[Apolipoprotein E (apoE) is a glycoprotein participating in the lipid transport and metabolism and in the neuronal regeneration processes. The gene of apo (APOE) is localized on the long arm of chromosome 19. The genetic polymorphism of APOE is manifested in three common alleles. The frequencies of these alleles, APOE2, APOE3, APOE4 are different in various human populations depending on their geographical origin. The APOE alleles have been considered to be responsible for the inter-individual variations of the serum cholesterol level. Besides its function in lipid transport, there are other relatively unknown but proven functions of apoE in the development of the nervous system and in peripheral nerve regeneration after injury. ApoE is considered as an important etiophathogenetic factor of atherosclerosis, familial hypercholesterolaemia and hyperlipoproteinaemia type III. The results of biochemical, molecular biological, population genetic and neuropathological examinations of the last three years have provided evidence that APOE4 alleles could be important risk factors of Alzheimer's dementia (AD). Recent findings regarding the relationship of apoE and AD are reviewed by the authors in connection with other aetiopathogenetic factors such as development of senile plaques, mutations of amyloid precursor protein gene, familial and sporadic forms of AD. These factors are discussed in relation to the therapeutic implications and dilemmas of genetic testing of APOE in AD.]

[In this review we summarise the current results of the genomic investigation of allergic diseases. From the genetic point of view allergy is multifactorial, which means that the susceptibility to the disease is determined by the effect of one or more genes or the interactions between multiple genes and involves important nongenetic factors such as the environment for their expression. Among allergic diseases the genomic background of asthma was studied most thoroughly. Until now, using hundreds of DNA markers, located across all of the human chromosomes, 16 genome-wide screens for susceptibility genes for asthma or asthma related intermediate phenotypes in 12 different populations have been published and 20 chromosomal regions have been highlighted for further analysis. In genetic association studies more than 500 genes were identified as candidate genes for asthma. In this review, we selected those results which were consistently reported by several independent studies or appeared particularly important or interesting. According to the results of the human genome programs and association studies we discuss the possible roles of candidate genes found in these loci in the pathomechanism of allergy and atopy.]

[Bioinformatics is one of the most important element of genomic research revolutionising biomedical science. This review describes the phenomena of genomic variance and comparative genomics. Briefly, the review summarises the identification procedure of new genes and gene expression patterns highly important in diagnostics. Bioinformatic procedures make possible the rapid detection of pathogens and have principal role in molecular drug design technologies.]

[The lipoprotein metabolism, having crucial role in atherogenesis is regulated by apolipo proteins, lipoprotein receptors and lipidtrans ferase enzymes. The genetic polymorphism of these proteins has been reported to be associated with lipid disorders. Beneath the rare forms (familial hypercholesterolemia, familial defective apo B syndrome) the most important monogenetic dyslipoproteinemia seems to be related to the apolipoprotein E polymorphism. The mean serum cholesterol concentration is influenced by the different apo E phenoytpes (E4 with high, E2 with low cholesterol level). In Hungary, the allele-frequencies (22 0,06, 22 0,80, 34 0,12) and the effect of apo E alleles on cholesterol concentration are very similar to the results found in other populations. Apo E polymorphism shows association with 1. hyperlipoproteinemia type III (E 2/2); 2. dyslipoproteinemia in familial hypercholeste rolemia (E2); 3. premature coronary heart disease (E4); 4. hypercholesterolemia in some populaton (E4); 5. insulin dependent diabetes mellitus in the Hungarian population (E2); 6. the rate of intestinal cholesterol absorption in some population (E4 with higher capacity). In such conditions the determination of apo E phenotype or genotype is very important to reveal the risks of the atherosclerosis and to asses the optimal hypolipidemic therapy.]

[The investigation of schizophrenia’s aetiology and pathomechanism is of high importance in neurosciences. In the recent decades, analyzing event-related potentials have proven to be useful to reveal the neuropsychological dysfunctions in schizophrenia. Even the very early stages of auditory stimulus processing are impaired in this disorder; this might contribute to the experience of auditory hallucinations. The present review summarizes the recent literature on the relationship between auditory hallucinations and event-related potentials. Due to the dysfunction of early auditory sensory processing, patients with schizophrenia are not able to locate the source of stimuli and to allocate their attention appropriately. These deficits might lead to auditory hallucinations and problems with daily functioning. Studies involving high risk groups may provide tools for screening and early interventions; thus improving the prognosis of schizophrenia. ]