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Genetic Impact (genetic + impact)
Selected AbstractsSpousal Concordance for Alcohol Dependence: Evidence for Assortative Mating or Spousal Interaction Effects?ALCOHOLISM, Issue 5 2007Julia D. Grant Background: Alcohol dependence (AD) is among the most common psychiatric disorders, and impacts the health and well-being of problem drinkers, their family members, and society as a whole. Although previous research has consistently indicated that genetic factors contribute to variance in risk for AD, little attention has been paid to nonrandom mating for AD. When assortative mating occurs for a heritable trait, spouses are genetically correlated and offspring are at increased risk of receiving high-risk genes from both parents. The primary goal of the present analyses is to test hypotheses about the source(s) and magnitude of spousal associations for AD using a twin-spouse design. Methods: DSM-IV AD (without the clustering criterion) was assessed via telephone interview for 5,974 twin members of an older cohort of the Australian Twin Register (born 1902,1964) and 3,814 spouses of the twins. Quantitative genetic modeling was used to determine the extent to which variability in risk for AD was influenced by genetic factors, the extent of spousal association for AD, and whether the association was attributable to assortative mating, reciprocal spousal interaction, or both processes. Results: Genetic factors explained 49% of the variance in risk for AD. There was no evidence of gender differences in the spousal interaction effect, the degree of rater bias, or the association between the twin's report of spouse AD and the spouse's AD phenotype. Either the assortative mating parameter or the spousal interaction parameter could be removed from the model without a significant decrement in fit, but both could not be dropped simultaneously, suggesting a lack of power to differentiate between these 2 causes of spousal correlation. When both effects were included in the model, the spousal correlation was 0.29, the assortative mating coefficient was 0.45 (i.e., "like marries like"), and the reciprocal spousal interaction coefficient was ,0.10 (i.e., after controlling for assortative mating, the additional impact of spousal interactions is slightly protective). Conclusions: These analyses provide evidence of significant spousal associations for AD, with assortative mating increasing spouse similarity and spousal interaction effects decreasing it after controlling for assortative mating. Although the genetic impact is modest, assortative mating results in an increased proportion of offspring exposed to 2 alcoholic parents and the associated detrimental environmental sequelae, and increases the likelihood of offspring inheriting high-risk genes from both parents. [source] Genetic polymorphism of CCR2-64I increased the susceptibility of hepatocellular carcinoma,JOURNAL OF SURGICAL ONCOLOGY, Issue 3 2010Chao-Bin Yeh MD Abstract Background and Objectives The purpose of this study was to investigate genetic impact of monocyte chemoattractant protein-1 (MCP-1) and its receptor chemokine receptor-2 (CCR2) gene polymorphisms on the susceptibility and clinicopathological characteristics of hepatocellular carcinoma (HCC). Methods A total of 446 subjects, including 344 healthy controls and 102 patients with HCC, were recruited in this study and subjected to PCR-RFLP to estimate the impact of these two polymorphic variants on HCC. Results No relationship between MCP-1 ,2518G/A gene polymorphism and HCC risk was found among our recruited HCC patients and healthy controls. However, there was a significantly increased risk (AOR,=,1.91; 95% CI,=,1.11,3.29) of having HCC among subjects with GA heterozygotes of CCR2 V64I after adjusting for other confoundings. There was no synergistic effect between gene polymorphism and environmental risk factors, including tobacco and alcohol consumptions, as well as clinicopathological parameters of HCC for MCP-1 ,2518G/A and CCR2 V64I genes, respectively. Conclusions CCR2-64I gene polymorphism is an important factor for the susceptibility of HCC but it might not influence the clinical pathological progression of HCC, and the contribution of CCR2-64I gene polymorphism on the susceptibility of HCC could be not through the affection of liver injury-related clinical pathological characteristics. J. Surg. Oncol. 2010;102:264,270. © 2010 Wiley-Liss, Inc. [source] The genetic impact of demographic decline and reintroduction in the wild boar (Sus scrofa): A microsatellite analysisMOLECULAR ECOLOGY, Issue 3 2003C. Vernesi Abstract The reintroduction of wild boar from central Europe after World War II has contributed substantially to the range expansion of this species in Italy, where indiscriminate hunting in earlier times resulted in extreme demographic reduction. However, the genetic impact of such processes is not well-understood. In this study, 105 individuals from Italian and Hungarian wild boar populations were characterized for nine autosomal microsatellite loci. The Hungarian samples, and two central Italian samples from protected areas (parks) where reintroduction is not documented, were assumed to be representative of the genetic composition of the source and the target populations in the reintroduction process, respectively. Animals hunted in the wild in the Florence area of Tuscany (Italy) were then studied to identify the effects of reintroduction. The results we obtained can be summarized as follows: (i) none of the populations analysed shows genetic evidence of demographic decline; (ii) the three parental populations from Italy and Hungary are genetically distinct; however, the low level of divergence appears in conflict with the naming of the Italian and the European subspecies (Sus scrofa majori and Sus scrofa scrofa, respectively); in addition, the Italian groups appear to be as divergent from each other as they are from the Hungarian population; (iii) most of the individuals hunted near Florence are genetically intermediate between the parental groups, suggesting that hybridization has occurred in this area, the average introgression of Hungarian genotypes is 13%, but , 45% of the genetic pool of these individuals can not be directly attributed to any of the parental populations we analysed; (iv) analysis of microsatellite loci, though in a limited number, is an important tool for estimating the genetic effect of reintroduc ion in the wild boar, and therefore for the development of conservation and management strategies for this species. [source] Haploid chromosomes in molecular ecology: lessons from the human YMOLECULAR ECOLOGY, Issue 7 2001Matthew E. Hurles Abstract We review the potential use of haploid chromosomes in molecular ecology, using recent work on the human Y chromosome as a paradigm. Chromosomal sex-determination systems, and hence constitutively haploid chromosomes, which escape from recombination over much of their length, have evolved multiple times in the animal kingdom. In mammals, where males are the heterogametic sex, the patrilineal Y chromosome represents a paternal counterpart to mitochondrial DNA. Work on the human Y chromosome has shown it to contain the same range of polymorphic markers as the rest of the nuclear genome and these have rendered it the most informative haplotypic system in the human genome. Examples from research on the human Y chromosome are used to illustrate the common interests of anthropologists and ecologists in investigating the genetic impact of sex-specific behaviours and dispersals, as well as patterns of global diversity. We present some methodologies for extracting information from these uniquely informative yet under-utilized loci. [source] Genetic variation in remnant Festuca hallii populations is weakly differentiated, but geographically associated across the Canadian PrairiePLANT SPECIES BIOLOGY, Issue 3 2009JIE QIU Abstract Genetic diversity is essential for predicting plant evolutionary potential and for formulating conservation strategies. However, little is known about the genetic variation of plains rough fescue [Festuca hallii (Vasey) Piper], a widespread and diagnostic grass in the Fescue Prairie. We used the amplified fragment length polymorphism (AFLP) technique to assess the genetic variation of 30 fragmented populations of F. hallii across the northern Canadian Prairie and its associations with 12 geographical, fragmentation and environmental attributes. Three AFLP primer pairs were used to screen 840 samples, representing approximately 30 samples from each population, and 246 polymorphic bands were scored. The fescue plant was genetically diverse, as revealed by the proportion of polymorphic bands (0.870,0.967), the mean band frequency (0.364,0.457) and the within-population variation (69.4,85.4). The genetic variation was not highly differentiated, with only 6.5% of the total AFLP variation residing among populations. A Mantel test revealed a significant correlation between genetic and geographical distances (r = 0.39; P < 0.004) and a spatial autocorrelation up to 60 km among populations was detected. The AFLP variation displayed a longitudinal decline and was significantly associated with environmental attributes related to moisture, indicating local adaptation. However, the AFLP variation was not significantly associated with the estimated population size and geographical distance to the nearest neighbor, suggesting that fragmentation has not generated considerable genetic impact on the fescue populations. Implications for fescue conservation, restoration and management are discussed. [source] Genetic and environmental influences on the transmission of parental depression to children's depression and conduct disturbance: an extended Children of Twins studyTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 6 2010Judy L. Silberg Background:, Despite the increased risk of depression and conduct problems in children of depressed parents, the mechanism by which parental depression affects their children's behavioral and emotional functioning is not well understood. The present study was undertaken to determine whether parental depression represents a genuine environmental risk factor in children's psychopathology, or whether children's depression/conduct can be explained as a secondary consequence of the genetic liability transmitted from parents to their offspring. Methods:, Children of Twins (COT) data collected on 2,674 adult female and male twins, their spouses, and 2,940 of their children were used to address whether genetic and/or family environmental factors best account for the association between depression in parents and depression and conduct problems in their children. Data collected on juvenile twins from the Virginia Twin Study of Adolescent Behavioral Development (VTSABD) were also included to estimate child-specific genetic and environmental influences apart from those effects arising from the transmission of the parental depression itself. The fit of alternative Children of Twin models were evaluated using the statistical program Mx. Results:, The most compelling model for the association between parental and juvenile depression was a model of direct environmental risk. Both family environmental and genetic factors accounted for the association between parental depression and child conduct disturbance. Conclusions:, These findings illustrate how a genetically mediated behavior such as parental depression can have both an environmental and genetic impact on children's behavior. We find developmentally specific genetic factors underlying risk to juvenile and adult depression. A shared genetic liability influences both parental depression and juvenile conduct disturbance, implicating child conduct disturbance (CD) as an early indicator of genetic risk for depression in adulthood. In summary, our analyses demonstrate differences in the impact of parental depression on different forms of child psychopathology, and at various stages of development. [source] Role of interleukin-17F in chronic inflammatory and allergic lung diseaseCLINICAL & EXPERIMENTAL ALLERGY, Issue 9 2006N. Hizawa Summary IL-17 family members belong to a distinct category of cytokines that coordinate local tissue inflammation by inducing the release of pro-inflammatory and neutrophil-mobilizing cytokines. The importance of the IL-17 family in inflammatory and autoimmune disease is becoming increasingly apparent. IL-17F is a recently discovered member of the IL-17 family that has a number of biological activities through induction of various cytokines, chemokines, and mediators. IL-17A, the founding member of the IL-17 family, and IL-17F are produced by several inflammatory cells, including activated T cells, in response to infectious and antigenic stimuli. Overexpression of IL-17A or IL-17F in the lungs results in induction of CXC chemokines and neutrophil recruitment. In a case,control study of 1125 unrelated Japanese subjects, a His161 to Arg161 (H161R) substitution in the third exon of the IL17F gene was shown to be associated with asthma and chronic obstructive pulmonary disease (COPD). Functionally, this variant failed to induce cytokines and chemokines, and interestingly, was able to antagonize the activity of wild-type IL-17F. These results provide an experimental basis for the observed genetic association with chronic inflammatory lung diseases, and also suggest the potential therapeutic utility of this antagonistic variant of IL-17F. Given that asthma and COPD are complex diseases involving a number of genetic and environmental factors, the genetic impact of IL-17F H161R with regard to the development of chronic airway inflammation likely varies among individuals with different genetic backgrounds and environmental exposures. [source] Using molecular and quantitative variation for assessing genetic impacts on Nucella lapillus populations after local extinction and recolonizationINTEGRATIVE ZOOLOGY (ELECTRONIC), Issue 2 2006Isabelle Colson Abstract The dogwhelk Nucella lapillus is a predatory marine gastropod living on rocky shores in the North Atlantic. As with many other gastropod species, Nucella was affected by tributyltin (TBT) pollution during the 1970s and 1980s, and local populations underwent extinction. After a partial ban on TBT in the UK in 1987, vacant sites have been recolonized. Levels of genetic diversity and quantitative genetic variation in shell form were compared between recolonized sites and sites that showed continuous population at three localities across the British Isles. Overall, estimates of genetic diversity were only slightly lower in recolonized populations, suggesting that populations have recovered from previous impacts due to the relatively high levels of migration from non-impacted sites. Molecular and quantitative analyses are broadly concordant and a positive correlation was observed (although not statistically significant) between molecular and quantitative estimates of genetic diversity, indicating the potential usefulness of quantitative methods to complement molecular population genetics analyses. [source] Development of polymorphic microsatellite loci in Nothapodytes nimmoniana, a medicinally important tree from the Western Ghats, IndiaMOLECULAR ECOLOGY RESOURCES, Issue 1 2009B. T. RAMESHA Abstract Nothapodytes nimmoniana is a medicinally important tree species that occur in the Western Ghats, a megadiversity hotspot in southern India. Inner stem bark of the tree contains an important anti-cancer alkaloid, camptothecin for which the natural population of the tree is heavily harvested. In this paper, we report the isolation and characterization of eight polymorphic microsatellite loci using enrichment hybridization protocol. Analysis of 36 individuals representing two populations revealed three to 12 alleles per locus. Observed heterozygosity ranged from 0.21 to 0.94 for the two populations. None of the loci tested showed linkage disequilibrium. These markers are invaluable for evaluating the genetic structure and assessing the genetic impacts of harvesting of N. nimmoniana in the Western Ghats to formulate strategies for conservation of the species. [source] | |||||||||||||