Proč se nekříží kočka se psem? Proč se sice může zkřížit kůň s oslem, ale jejich potomci - mulové či mezci - jsou neplodní? Z jakého důvodu jsou někdy strilní i kříženci dvou blízce příbuzných poddruhů, třeba myší, a souvisí to nějak se vznikem nových živočišných druhů? Jeden z nejdůležitějších článků tété záhady odhalil Jiří Forejt z Ústavu molekulární genetiky Akademie věd ČR, kterýá identifikoval první gen u savců zodpovědný za samčí neplodnost mezidruhových kříženců, přečetl ho a ukázal, jak je regulován. and Jana Olivová, Stanislava Kyselová.
Hypertension is a major health problem throughout the world because of its high prevalence and its association with increased risk of cardiovascular disease. Two independent studies discovered a locus conferring susceptibility to essential hypertension on chromosome 2, in the 2p25 region, but the causative gene remains unknown. Grainyhead-like 1 (GRHL1) is one of the genes located in this region. Our experiments determined that the Grhl1-null mice, when fed standard diet, have the same blood pressure as their wild type littermate controls. However, we discovered that blood pressure of these mice increases following high sodium diet and decreases when they are fed low sodium diet, and similar effect s were not observed in the control wild type littermates. This suggests that the Grhl1-null mice are sensitive to the development of salt-sensitive hypertension. Thus it is possible that the GRHL1 gene is involved in the regulation of blood pressure, and it may be the causative gene for the locus of susceptibility to essential hypertension in the 2p25 region., A. Walkowska, M. Pawlak, S. M. Jane, E. Kompanowska-Jezierska, T. Wilanowski., and Obsahuje bibliografii
The apolipoprotein A-V (apo A-V) plays an important role in regulation of triglyceride (TG) concentration in serum. To better understand how apo A-V affects triglyceridemia and glucoregulation, the lipoprotein lipase (LPL) activity was determined using intravenous fat tolerance test (IVFTT) and oral glucose tolerance test (oGTT) was performed in carriers of apolipoprotein A-V gene ( APOAV) variants known to be associated with increased triglyceridemia. Twelve carriers of 19W variant, 16 carriers of -1131C variant, 1 combined heterozygote and 16 control subjects homozygous for wild type variants (19S/-1131T) were selected from a population sample and matched with respect to body mass index and age. The APOAV variants carriers had increased TG, very low density lipoprotein-TG, and apo B concentrations (p < 0.05). The LPL activity evaluated as k2 rate constant for clearance of Intralipid® was 14 % lower in APOAV variants carriers. The depression of nonesterified fatty acids (NEFA) concentration after glucose load was delayed in APOAV variants carriers in spite of the same insulinemia and glycemia. Our results suggest that variants of APOAV combined with increased triglyceridemia are associated with lower LPL activity in vivo and with disturbances of regulation of NEFA concentration after glucose load., J. Kovář, V. Adámková., and Obsahuje bibliografii a bibliografické odkazy
The European Molecular Biology Organization organized a meeting in Prague October 1-3. At this symposium several topics were discussed: biology and genetics of mitochondria in relation to cancer; the role of mitochondria-targeting compounds in cancer suppression (including BH3 mimetics); mitochondria as transmitters of death receptor-induced apoptosis; regulation of apoptosis and the interplay of mitochondria with other organelles p53 and mitochondria in apoptosis regulation; and the role of mitochondria in targeting cancer stem cells. and Jiří Neužil, Ladislav Anděra a Alois Kozubík.
The long QT syndrome (LQTS) is a monogenic disorder characterized by prolongation of the QT interval on electrocardiogram and syncope or sudden death caused by polymorphic ventricular tachycardia (torsades de pointes). In general, mutations in cardiac ion channel genes (KCNQ1, KCNH2, SCN5A, KCNE1, KCNE2) have been identified as a cause for LQTS. About 50-60 % of LQTS patients have an identifiable LQTS causing mutation in one of mentioned genes. In a group of 12 LQTS patients with no identified mutations in these genes we have tested a hypothesis that other candidate genes could be involved in LQTS pathophysiology. SCN1B and KCND3 genes encode ion channel proteins, ANK2 gene encodes cytoskeletal protein interacting with ion channels. To screen coding regions of genes SCN1B, KCND3, and 10 exons of ANK2 following methods were used: PCR, SSCP, and DNA sequencing. Five polymorphisms were found in screened candid ate genes, 2 polymorphisms in KCND3 and 3 in SCN1B. None of found polymorphisms has coding effect nor is located close to splice sites or has any similarity to known splicing enhancer motifs. Polymorphism G246T in SCN1B is a novel one. No mutation directly causing LQTS was found. Molecular mechanism of LQTS genesis in these patients remains unclear., M. Raudenská, A. Bittnerová, T. Novotný, A. Floriánová, K. Chroust, R. Gaillyová, B. Semrád, J. Kadlecová, M. Šišáková, O. Toman, J. Špinar., and Obsahuje bibliografii a bibliografické odkazy
Moravské zemské muzeum v Brně bylo vždy nositelem Mendelova badatelského odkazu, a to prostřednictvím bývalé vědecké akademie pro Moravu a Slezsko, tzv. Hospodářské společnosti (Ackerbaugesellschaft) a jejího Přírodozpytného spolku (Naturforschender Verein). Jako druhou největší a nejstarší muzejní instituci jej založila Moravskoslezská hospodářská společnost, jejímž členem se roku 1854 stal i Gregor Johann Mendel (1822-1884). Zapojil se nejen do organizační práce ve většině sekcí společnosti, ale také do výzkumu. Byl tedy v přímém kontaktu s počátečním vývojem současného Moravského zemského muzea. and Jiří Sekerák, Eva Matalová, Michal V. Šimůnek.
Functional C(-260)→T polymorphism in the promoter of the CD14 gene has been reported to be associated with coronary heart disease (CHD). The functional role of the polymorphism, however, is still a matter of debate, since several studies have not proved its effect on clinical outcomes associated with atherosclerosis. Cardiovascular-related morbidity and mortality was assessed in a post-hoc approach four years after baseline characterization of patients (male/female n = 36/32) with angiographically proven coronary heart disease. CD14 C(-260)→T promoter genotype was determined at baseline. Seventeen out of 20 CHD patients with non-lethal cardiovascular events carried at least one T-allele. CD14 T-260 allele carriers have a 3.59-fold (95 % confidence interval: 1.11-6.75) increased risk for non-lethal cardiovascular events (Kaplan-Meier plot: log rank test p = 0. 029). All patients with lethal outcomes (n = 6) were also T-allele carriers. Multivariate logistic regression analysis among CHD patients including age, established risk factors and the C(-260)→T polymorphism as covariates and non-lethal events as a dependent variable confirmed the independent prospective effect of the T-allele on cardiovascular outcomes in this subset. Further evidence is provided for the role of CD14 C(-260)→T promoter polymorphism as a genetic susceptibility marker of atherosclerosis in patients with an advanced clinical course of the disease. Due to the small sample size and post-hoc character of the study large-scale prospective studies that monitor patients with proven CHD are needed to confirm these findings., M. Porsch-Öucürümez, J.Hucke, S. Westphal, J. A. Hubáček, G. Schmitz, C. Luley., and Obsahuje bibliografii a bibliografické odkazy
It is said that dog genome has 2 385 199138 base couples and 20 439 genes which is less than man. It has been described as having about 2,5 million polymorphisms which give us knowledge about more than 400 various kinds of dogs. and Jaromír Dostál.