RESUMO
Natural gas seepage pockmarks are found off- and onshore in the Öxarfjörður graben, Iceland. The bacterial communities of two onshore seepage sites were analysed by 16S rRNA gene amplicon sequencing; the geochemical characteristics, hydrocarbon content, and the carbon isotope composition of the sites were also determined. While one site was found to be characterised by biogenic origin of methane gas, with a carbon isotope ratio (δ13C ()) of -63.2, high contents of organic matter and complex hydrocarbons, the other site showed a mixed origin of the methane gas (δ13C () = -26.6) with geothermal characteristics and lower organic matter content. While both sites harboured Proteobacteria as the most abundant bacterial phyla, the Deltaproteobacteria were more abundant at the geothermal site and the Alphaproteobacteria at the biogenic site. The Dehalococcoidia class of phylum Chloroflexi was abundant at the geothermal site while the Anaerolineae class was more abundant at the biogenic site. Bacterial strains from the seepage pockmarks were isolated on a variety of selective media targeting bacteria with bioremediation potential. A total of 106 strains were isolated and characterised, including representatives from the phyla Proteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria. This article describes the first microbial study on gas seepage pockmarks in Iceland.
Assuntos
Carvão Mineral/microbiologia , Sedimentos Geológicos/microbiologia , Microbiota , Gás Natural/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Bioprospecção , Carvão Mineral/análise , Sedimentos Geológicos/química , Hidrocarbonetos/análise , Islândia , Metano/análise , Microbiota/genética , Gás Natural/análise , RNA Ribossômico 16S/genéticaRESUMO
We performed a genome-wide association study on 1,292 individuals with abdominal aortic aneurysms (AAAs) and 30,503 controls from Iceland and The Netherlands, with a follow-up of top markers in up to 3,267 individuals with AAAs and 7,451 controls. The A allele of rs7025486 on 9q33 was found to associate with AAA, with an odds ratio (OR) of 1.21 and P = 4.6 x 10(-10). In tests for association with other vascular diseases, we found that rs7025486[A] is associated with early onset myocardial infarction (OR = 1.18, P = 3.1 x 10(-5)), peripheral arterial disease (OR = 1.14, P = 3.9 x 10(-5)) and pulmonary embolism (OR = 1.20, P = 0.00030), but not with intracranial aneurysm or ischemic stroke. No association was observed between rs7025486[A] and common risk factors for arterial and venous diseases-that is, smoking, lipid levels, obesity, type 2 diabetes and hypertension. Rs7025486 is located within DAB2IP, which encodes an inhibitor of cell growth and survival.
Assuntos
Aneurisma da Aorta Abdominal/genética , Alelos , Aneurisma da Aorta Abdominal/complicações , Aneurisma da Aorta Abdominal/mortalidade , Sequência de Bases , Suscetibilidade a Doenças/complicações , Estudo de Associação Genômica Ampla , Humanos , Hipertensão/complicações , Hipertensão/genética , Islândia , Infarto do Miocárdio/complicações , Infarto do Miocárdio/genética , Países Baixos , Razão de Chances , Fatores de Risco , Proteínas Ativadoras de ras GTPaseRESUMO
Smoking is a leading cause of preventable death, causing about 5 million premature deaths worldwide each year. Evidence for genetic influence on smoking behaviour and nicotine dependence (ND) has prompted a search for susceptibility genes. Furthermore, assessing the impact of sequence variants on smoking-related diseases is important to public health. Smoking is the major risk factor for lung cancer (LC) and is one of the main risk factors for peripheral arterial disease (PAD). Here we identify a common variant in the nicotinic acetylcholine receptor gene cluster on chromosome 15q24 with an effect on smoking quantity, ND and the risk of two smoking-related diseases in populations of European descent. The variant has an effect on the number of cigarettes smoked per day in our sample of smokers. The same variant was associated with ND in a previous genome-wide association study that used low-quantity smokers as controls, and with a similar approach we observe a highly significant association with ND. A comparison of cases of LC and PAD with population controls each showed that the variant confers risk of LC and PAD. The findings provide a case study of a gene-environment interaction, highlighting the role of nicotine addiction in the pathology of other serious diseases.
Assuntos
Cromossomos Humanos Par 15/genética , Predisposição Genética para Doença/genética , Neoplasias Pulmonares/genética , Doenças Vasculares Periféricas/genética , Polimorfismo de Nucleotídeo Único/genética , Receptores Nicotínicos/genética , Tabagismo/genética , Europa (Continente) , Feminino , Genótipo , Humanos , Masculino , Família Multigênica/genética , Nova Zelândia , Razão de Chances , Fumar/efeitos adversos , Fumar/genéticaRESUMO
The global endemic of cardiovascular diseases calls for improved risk assessment and treatment. Here, we describe an association between myocardial infarction (MI) and a common sequence variant on chromosome 9p21. This study included a total of 4587 cases and 12,767 controls. The identified variant, adjacent to the tumor suppressor genes CDKN2A and CDKN2B, was associated with the disease with high significance. Approximately 21% of individuals in the population are homozygous for this variant, and their estimated risk of suffering myocardial infarction is 1.64 times as great as that of noncarriers. The corresponding risk is 2.02 times as great for early-onset cases. The population attributable risk is 21% for MI in general and 31% for early-onset cases.
Assuntos
Cromossomos Humanos Par 9/genética , Predisposição Genética para Doença , Variação Genética , Infarto do Miocárdio/genética , Polimorfismo de Nucleotídeo Único , Idade de Início , Idoso , Estudos de Casos e Controles , Mapeamento Cromossômico , Doença da Artéria Coronariana/genética , Feminino , Genes p16 , Genótipo , Haplótipos , Heterozigoto , Homozigoto , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
Age-related macular degeneration (AMD) is the main reason for blindness today in the western hemisphere. According to Björn Olafsson, who was the first ophthalmologist in Iceland a century ago, this disease was not found in Iceland. In the blindness-registry of 1950 6% blindness was due to this disease. Today, AMD is responsible for 54% of legal blindness in Iceland. The incidence of the disease increases with age. Heredity and environmental factors are thought to influence its etiology. Indirect methods, including twin studies and increased frequency of this disease in some families, have demonstrated that hereditary factors may be important. This has been confirmed recently by demonstrating that genes on chromosome 1 and chromosome10 play a role. This disease is classified as early stage, with drusen and pigmentary changes and insignificant visual loss. Treatment options for this stage are limited. The use of vitamin E and C and Zinc has, however, been shown to delay its progress. The second and end stage involves visual loss, either as a dry form with pigment epithelial atrophy or wet form, with new vessel formation. Treatment options for the dry form are limited. The second form is more common in Iceland than in other countries. Treatment options for the wet form have increased. Localised laser and drug treatment to neovascular membranes, either alone or as a combination treatment with drugs that have anti-proliferate effect on new vessels (anti-VEGF) are increasingly used. New treatment methods are also used in assisting those that are already visually handicapped. The use of computers is increasing as are the patients' computer skills. As the number of the elderly increases, AMD will be an increasing health problem in Iceland as in other Western countries. It is therefore important to improve the treatment options and the service and counselling of patients.