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INTRODUCTION: Comparative cytogenetics is a vital approach for diagnosing chromosome abnormalities and identifying species-specific patterns. In this study, chromosomal analysis of three Anatolian endemic Cobitis species was performed: Cobitis bilseli, C. fahireae, and C. turcica. METHODS: Conventional cytogenetic techniques such as Giemsa staining, C-banding, and Ag-NOR staining were applied, followed by measurements of chromosome arm lengths including analysis of the measured data. RESULTS: The diploid chromosome number, 2n = 50, was determined for all three species. The karyotype formulas were as follows: four pairs of metacentric, 5 pairs of submetacentric, and 16 pairs of subtelo-telocentric chromosomes in C. bilseli; 11 pairs of metacentric, 7 pairs of submetacentric, and 7 pairs of subtelo-telocentric chromosomes in C. fahireae; and 4 pairs of metacentric, 4 pairs of submetacentric, and 17 pairs of subtelo-telocentric chromosomes in C. turcica. Dark C-bands were observed on the pericentromeres of nearly all chromosomes in C. bilseli and C. turcica, whereas light C-bands appeared on the pericentromeres of some chromosomes in C. fahireae. Silver-stained metaphases revealed signals on the short arm of a submetacentric chromosome pair in C. fahireae (each homologous chromosome carries one signal), while in C. bilseli and C. turcica, Ag-NOR signals were detected on the long arm of a single metacentric chromosome (only one homologous chromosome carries the signal, and the signal-carrying chromosome is the largest chromosome in the karyotype). CONCLUSION: This study provides new cytogenetic data consistent with the phylogenetic distances between the studied species, indicating that pericentric inversions and/or translocations govern the formation of Cobitis karyotypes. INTRODUCTION: Comparative cytogenetics is a vital approach for diagnosing chromosome abnormalities and identifying species-specific patterns. In this study, chromosomal analysis of three Anatolian endemic Cobitis species was performed: Cobitis bilseli, C. fahireae, and C. turcica. METHODS: Conventional cytogenetic techniques such as Giemsa staining, C-banding, and Ag-NOR staining were applied, followed by measurements of chromosome arm lengths including analysis of the measured data. RESULTS: The diploid chromosome number, 2n = 50, was determined for all three species. The karyotype formulas were as follows: four pairs of metacentric, 5 pairs of submetacentric, and 16 pairs of subtelo-telocentric chromosomes in C. bilseli; 11 pairs of metacentric, 7 pairs of submetacentric, and 7 pairs of subtelo-telocentric chromosomes in C. fahireae; and 4 pairs of metacentric, 4 pairs of submetacentric, and 17 pairs of subtelo-telocentric chromosomes in C. turcica. Dark C-bands were observed on the pericentromeres of nearly all chromosomes in C. bilseli and C. turcica, whereas light C-bands appeared on the pericentromeres of some chromosomes in C. fahireae. Silver-stained metaphases revealed signals on the short arm of a submetacentric chromosome pair in C. fahireae (each homologous chromosome carries one signal), while in C. bilseli and C. turcica, Ag-NOR signals were detected on the long arm of a single metacentric chromosome (only one homologous chromosome carries the signal, and the signal-carrying chromosome is the largest chromosome in the karyotype). CONCLUSION: This study provides new cytogenetic data consistent with the phylogenetic distances between the studied species, indicating that pericentric inversions and/or translocations govern the formation of Cobitis karyotypes.
- Klíčová slova
- Ag-NORs, C-banding, Centromeric index, Fish, Spined loach,
- MeSH
- chromozomy genetika MeSH
- diploidie MeSH
- druhová specificita MeSH
- karyotyp * MeSH
- karyotypizace MeSH
- pruhování chromozomů MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Turecko MeSH
Multilocus hybrid zone (HZ) studies predate genomics by decades. The power of early methods is becoming apparent and now large datasets are commonplace. Relating introgression along a chromosome to evolutionary process is challenging: although reduced introgression regions may indicate speciation genes, this pattern may be obscured by asymmetric introgression of linked invasive genes. Further, HZ movement may form salients and leave islands in its wake. Barton's concordance was proposed 24 years ago for assessing introgression where geographic patterns are complex. The geographic axis of introgression is replaced with the hybrid index. We compare this, a recently proposed genomic clines approach, and two-dimensional (2D) geographic analyses, for 24 X chromosome loci of 2873 mice from the central-European house mouse HZ. In 2D, 14 loci show linear contact, seven precisely matching previous studies. Four show introgression islands to the east of the zone, suggesting past westward zone movement, two show westward salients. Barton's concordance both recovers and refines this information. A region of reduced introgression on the central X is supported, despite X centromere-proximal male-biased westward introgression matching a westward 2D geographic salient. Genomic clines results are consistent regarding introgression asymmetries, but otherwise more difficult to interpret. Evidence for genetic conflict is discussed.
- MeSH
- chromozom X genetika MeSH
- druhová specificita MeSH
- genetická variace MeSH
- hybridizace genetická * MeSH
- myši genetika MeSH
- populační genetika * MeSH
- rozmnožování MeSH
- savčí chromozomy genetika MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši genetika MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
- Německo MeSH
Understanding the origin and evolution of sex chromosomes requires studying recently evolved X-Y chromosome systems such as those in some flowering plants. We describe Y chromosome deletion mutants of Silene latifolia, a dioecious plant with heteromorphic sex chromosomes. The combination of results from new and previously described deletions with histological descriptions of their stamen development defects indicates the presence of two distinct Y regions containing loci with indispensable roles in male reproduction. We determined their positions relative to the two main sex determination functions (female suppressing and the other male promoting). A region proximal to the centromere on the Y p arm containing the putative stamen promoting sex determination locus includes additional early stamen developmental factors. A medial region of the Y q arm carries late pollen fertility factors. Cytological analysis of meiotic X-Y pairing in one of the male-sterile mutants indicates that the Y carries sequences or functions specifically affecting sex chromosome pairing.
- MeSH
- biologická evoluce * MeSH
- DNA rostlinná genetika MeSH
- druhová specificita MeSH
- genetická variace MeSH
- mutace MeSH
- pohlavní chromozomy genetika MeSH
- rekombinace genetická * MeSH
- rostlinné geny genetika MeSH
- rozmnožování genetika MeSH
- selekce (genetika) MeSH
- Silene genetika MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- DNA rostlinná MeSH
BACKGROUND: A cytogenetic analysis of the new local triploid population of the caryophyllidean tapeworm Atractolytocestus huronensis, a unique parthenogenetic species with the ability to colonise new regions, was performed to understand the inner structure of its chromosome complement. METHODS: A karyotype analysis was carried out using classical Giemsa staining and C-banding combined with fluorescent DAPI staining. A hypothesis that triplets are composed from three homologue chromosomes of approximately the same length and same centromere position was tested statistically for multiple dependent variables using a non-parametric Friedman's ANOVA. The chromosomal location of ribosomal DNA clusters within the nucleolar organization region (NORs) and telomeric (TTAGGG)n sequences were detected by fluorescent in situ hybridization (FISH). Chromosomes were subjected to AgNO3 staining in order to determine whether the rDNA sites represent active NORs. RESULTS: The cytogenetic analysis confirmed the karyotype composed from eight chromosome triplets (3n = 24) as well as the existence of a pair of NORs located on each chromosome of the second triplet. Six NORs varied their activity from cell to cell, and it was reflected in the numbers of nucleoli (from 1 to 5). A huge morphological diversification of homologue chromosomes was originally detected in six out of eight triplets; the homologue elements differed significantly either in length and/or morphology, and some of them carried discernible interstitial telomeric sequences (ITSs), while the end telomeres were minute. The heterochromatin bands with high AT content varied irregularly, and the course of aberrant spermatogenesis was evident. CONCLUSIONS: Diversification of homologues is a unique phenomenon very likely caused by the long-term absence of a recombination and consequential accumulation of chromosome rearrangements in the genome of A. huronensis during species evolution. Unalterable asexual reproduction of the tapeworm, along with international trade in its host (carp), is facilitating its ongoing spread.
- Klíčová slova
- Aberrant meiosis, Cestoda, Diversification of homologues, Interstitial telomere sequences (ITSs), Polyploidy,
- MeSH
- Cestoda klasifikace genetika fyziologie MeSH
- chromozomy MeSH
- kapři parazitologie MeSH
- karyotypizace MeSH
- nemoci ryb parazitologie MeSH
- rozmnožování MeSH
- spermatocyty cytologie MeSH
- triploidie MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Charcot-Marie-Tooth (CMT) disease is a heterogeneous disorder of the peripheral nervous system that collectively affects approximately 1 in 2,500 individuals, thus making it the most common inherited neurologic disorder. X-linked inheritance may account for 10-20 % of CMT neuropathy. We report a Czech family with a 30-year-old woman affected by CMT since the age of 10 years, originally as an isolated case. Nerve conduction study (NCS) showed demyelinating neuropathy, and DNA testing revealed a novel heterozygous gap junction beta-1 protein (GJB1) mutation c.784_786delTA. The same mutation, but surprisingly in heterozygous state, was subsequently found in her subjectively healthy father and later also in one of her sisters but not in her two other sisters. NCS showed intermediate type of motor and sensory neuropathy in these two females manifesting heterozygotes and normal results in the other healthy sisters and one brother, all without the c.784_786delTA mutation. The father has a phenotype milder than his daughter and has only subclinical signs of CMT. The index female patient had normal karyotype 46, XX, and normal FISH for centromeric X chromosome. We concluded that the proband's father is a heterozygote due to the somatic mosaicism for the GJB1 mutation in his leukocytes (detected by DNA sequencing) and also in his germ cells as confirmed by the unexpectedly different genotypes in his four daughters. Quantitative analysis revealed a mutated signal in 25:75 allele proportion of mutated to healthy allele in the mosaic father. This study has important consequences for genetic counseling and prognosis in CMTX1 families.
- MeSH
- Charcotova-Marieova-Toothova nemoc diagnóza genetika MeSH
- dospělí MeSH
- geny vázané na chromozom X MeSH
- heterozygot * MeSH
- konexiny genetika MeSH
- lidé středního věku MeSH
- lidé MeSH
- mozaicismus * MeSH
- periferní nervy patofyziologie MeSH
- protein beta 1 mezerového spoje MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- kazuistiky MeSH
- Research Support, N.I.H., Extramural MeSH
- Geografické názvy
- Česká republika MeSH
- Názvy látek
- konexiny MeSH
The widely distributed ray-finned fish genus Carassius is very well known due to its unique biological characteristics such as polyploidy, clonality, and/or interspecies hybridization. These biological characteristics have enabled Carassius species to be successfully widespread over relatively short period of evolutionary time. Therefore, this fish model deserves to be the center of attention in the research field. Some studies have already described the Carassius karyotype, but results are inconsistent in the number of morphological categories for individual chromosomes. We investigated three focal species: Carassius auratus, C. carassius and C. gibelio with the aim to describe their standardized diploid karyotypes, and to study their evolutionary relationships using cytogenetic tools. We measured length (q+plength) of each chromosome and calculated centromeric index (i value). We found: (i) The relationship between q+plength and i value showed higher similarity of C. auratus and C. carassius. (ii) The variability of i value within each chromosome expressed by means of the first quartile (Q1) up to the third quartile (Q3) showed higher similarity of C. carassius and C. gibelio. (iii) The fluorescent in situ hybridization (FISH) analysis revealed higher similarity of C. auratus and C. gibelio. (iv) Standardized karyotype formula described using median value (Q2) showed differentiation among all investigated species: C. auratus had 24 metacentric (m), 40 submetacentric (sm), 2 subtelocentric (st), 2 acrocentric (a) and 32 telocentric (T) chromosomes (24m+40sm+2st+2a+32T); C. carassius: 16m+34sm+8st+42T; and C. gibelio: 16m+22sm+10st+2a+50T. (v) We developed R scripts applicable for the description of standardized karyotype for any other species. The diverse results indicated unprecedented complex genomic and chromosomal architecture in the genus Carassius probably influenced by its unique biological characteristics which make the study of evolutionary relationships more difficult than it has been originally postulated.
- Klíčová slova
- Carassius auratus, Carassius carassius, Carassius gibelio, chromosome, i value, in situ hybridization, karyogram, q/p arm ratio,
- MeSH
- chromozomy genetika MeSH
- diploidie MeSH
- fylogeneze MeSH
- genetická variace genetika MeSH
- genom genetika MeSH
- hybridizace in situ fluorescenční metody MeSH
- kapři genetika MeSH
- karas zlatý genetika MeSH
- karyotyp MeSH
- karyotypizace metody MeSH
- mapování chromozomů metody MeSH
- polyploidie MeSH
- ryby genetika MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Antinuclear antibodies are a group of autoantibodies which are typical for collagenous diseases. By means of the autoantibody profile different sub-groups of systemic lupus erythematosus (SLE) can be identified. This can serve as a certain prognostic factor of the affection. Patients with a negative antibody profile have fewer clinical and laboratory manifestations of SLE. Profile A (anti-dsDNA and/or anti-Sm has, as compared with patients with a negative antibody profile, more frequent organ manifestations. Patients with profile B (anti-RNP) have a higher frequency of Raynaud's phenomenon. Profile C (anti-Ro, anti-La) is characterized in particular by photosensitivity of the skin and secondary Sjögren's syndrome. Profile D (antibodies against centromeres and/or Scl-70) are found in subjects with SLE with traits of scleroderma. Finally profile E (antibodies against histones) are found in SLE induced by drugs. In the submitted study in 28 patients with SLE autoantibodies anti-dsDNA, anti-DNP, extracted nuclear antibodies (ENA-Sm,Ro,La, histones, Sm/RNP, Scl-70) were evaluated and different subgroups of SLE were assessed. Attention was paid to their common characteristics and the activity of the disease. Associations of clinical activity of the disease expressed by the ECLAM index (European Consensus Lupus Activity Measurement) were tested as well as anti-dsDNA levels and also the association of the disease activity with C3 and C4 constituents of complement, CRP and circulating immunocomplexes in serum. Positivity of the antinuclear factor (ANF) was found in 21 patients, while in 7 subjects who were in clinical and laboratory remission, ANF was negative. A negative antibody profile was recorded in 9 patients, profile A was found in 13, 1 patient had profile B, and 4 patients had profile C. Antibody profile D was not found in the group. When using regression analysis and Pearson s correlation coefficient, correlations were found between anti-dsDNA values and the system ECLAM (r = 0.72, p < 0.01), anti-dsDNA and C3 levels (r = -0.59, p < 0.01), C4 (r = -0.50,, p < 0.01), and between the ECLAM system and C3 (r = -0.60, p 0.01) and C4 (r = -0.52, p < 0.01) and also between C3 and C4 mutually (r = 0.72, p < 0.01). From the submitted investigation ensues that investigation of antinuclear antibody levels in SLE is important not only for assessment of the diagnosis of the disease and its activity but also for assessment of the subgroups of the disease and for prediction of its development. As to other indicators of activity, assessment of the C3 and C4 constituents of complement is still important.
- MeSH
- antinukleární protilátky analýza MeSH
- autoprotilátky analýza MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- senioři MeSH
- systémový lupus erythematodes diagnóza imunologie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- anglický abstrakt MeSH
- časopisecké články MeSH
- Názvy látek
- antinukleární protilátky MeSH
- autoprotilátky MeSH