[A mucosal melanoma of the larynx (a case report)]. / Nabliudenie melanomy slizistoi obolochki gortani.

In this article describe the clinical case of treatment of melanoma of the larynx mucous membrane.Presented the clinic, immunohistochemistrydiagnostics and methods of surgical treatment.

[Restoration of voice function in patients without larynx and pharyx: myth or reality?].

The article presents an original technique of voice restoration in patients who have undergone laryngopharyngectomy with resection of esophageal cervical part; analyses mechanism of phonation. Four cases of prosthetic reconstruction are reported. The necessity and feasibility of voice rehabilitation in patients with this severe condition are validated.

PP2A-Bgamma subunit and KCNQ2 K+ channels in bipolar disorder.

Many bipolar affective disorder (BD) susceptibility loci have been identified but the molecular mechanisms responsible for the disease remain to be elucidated. In the locus 4p16, several candidate genes were identified but none of them was definitively shown to be associated with BD. In this region, the PPP2R2C gene encodes the Bgamma-regulatory subunit of the protein phosphatase 2A (PP2A-Bgamma). First, we identified, in two different populations, single nucleotide polymorphisms and risk haplotypes for this gene that are associated to BD. Then, we used the Bgamma subunit as bait to screen a human brain cDNA library with the yeast two-hybrid technique. This led us to two new splice variants of KCNQ2 channels and to the KCNQ2 channel itself. This unusual K+ channel has particularly interesting functional properties and belongs to a channel family that is already known to be implicated in several other monogenic diseases. In one of the BD populations, we also found a genetic association between the KCNQ2 gene and BD. We show that KCNQ2 splice variants differ from native channels by their shortened C-terminal sequences and are unique as they are active and exert a dominant-negative effect on KCNQ2 wild-type (wt) channel activity. We also show that the PP2A-Bgamma subunit significantly increases the current generated by KCNQ2wt, a channel normally inhibited by phosphorylation. The kinase glycogen synthase kinase 3 beta (GSK3beta) is considered as an interesting target of lithium, the classical drug used in BD. GSK3beta phosphorylates the KCNQ2 channel and this phosphorylation is decreased by Li+.

Genetic analysis of case/control data using estimated haplotype frequencies: application to APOE locus variation and Alzheimer's disease.

There is growing debate over the utility of multiple locus association analyses in the identification of genomic regions harboring sequence variants that influence common complex traits such as hypertension and diabetes. Much of this debate concerns the manner in which one can use the genotypic information from individuals gathered in simple sampling frameworks, such as the case/control designs, to actually assess the association between alleles in a particular genomic region and a trait. In this paper we describe methods for testing associations between estimated haplotype frequencies derived from multilocus genotype data and disease endpoints assuming a simple case/control sampling design. These proposed methods overcome the lack of phase information usually associated with samples of unrelated individuals and provide a comprehensive way of assessing the relationship between sequence or multiple-site variation and traits and diseases within populations. We applied the proposed methods in a study of the relationship between polymorphisms within the APOE gene region and Alzheimer's disease. Cases and controls for this study were collected from the United States and France. Our results confirm the known association between the APOE locus and Alzheimer's disease, even when the epsilon 4 polymorphism is not contained in the tested haplotypes. This suggests that, in certain situations, haplotype information and linkage disequilibrium-induced associations between polymorphic loci that neighbor loci harboring functional sequence variants can be exploited to identify disease-predisposing alleles in large, freely mixing populations via estimated haplotype frequency methods.

Restrained chondrocyte proliferation and maturation with abnormal growth plate vascularization and ossification in human FGFR-3(G380R) transgenic mice.

Achondroplasia, the most common genetic form of human dwarfism, results from a point mutation (G380R) in the gene for fibroblast growth factor receptor 3 (FGFR-3). Heterozygotes for the mutation share disproportionate, proximal shortening of the limbs, mid-face hypoplasia and relative macrocephaly due to a failure in endochondral ossification. Here we have generated transgenic mice expressing the human mutant FGFR-3 under the transcriptional control of the mouse gene. Mice that are hemizygous for the mutant human gene display disproportionate dwarfism with skeletal phenotypes remarkably similar to those of human achondroplasia. Mice that are homozygous for the transgene suffer from a profound delay in skeletal development and die at birth, similar in that respect to humans homozygous for the achondroplasia mutant gene. Microscopic analysis of long bones demonstrates growth plate morphology compatible with that of human achondroplasia cases, sharing endochondral growth inhibition with restrained chondrocyte proliferation and maturation, penetration of ossification tufts and aberrant vascularization.

Predisposing gene for early-onset prostate cancer, localized on chromosome 1q42.2-43.

There is genetic predisposition associated with >=10% of all cancer of the prostate (CaP). By means of a genomewide search on a selection of 47 French and German families, parametric and nonparametric linkage (NPL) analysis allowed identification of a locus, on chromosome 1q42.2-43, carrying a putative predisposing gene for CaP (PCaP). The primary localization was confirmed with several markers, by use of three different genetic models. We obtained a maximum two-point LOD score of 2.7 with marker D1S2785. Multipoint parametric and NPL analysis yielded maximum HLOD and NPL scores of 2.2 and 3.1, respectively, with an associated P value of . 001. Homogeneity analysis with multipoint LOD scores gave an estimate of the proportion of families with linkage to this locus of 50%, with a likelihood ratio of 157/1 in favor of heterogeneity. Furthermore, the 9/47 families with early-onset CaP at age <60 years gave multipoint LOD and NPL scores of 3.31 and 3.32, respectively, with P = .001.

Characterization of a YAC contig containing the NBCCS locus and a novel Kruppel-type zinc finger sequence on chromosome segment 9q22.3.

Gorlin's syndrome or nevoid basal cell carcinoma syndrome (NBCCS) is an autosomal dominant disorder characterized by a familial or hereditary predisposition to basal cell carcinomas (generally multiple and of early onset), odontogenic keratocysts (jaw cysts), palmar and plantar pits, a wide variety of developmental defects, as well as cancers such as medulloblastomas and ovarian fibromas. The gene for NBCCS has been mapped to human chromosome region 9q22.1-q31 by linkage analysis and by cytogenetic evidence of deletions in this region in patients with the syndrome. This is supported by loss of heterozygosity in tumors of polymorphic marker loci flanked by D9S197 and D9S180. We have utilized sequence tagged site (STS) mapping and somatic cell hybrid panel analysis to construct two overlapping yeast artificial chromosome (YAC) contigs spanning this region of the genome. We used the YAC contigs to identify a new zinc finger gene containing a highly informative microsatellite locus.

Recombinational and physical mapping of the locus for primary open-angle glaucoma (GLC1A) on chromosome 1q23-q25.

Primary open-angle glaucoma (POAG) is a leading cause of irreversible blindness in industrialized countries. A locus for juvenile-onset POAG, GLC1A, has been mapped to 1q21-q31 in a 9-cM interval. With recombinant haplotypes, we have now reduced the GLC1A interval to a maximum of 3 cM, between the D1S452/NGA1/D1S210 and NGA5 loci. These loci are 2.8 Mb apart on a 4.7-Mb contig that we have completed between the D1S2851 and D1S218 loci and that includes 96 YAC clones and 48 STSs. The new GLC1A interval itself is now covered by 25 YACs, 30 STSs, and 16 restriction enzyme site landmarks. The lack of a NotI site suggests that the region has few CpG islands and a low gene content. This is compatible with its predominant cytogenetic location on the 1q24 G-band. Finally, we have excluded important candidate genes, including genes coding for three ATPases (ATP1B1, ATP2B4, ATP1A2), an ion channel (VDAC4), antithrombine III (AT3), and prostaglandin synthase (PTGS2). Our results provide a basis to identify the GLC1A gene.

[Test results on the insecticidal activity of Oradelt and Omait against rodent fleas]. / Rezul'taty ispytaniia insektitsidnoi aktivnosti oradel'ya i omaita v otnoshenii blokh gryzunov.

The paper presents the results of trials of the commercial agents oraldelt and omaita as an insecticide against rodent fleas. The agents were found to produce highly toxic effects on fleas. The field trials established the high poolecidal effectivity of oraldelt in the mountain suslik habitats. The commercial agent oraldelt containing 0.05% of decamethrin may be recommended for the control of fleas in the foci of suslik-type plague.

The organization of the human gene NCX1 encoding the sodium-calcium exchanger.

The intron-exon organization of the human Na/Ca-exchanger gene NCX1 and of the N-terminal half of the related gene NCX2 has been determined. The NCX1 gene consists of 12 exons spread over 200 kb on chromosome 2 close to STS D2S2328 and encodes a 6.2-kb transcript. Both NCX1 and NCX2 feature an unusual 1.8-kb exon, containing two-thirds of the protein coding sequence and a similar area of the coding sequences split into several small exons, displaying tissue-specific alternative splicing. The similar intron positions in the "cardiac" (NCX1) and "brain" (NCX2) mammalian exchanger genes suggest their origin from the recent duplication and translocation of a common ancestral gene, a putative precursor of which has been identified in the nematode Caenorhabditis elegans.

Activation of the human homologue of the Drosophila sina gene in apoptosis and tumor suppression.

Developmentally regulated genes in Drosophila, which are conserved through evolution, are potential candidates for key functions in biological processes such as cell cycle, programmed cell death, and cancer. We report cloning and characterization of the human homologue of the Drosophila seven in absentia gene (HUMSIAH), which codes for a 282 amino acids putative zinc finger protein. HUMSIAH is localized on human chromosome 16q12-q13. This gene is activated during the physiological program of cell death in the intestinal epithelium. Moreover, human cancer-derived cells selected for suppression of their tumorigenic phenotype exhibit constitutively elevated levels of HUMSIAH mRNA. A similar pattern of expression is also displayed by the p21waf1. These results suggest that mammalian seven in absentia gene, which is a target for activation by p53, may play a role in apoptosis and tumor suppression.

Survey of CAG/CTG repeats in human cDNAs representing new genes: candidates for inherited neurological disorders.

Expansion of polymorphic CAG and CTG repeats in transcripts is the cause of six inherited neurodegenerative or neuromuscular diseases and may be involved in several other genetic disorders of the central nervous system. To identify new candidate genes, we have undertaken a large-scale screening project for CAG and CTG repeats in human reference cDNAs. We screened 100 128 brain cDNAs by hybridization. We also scanned GenBank expressed sequence tags for the presence of long CAG/CTG repeats in the extremities of cDNAs from several human tissues. Of the selected clones, 286 were found to represent new genes, and 72 have thus far been shown to contain CAG/CTG repeats. Our data indicate that CAG/CTG repeated 10 or more times are more likely to be polymorphic, and that new 3'-directed cDNAs with such repeats are very rare (1/2862). Nine new cDNAs containing polymorphic (observed heterozygote frequency: 0.05-0.90) CAG/CTG repeats have been currently identified in cDNAs. All of the cDNAs have been assigned to chromosomes, and six of them could be mapped with YACs to 1q32-q41, 3p14, 4q28, 3p21 and 12q13.3, 13q13.1-q13.2, and 19q13.43. Three of these clones are highly polymorphic and represent the most likely candidate genes for inherited neurodegenerative diseases and, perhaps, neuropsychiatric disorders of multifactorial origin.

Linkage of polymorphic congenital cataract to the gamma-crystallin gene locus on human chromosome 2q33-35.

Cataract is one of the major causes of blindness in humans. We describe here an autosomal dominant polymorphic congenital cataract (PCC) which is characterised by wide variations in phenotype of non-nuclear lens opacities, even among affected members of the same family. PCC families included a large, unique pedigree (254 members, 103 affected individuals), and genetic linkage was conducted using a variety of polymorphic markers. Evidence for linkage was found for chromosome 2q33-35 with PCC mapping near D2S72 and TNP1. A tri-nucleotide microsatellite marker for gamma-crystallin B gene (CRYG1) was found to co-segregate with PCC and yielded a maximum lod score of 10.62 at (theta = 0). A multipoint analysis demonstrated that the most probable location of the PCC gene was within an 8 cM genetic interval containing the gamma-crystallin gene cluster. These data provide strong evidence of the existence of an autosomal dominant mutation for PCC in or near the gamma-crystallin gene cluster. This defect is characterised by complete penetrance but variable expression of the cataract phenotype. Our study also suggests that non-nuclear human cataracts might be caused by some abnormality in gamma-crystallin genes.

Identification of three new microsatellite markers in the spinocerebellar ataxia type 2 (SCA2) region and 1.2 Mb physical map.

Spinocerebellar ataxia type 2 (SCA2) is a neurodegenerative disease recently mapped to chromosome 12q close to the locus D12S84 by genetic linkage analysis. To generate additional genetic markers in the SCA2 region, we constructed a physical map of the region using yeast artificial chomosome (YAC), P1 artificial chromosome (PAC) and cosmid clones. The physical map was found to agree well with the genetic map. Three novel microsatellite markers were isolated and physically mapped. A novel approach to isolate CAG repeats directly from YAC DNAs is described.

A 1.6-Mb P1-based physical map of the Down syndrome region on chromosome 21.

The Down syndrome (DS) region on chromosome 21, which is responsible for the main features of DS such as characteristic facial features, a congenital heart defect, and mental retardation, has been defined by molecular analysis of DS patients with partial trisomy 21. The 2. 5-Mb region around the marker D21S55 between D21S17 and ERG in 21q22 is thought to be important, although contributions of other regions cannot be excluded. In this region, we focused on a 1.6-Mb region between a NotI site, LA68 (D21S396, which is mapped distal to D21S17) and ERG, because analysis of a Japanese DS family with partial trisomy 21 revealed that the proximal border of its triplicated region was distal to LA68. We constructed P1 contigs with 46 P1 clones covering more than 95% of the 1.6-Mb region. A high-resolution restriction map using BamHI was also constructed for more detailed analysis. Our P1 contig map supplements other physical maps previously reported and provides useful materials for further analysis including gene isolation and sequencing of the DS region.

Molecular biological studies of the cardiac sodium-calcium exchanger.

The intron-exon organization of the entire human Na-Ca-exchanger gene NCX1 and of the central part of the related gene NCX2 has been determined. The NCX1 gene is at least 75 kb long and consists of at least 12 exons, the two largest (the 2nd and the 12th) coding for the N-terminal half of the exchanger sequence and for the last three C-terminal transmembrane domains. They also code for the 3.3-kb 3'-untranslated region and account for more than 90% of the length of the mature mRNA. The remainder of the NCX1 (NCX2) gene, coding for a putative cytoplasmic regulatory domain, is split into 9 (7) small exons. In spite of the limited (65%) average homology of the two cDNAs, analogous exons are readily identified within this portion of the two genes based on their high (80-95%) pairwise homology and similar patterns of differential splicing in brain. Human YAC clones have been identified in the CEPH library, which contain the entire NCX1/2 and NCKX1 (retinal rod exchanger) genes, and are used for chromosomal localization of the three genes. A distant homolog of the mammalian NCX genes has been identified in the C. elegans EST database and has been completely sequenced. It encodes a 20% shorter protein, which has an average 55% homology to human NCX1, and lacks most of the region that is known to be encoded by multiple differentially spliced exons in vertebrates. Comparison of available data on the gene structure of the NCX homologs in various species suggests that this protein has emerged in the primitive nervous system and has been subsequently adapted to other cellular environments by the use of novel domains, encoded in additional exons.

Integration of 30 CA-repeat markers into the cytogenetic, genetic and YAC maps of human chromosome 21.

The number of polymorphic DNA markers developed for the whole human genome during the last 2 years has been vastly increased. For this reason, the genetic map is continuously improving, but the cytogenetic and physical maps are not progressing at the same speed. Therefore, there is a need to integrate genetic, cytogenetic and physical mapping data. We have developed and localized on the breakpoint map of human chromosome 21 thirty microsatellite markers. Twenty of them have been used in the construction of a genetic map of chromosome 21, which contains a total of 44 markers. This map has 39 uniquely placed loci at 23 anchor points, ordered with odds of at least 1,000:1. The sex average length of the map is 64.4 cM, with the male and female lengths being 49.4 and 79.2 cM, respectively. Twenty-six of these newly developed markers have been localised on the CEPH/Généthon and Joint YAC Screening Effort YACs. Although these microsatellites were found uniformly spread along chromosome 21, the detection of various markers in the same or adjacent YACs suggests that CA-repeat microsatellites are clustered in several regions. The localization of these markers on the cytogenetic, genetic and YAC maps has provided a refined location for them and is a step further towards the construction of an integrated map of HC21.

A high-fidelity physical map of human chromosome 21q in yeast artificial chromosomes.

Understanding of the human genome has been advanced significantly by the development of large DNA fragment libraries. To create a map of chromosome 21q that integrates the physical, cytogenetic, and linkage maps, we have characterized a subset of 127 chromosome 21 yeast artificial chromosome (YAC) clones for size, by pulsed field gel electrophoresis, for chimerism and cytogenetic location, by fluorescence in situ hybridization (FISH), and for sequence-tagged sites (STS) content, by PCR. It was found that 54% generated unique map locations on chromosome 21, and 45% detected sites on other chromosomes, of which 33% likely represented true chimerism. Using a simple algorithm, the data from nonchimeric clones have been combined to generate a size-corrected minimal tiling pathway including 58 chromosome 21q YACs that represent approximately 33 Mb and include 9 gaps. To confirm the resulting order and relationship to the cytogenetic map, the breakpoints from 23 cell lines partially aneuploid for chromosome 21 have been analyzed by quantitative Southern blot dosage analysis and FISH with a subset of the markers. As one way of investigating the relationship of the genetic to the physical map, the genetic map was superimposed on the physical map using a subset of well-defined markers common to both. The results suggest potential hot spots for recombination and/or gaps in the physical map. This integrated map will facilitate the search for the genes responsible for the Down syndrome phenotypes and provide a better understanding of genome organization and chromosome structure.