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Motor neuron disease (MND) results in the selective degeneration of motor neurons in the cerebral cortex, brain stem and spinal cord. The most common form of MND is amyotrophic lateral sclerosis (ALS). MND is complex and many genetic systems may be involved in the pathogenesis of this disease. Pathological and animal studies implicate neurofilament involvement in MND. The heavy subunit (NEFH) tail domain contains a repeated motif. In humans, there are two common variants: the 45 motif repeats long allele (L) and 44 motif repeats short allele (S). Previous studies have shown that the NEFH tail may be involved in the pathogenesis of MND. To investigate whether the L/S genotypes of the NEFH gene are associated with MND, we studied the frequency of L and S alleles in sporadic MND patients and a control population from Moscow. We observed a difference in SS genotype frequency between the control population and sporadic MND patients from Moscow. It was established that the SS genotype is sufficiently higher in sporadic MND patients. Moreover, we determined that patients with the SS genotype have the highest value of loss of the total clinical score. In summary, we conclude that the NEFH gene is involved in the pathogenesis of sporadic MND. The SS genotype represents a risk factor for the development and progression of sporadic MND in the Moscow population.

Autosomal recessive juvenile parkinsonism (AR-JP) is a form of hereditary parkinsonism characterized by variable clinical presentations and caused by mutations in a novel gene, parkin, on chromosome 6q25.2-27. Until now, no Russian cases of parkin-associated AR-JP have been reported on. We recruited 16 patients from 11 Russian families with dopa-responsive movement disorders according to the following criteria: 1) family history compatible with autosomal recessive inheritance; 2) onset of symptoms at/=30 years of age; and 3) the lack of mutations in the GTP cyclohydrolase I gene (in sporadic cases). Mutation screening of the parkin gene was carried out by a semiquantitative PCR assay and direct sequencing of the coding region. Six different parkin mutations (both deletions and point mutations) were identified in the index cases from four families, including a novel point mutation in the donor splice site (IVS1+1G--A). The majority of our parkin-associated cases were characterized by early-onset dopa-responsive parkinsonism with benign course and slow progression (5 patients from two families have been followed for as long as 18-36 years), and 1 patient had a phenotype of dopa-responsive dystonia. This first description of Russian patients with AR-JP and molecularly proven parkin mutations confirms the widespread occurrence of this polymorphic hereditary extrapyramidal disorder.

Apolipoprotein B 3' (3' ApoB) minisatellite polymorphism was studied in healthy unrelated individuals from the Russian Federation and the Republic of Belarus, in 10 populations from five ethnic groups: Russians, Byelorussians, Adygeis, Kalmyks and Yakuts. The analysis was carried out using PCR and electrophoresis followed by silver staining. Overall, 25 alleles of the 3' ApoB minisatellite, ranging from 25 to 55 repeats, were detected. Heterozygosity indices were high and varied from 0.73 to 0.84. The distributions of alleles of this minisatellite in the Caucasoid populations (Russians, Byelorussians and Adygeis) had a bimodal character, whereas that for Mongoloid populations (Kalmyks and Yakuts) had a unimodal distribution. Nei's genetic distances between the populations studied and some reference populations of Europe and Asia were estimated. Despite their allele distribution homogeneity, different East Slavonic ethnic groups were clearly resolved by multidimensional analyses. The East Slavonic and Adygei populations revealed a high similarity with European Caucasoids. The Mongoloid populations (Kalmyks and Yakuts) were considerably different from those of the European Caucasoid populations, but were similar to other Asian Mongoloid populations. The results demonstrate the variability of 3' ApoB minisatellite polymorphism not only in distant populations but also, to a certain extent, in genetically relative ones.

A normal polymorphism at three triplet repeat loci (myotonic dystrophy (DM), dentatorubral-pallidoluysian atrophy (DRPLA) and spinocerebellar ataxia type 1 (SCA1)) were examined in healthy unrelated individuals from the Siberian Yakut (Mongoloid) population, the Adygei (Caucasian) population and nine East European populations: populations from Russia (Holmogory, Oshevensk, Kursk, Novgorod, Udmurts, Bashkir), two Ukrainian populations (Lviv and Alchevsk) and one Belarussian. The distribution of alleles for DRPLA and SCA1 were similar for all East-European populations. For the DM locus, East European populations had typical allele distribution profiles with two modes, (CTG)5 and (CTG)11–14, but some differences were found for the Bashkir population where alleles containing 11–14 CTG repeats had relatively higher frequency. The Yakut population had different allele spectra for all types of repeats studied. Higher heterozygosity levels and insignificant differences between expected and observed heterozygosity were found for all tested loci. The latter led us to suggest that the trinucleotide repeat loci analysed are not influenced by selection factors and could be useful for genetic relationship investigations in different populations.

A genetic perspective of human history in Europe was derived from 22 binary markers of the nonrecombining Y chromosome (NRY). Ten lineages account for >95% of the 1007 European Y chromosomes studied. Geographic distribution and age estimates of alleles are compatible with two Paleolithic and one Neolithic migratory episode that have contributed to the modern European gene pool. A significant correlation between the NRY haplotype data and principal components based on 95 protein markers was observed, indicating the effectiveness of NRY binary polymorphisms in the characterization of human population composition and history.

A highly polymorphic microsatellite (CA)n-marker (CAct685) previously isolated from human chromosome 19 cosmid library was localized near GPI in 19q13.1. For the fine localization of this marker, the hybridization with chromosome 19-specific cosmid libraries assembled in contigs was used. Polymorphism analysis of the marker in 12 populations of Russia and neighboring countries showed 14 alleles containing from 16 to 30 repeat units. Populations belonging to Indo-European, Uralic and Altaic linguistic families demonstrated a great similarity in allele frequency profiles. Differences between these populations were lower for CAct685 than for classical markers. Allele distribution of CAct685 in a Chukchi population belonging to the Chukchi-Kamchatkan linguistic family differs from those in all other populations, that may be typical for Mongoloid population or reflect an ethnic history of Chukchi as a small population. Thus use of the CAct685 marker seems to be effective for analysis of distant peoples.

DNA fingerprinting techniques have been used in population genetic studies on many different kinds of organisms. Here, we present new applications for multilocus DNA fingerprint probes in population studies and demonstrate the applicability of DNA fingerprinting to human population genetics, using M13 phage DNA as a probe. The new approach, which is based on a factor method of numerical coding of non-quantitative data (factor correspondence analysis-FCA), shows good agreement between population position, as indicated by the three principal factors, and ethnogenetic proximity.

Background Extensive genome-wide analyses of many human populations, using microarrays containing hundreds of thousands of single-nucleotide polymorphisms, have provided us with abundant information about global genomic diversity. However, these data can also be used to analyze local variability in individual genomic regions. In this study, we analyzed the variability in two genomic regions carrying the genes of the GSTA and GSTM subfamilies, located on different chromosomes. Results Analysis of the polymorphisms in GSTA and GSTM gene clusters showed similarities in their allelic and haplotype diversities. These patterns were similar in three Russian populations and the CEU population of European origin. There were statistically significant differences in all the haploblocks of both the GSTM and GSTA regions when the Russian populations were compared with populations from China and Japan. Most haploblocks also differed between the Russians and Nigerians from Yoruba, but, some of them had similar allelic frequencies. Special attention was paid to SNP rs4986947 from the intron of the GSTA4 gene, which is represented in apes by an A nucleotide. In the Asian and African samples, it was represented only by a G allele, and both allelic variants (G/A) occurred in the Russian and European populations. Conclusions The results obtained suggest the presence of common features in the evolutionary histories of the GSTA and GSTM gene regions, and that African subpopulations were involved differently in the formation of the European and Asian human lineages.

An oligonucleotide (m 5 C-am 2 A-m 5 C) 5 containing 2′-amino-deoxyadenosine (am 2 A) and 5-methyldeoxycytidine (m 5 C) residues has been synthesized and compared with unsubstituted pentadecadeoxyribonucleotide (CAC) 5 as a hybridization probe for DNA fingerprinting. It was shown that considerably higher sensitivity can be achieved with the modified analog.

To obtain new polymorphic probes, a human genomic library was screened by P-labelled (CAC)s, (TCC)5, (GACA)4 and M13 minisatellite "core" sequence 5'-GAGGGTGGCGGCGCT-3'. Several clones simultaneously hybridizing to different probes were isolated and sequenced. One of them was found to contain (CAC)68repeat and two new tandemly organized repeats, one of which was designated as minisatellite K25 (EMBL accession numbers follow: x81325 Homo sapiens H12A gene, x81326 Homo sapiens H12B gene). K25 is composed of an array of 16to 25-bp tandem repeats with a copy number equal to 24. It has partial homology to G-rich consensus sequences previously defined in repeated units of some minisatellites and to the sequence chi. The 16-bp core sequence of K25 (5'-GATGGAGGGATGGGGG-3') was used to obtain synthetic tandemly repeated sequence (K25 STRS). When used as a probe for BspRl digests of human DNA, the K25 STRS revealed hypervariable alleles demonstrating individual-like fingerprints different from those obtained with M13 phage DNA (Fig. 1). Acknowledgments: This work was partly supported by the grants of Russian Fund of Fundamental Researches, Russian State Program "Biodiversity" and Russian State Programme "Frontier in Genetics."

The Byelorussian populations are from three regions of the Republic of Belarus (Grodno, Bobruisk, and Mjadel areas); the Russians are from the Kholmogory town of the Russian Federation (Arkhangelsk district); and the Ukrainian populations are from the Kiev and L’vov areas of Ukraine. The Mordva-Moksha (StaroShaiginsk and Romodanovsk areas of Mordva Republic), the Bashkirs (Ilishevsky, Abzelilovsky, Sterlibashevsky, Arkhangelsky, and Beloretsky districts of Bashkir Republic), the Komi-Zyrjan (Sysolsky district of Komi Republic), the Tartar (Almetyevsk town of Tartar Republic), and the Mari (Zvenigovsk area of Mari Republic) populations present distinct ethnic groups of the region between the Volga River and the Ural Mountains in Russia. Eastern Slavonic populations (Russians, Byelorussians, Ukrainians) are Caucasoids; other populations were considered as admixture populations with different levels of a Mongoloid component. Blood samples were collected in EDTA vacutainer tubes from healthy unrelated volunteers belonging to a native ethnic group of the regions studied. DNA was isolated by phenol-chloroform ex

Autosomal recessive limb gird muscular dystrophy (LGMD2) is a clinically and genetically heterogeneous group of diseases that are characterized by progressive atrophy and weakness of the proximal limb muscles. At least eight genetic loci leading to LGMD2 are recognized. The proportion of particular gene involved in producing different forms of LGMD2 shows a marked geographical variation. We studied 19 LGMD2 patients from Russia (15 families) and found calpain 3 (CAPN3) gene mutations in most of the patients studied. Sequence analysis of the fourth exons revealed two sibs – heterozygous compound for a 15-bp deletion (nt598-612) and 550 adenine deletion, and two sibs homozygous for a 550delA. We developed assay based on allele specific amplification (ASA) for rapid screening of the 550delA. The ASA assay of the LGMD2 patients under study showed that 7 patients from 6 families were homozygous for 550delA and 7 patients from 4 families were heterozygous for 550delA. A linkage analysis employing four microsatellites flanking the LGMD2A locus was performed. We found complete haplotype identity in most cases what favors the possibility of a common founder. Heterozygous carriers of 550delA were found in general population. The crude estimate of the mutation frequency is 1/150. Hum Mutat 15:295, 2000. © 2000 Wiley-Liss, Inc.

Hereditary torsion dystonia represent a clinically and genetically heterogeneous group of movement disorders. The most severe and frequent form of hereditary torsion dystonia is early-onset generalized dystonia, DYT1. The DYT1 gene (Ozelius et al., 1997) encodes an ATP-binding protein torsin A. A unique 3-bp deletion (GAG) was found in the heterozygous state in almost all patients with early-onset dystonia from different populations. We observed 39 patients with early-onset generalized torsion dystonia belonging to 22 families from Russia. Seven families were of Ashkenazi Jewish (AJ) ethnic background, and other patients originated from the Slavonic population of Russia. The GAG deletion was identified in 24 affected persons from 15 families (68.2% of the families studied). In all the 7 families of AJ origin the disease was found to be caused by the deletion. In Slavs, the deletion was identified in 8 of 15 families (53%). In two deletion-positive families we observed the co-occurrence of typical early-onset generalized dystonia and atypical phenotypes-either isolated postural hand tremor or stutter. Hum Mutat 14:269, 1999. © 1999 Wiley-Liss, Inc.

Objective To search for mutations in the GTP cyclohydrolase I (GCH-I) gene in a set of Russian families with dopa-responsive dystonia (DRD). Design Six large families with 54 affected family members and 2 patients with sporadic DRD were examined. Mutation screening was performed using single-strand conformation polymorphism analysis followed by direct sequencing of the presumably mutated exons; in patients whose results showed a normal pattern on single-strand conformation polymorphism analysis, the entire coding region of theGCH-Igene was sequenced. Results Three new heterozygote point mutations located within exons 1, 2, and 4 of theGCH-Igene were identified in 3 families with autosomal-dominant inheritance. All these mutations are predicted to cause amino acid changes in the highly conserved regions of the gene. In patients from 3 other families and in both patients with sporadic DRD, no alterations in the translated portion of theGCH-Igene were observed. Conclusions Mutations in the coding region of theGCH-Igene account for a significant fraction (up to half) of the patients with a typical clinical picture of DRD. None of the mutations in theGCH-Igene described so far were detected more than once, which precludes the possibility of creating simple DNA testing procedures for routine clinical practice.

It has been shown previously that after self-annealing of the nuclear precursor of messenger RNA (premRNA) at high values of Cot about 20% of the material becomes resistant to ribonuclease digestion [ 1 ] . This was explained by the existence of self-complementary regions in the molecules of pre-mRNA and by the ability of these sequences to form doublestranded complexes after annealing. In this paper we report on the isolation and the most important properties of this fraction of RNA (self-complementary RNA or scRNA). Its possible origin is discussed.

Hypervariable polymorphic patterns were detected with M13 phage DNA as a probe in genomic DNA of organisms belonging to different taxonomic groups including animals (vertebrates and invertebrates), plants and microorganisms. Individual-specific restriction pattern analysis (DNA fingerprinting) with this probe proved to be useful for individual identification, analysis of somatic stability and paternity testing in man. The nuclear type of inheritance indicates that the hypervariable DNA regions in question are located in the chromosomes, not in the mitochondrial DNA. The data obtained also demonstrate a potential range of M13 DNA applications as a probe for DNA fingerprinting of animals, plants and microorganisms, particularly for the determination of inbred lines, identification of bacterial strains and establishing stock, variety and strain distinctions.

About 25% of the double-stranded sequences isolated from pre-mRNA are able to hybridize, after melting, with either mRNA or non-melted pre-mRNA. The retention of one branch of pre-mRNA hairpin in mRNA was suggested. It was also found that in addition to the hairpin-like structures comprising about 3% of the total sequences another 15% of the pre-mRNA sequences can form double-stranded structures upon annealing over a broad interval of Cot values.

Studies of β-thaiassemia, a hereditary blood disease associated with deficient expression of the β-globin gene, have revealed a variety of mutations underlying this condition. So far 40 such mutations have been revealed by various molecular genetic techniques (Kan, 1986). They include point substitutions, deletions and insertions, which affect different stages of the functioning of the β-globin gene. β-thalassemia is believed to be caused by different sets of mutations in different ethnic groups. It is important to take this into account when developing diagnostic and prevention approaches for a particular region (Antonarakis et al., 1985).

The study of genome activity in highly differentiated cells provides basic data on the selective use of genetic information in a concrete situation. It is particularly interesting to analyze the work of genes in the nerve tissue, which is the most complexly organized system of highly differentiated cells. Genetic engineering makes it possible to clone genes functioning in a particular kind of cells using appropriate mRNA or cDNA copies as starting material. It is important to analyze not only active unique genes but also the repetitive sequences working in differentiated cells which may be involved in the regulation of gene activity.

Two clones have been selected from a human fibroblast cDNA bank. By DNA sequencing the clones were shown to contain Alu elements located near the ends of the cDNA inserts. DNA of the clones was used for Northern blot hybridization analysis of a number of poly(A)-containing RNAs from normal human tissues (brain, stomach, uterus, spleen, fibroblasts) and tumors (neurinoma, glioma, neuroblastoma, liposarcoma, adrenal cortex adenocarcinoma). All RNA samples reveal a heterodisperse distribution of Alu transcripts with discrete bands in the region of 7-12 S RNA. The majority of these small poly(A)+ Alu+ RNAs contain Alu sequences only in one (canonical) orientation with functional signals including the split promoter for RNA polymerase III.

Parkinson’s disease (PD) is a multifactorial neurodegenerative disease whose pathogenesis involves a number of genes and environmental factors. The FGF20 gene encoding the fibroblast growth factor and paying an important role neuron proliferation and survival is one of candidate genes of PD. There is evidence that this gene is also involved in the control of α-synuclein (SNCA) gene expression. The rs12720208 single-nucleotide polymorphism (SNP) in the FGF20 gene has been found to be associated with PD; it has been located to the 3′-UTR binding site for microRNA-433, which is involved in the control of FGF20 expression. Therefore, the frequency distribution of rs12720208 genotypes in the FGF20 gene has been analyzed in a sample of patients with sporadic PD and a control sample of the Russian population. The results have not shown any effect of rs12720208 in the FGF20 gene on the risk of PD in patients residing in Russia (OR = 0.95, the 95% confidence interval (CI) is 0.55–1.63, p = 0.9).

Background GSTM1 gene deletion is one of the most known copy number polymorphisms in human genome. It is most likely caused by homologous recombination between the repeats flanking the gene. However, taking into account that the deletion has no crucial effects on human well-being, and the ability of other GSTMs to compensate for the lack of GSTM1, a role for additional factors affecting GSTM1 deletion can be proposed. Our goal was to explore the relationships between GSTM1 deletion polymorphism and single nucleotide polymorphisms (SNPs) in the region of the GSTM cluster that includes GSTM2, GSTM3, GSTM4, and GSTM5 in addition to GSTM1. Results Real-time polymerase chain reaction was used to quantify the number of GSTM1 copies. Fourteen SNPs from the region were tested and their allelic patterns were compared in groups of Russian individuals subdivided according to their GSTM1 deletion genotypes. Linkage disequilibrium-based haplotype analysis showed substantial differences of haplotype frequencies between the groups, especially between individuals with homozygous GSTM1 −/− and +/+ genotypes. Exploration of the results of phasing of GSTM1 and SNP genotypes revealed unequal segregation of GSTM1 + and − alleles at different haplotypes. Conclusions The observed differences in haplotype patterns suggest the potential role of genetic context in GSTM1 deletion frequency (appearance) and in the determination of the deletion-related effects.

Background One of the causes of Parkinson's disease is mutations in the PARK2 gene. Deletions and duplications of single exons or exon groups account for a large proportion of the gene mutations. Direct detection of these mutations can be used for the diagnosis of Parkinson's disease. Methods To detect these mutations, we developed an effective technique based on the real-time TaqMan PCR system, which allows us to evaluate the copynumbers of the PARK2 gene exons by comparing the intensity of the amplification signals from some exon of this gene with that of the β-globin gene (the internal control). Results We analyzed rearrangements in exons 1–12 of the PARK2 gene in 64 patients from Russia with early-onset Parkinson's disease. The frequency of these mutations in our patients was 14%. Conclusion We have developed a simple, accurate, and reproducible method applicable to the rapid detection of exon rearrangements in the PARK2 gene. It is suitable for the analysis of large patient groups, and it may become the basis for a diagnostic test.

A study of the immunomodulating effect of selank showed that both the total peptide and its fragment significantly change the expression of the genes for chemokines, cytokines, and their receptors in mouse spleen 6 and 24 h after single administration. Changes in the mRNA level of the majority of the genes under study were observed after the administration of Gly-Pro, which was earlier identified as a selank pharmacophore, a minimum fragment with anitiviral activity.

Background The nootropic neuroprotective peptide Semax (Met-Glu-His-Phe-Pro-Gly-Pro) has proved efficient in the therapy of brain stroke; however, the molecular mechanisms underlying its action remain obscure. Our genome-wide study was designed to investigate the response of the transcriptome of ischemized rat brain cortex tissues to the action of Semax in vivo. Results The gene-expression alteration caused by the action of the peptide Semax was compared with the gene expression of the “ischemia” group animals at 3 and 24 h after permanent middle cerebral artery occlusion (pMCAO). The peptide predominantly enhanced the expression of genes related to the immune system. Three hours after pMCAO, Semax influenced the expression of some genes that affect the activity of immune cells, and, 24 h after pMCAO, the action of Semax on the immune response increased considerably. The genes implicated in this response represented over 50% of the total number of genes that exhibited Semax-induced altered expression. Among the immune-response genes, the expression of which was modulated by Semax, genes that encode immunoglobulins and chemokines formed the most notable groups. In response to Semax administration, 24 genes related to the vascular system exhibited altered expression 3 h after pMCAO, whereas 12 genes were changed 24 h after pMCAO. These genes are associated with such processes as the development and migration of endothelial tissue, the migration of smooth muscle cells, hematopoiesis, and vasculogenesis. Conclusions Semax affects several biological processes involved in the function of various systems. The immune response is the process most markedly affected by the drug. Semax altered the expression of genes that modulate the amount and mobility of immune cells and enhanced the expression of genes that encode chemokines and immunoglobulins. In conditions of rat brain focal ischemia, Semax influenced the expression of genes that promote the formation and functioning of the vascular system. The immunomodulating effect of the peptide discovered in our research and its impact on the vascular system during ischemia are likely to be the key mechanisms underlying the neuroprotective effects of the peptide.

Several studies examined the fine-scale structure of human genetic variation in Europe. However, the European sets analyzed represent mainly northern, western, central, and southern Europe. Here, we report an analysis of approximately 166,000 single nucleotide polymorphisms in populations from eastern (northeastern) Europe: four Russian populations from European Russia, and three populations from the northernmost Finno-Ugric ethnicities (Veps and two contrast groups of Komi people). These were compared with several reference European samples, including Finns, Estonians, Latvians, Poles, Czechs, Germans, and Italians. The results obtained demonstrated genetic heterogeneity of populations living in the region studied. Russians from the central part of European Russia (Tver, Murom, and Kursk) exhibited similarities with populations from central-eastern Europe, and were distant from Russian sample from the northern Russia (Mezen district, Archangelsk region). Komi samples, especially Izhemski Komi, were significantly different from all other populations studied. These can be considered as a second pole of genetic diversity in northern Europe (in addition to the pole, occupied by Finns), as they had a distinct ancestry component. Russians from Mezen and the Finnic-speaking Veps were positioned between the two poles, but differed from each other in the proportions of Komi and Finnic ancestries. In general, our data provides a more complete genetic map of Europe accounting for the diversity in its most eastern (northeastern) populations.