CYP2D6 on chromosome 22q13 (ch22q13), has been inconsistently associated with Parkinson's disease. Associations with CYP2D6 have either been absent altogether or have involved more than one polymorphism, many of which have the same metabolic effect on gene expression. We examined the association between CYP2D6 polymorphisms and Parkinson's disease in a case-control study and included 10 polymorphic dinucleotide repeat markers linked to CYP2D6 to determine whether the association was present or due to linkage disequilibrium. There was no association between any polymorphism of CYP2D6 and Parkinson's disease, but two of 10 dinucleotide repeat markers linked to CYP2D6 were associated with the disease. These results provide evidence to suggest that there may be an unidentified locus for susceptibility to Parkinson's disease that is in linkage disequilibrium with dinucleotide repeat markers mapping near CYP2D6 on ch22q13.     

Gene-lifecourse interaction for alcohol consumption in adolescence and young adulthood: five monoamine genes.

Association analysis has suggested that common sequence variants of genes that affect monoamine function can affect substance use and abuse. Demonstration of these associations has been inconsistent because of limited sample sizes and phenotype definition. Drawing on the life course perspective, we predicted a stronger association between the polymorphisms in 5HTT, DAT1, DRD4, DRD2, and MAOA and alcohol consumption in young adulthood than adolescence. This analysis tested for the gene-lifecourse interaction for the frequency of alcohol consumption in a nationally representative non-alcohol-dependent sample of 2,466 individuals that were visited during adolescence and young adulthood for four times between 1994 and 2002. All five genes are significantly associated with the frequency of alcohol consumption, with the genotype effects ranging 7%-20% of the mean score of alcohol consumption and their P values being 0.014, 0.0003, 0.003, 0.007, 0.005, and 0.003, respectively. The association is only observed in the life stage of young adulthood and not in adolescence. This analysis has demonstrated the potential usefulness of the life course perspective in genetic studies of human behaviors such as alcohol consumption.