Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Inversion”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,117 records · Page 62Linked to original sources

BAC clones and STS markers near the distal breakpoint of the fourth t-inversion, In(17)4d, in the H2-M region on mouse chromosome 17.

The H2-M region is the most distal part of the mouse major histocompatibility complex (Mhc) and is likely to include the distal breakpoint of the fourth t-inversion, In(17)4d. The conserved synteny breakpoint between mouse and human is located in the H2-M region between D17Leh89, a putative olfactory receptor gene, and Pgk2 (phosphoglycerate kinase 2). To analyze the H2-M region, we screened a mouse bacterial artificial chromosome (BAC) library, using the D17Mit64, D17Tu49, D17Leh89, D17Leh467, and Pgk2 markers. Thirty-eight BAC clones were obtained and mapped in five clusters, and 25 sequence-tagged site (STS) markers were newly developed. The regions surrounding D17Tu49 and D17Leh467 are abundant in L1 repeat sequences and may, therefore, be candidates for the breakpoints of conserved synteny and t-inversion. D17Leh89 was linked to D17Mit64 by two contiguous BAC clones. The Aeg1 (acidic epididymal glycoprotein 1) and Aeg2 genes were mapped close to Pgk2, on the same BAC clones. The genetic length between D17Leh89-D17Mit64 and Pgk2-Aeg can be estimated as 0.5-0.7 centiMorgan (cM), and the most distal class I gene, H2-M2, can be placed 0.3-1.0 cM proximal to the t-inversion breakpoint. A recombinational hotspot is suggested to be located between Aeg and Tpxl in an interspecific cross of (C57BL/6J x Mus spretus).

Animals↗

Pregnancy outcome after operative correction of puerperal uterine inversion.

Uterine inversion is an uncommon but life-threatening obstetric emergency. A review of the approaches to correct uterine inversion is presented. In cases where time has elapsed between delivery and presentation, the inversion ring may have become too tight to allow manual reposition of the fundus. In such cases, it has to be divided by a vertical incision. In subsequent pregnancy, antenatal care should include placental localization and planning for an elective Caesarean Section. The outcome of future pregnancies may be complicated by placenta accreta and massive haemorrhage.

Adult↗

Subterminal deletion/duplication event in an affected male due to maternal X chromosome pericentric inversion.

UNLABELLED: We report a 13-month-old male infant with an apparently normal karyotype, severe growth and developmental delay, ichthyosis, hypogonadism, limb shortness, hypoplasia of the corpus callosum and a round, flat face and thin upper lip as a consequence of a subtelomeric del/dup event of the X chromosome. The recombinant X chromosome (rec(X)), derived from crossing-over within the inversion, was identified in a family, in which the mother is a carrier of pericentric inversion of one X chromosome and pericentric inversion of the heterochromatic region of chromosome 9. The inv(X) chromosome was also analysed in her sister and daughter. The rec(X) had a duplication of the segment Xq27.3-->Xqter and deletion of the Xp22.31-->Xpter and was interpreted as Xqter-Xq27.3::Xp22.31-Xqter. The rec (X) was characterised by FISH using a number of BAC probes. There are only three published reports of chromosome rearrangements resulting in a similar subtelomeric duplication of Xq in males. The proband's phenotype corresponds to descriptions of contiguous gene syndromes due to deletion of the STS, SHOX, ARSE and KAL genes. Despite the loss of the ARSE gene there was no evidence of chondrodysplasia punctata. Additional conditions associated with duplication of the Xq28 segment, such as severe growth retardation and developmental delay, a peculiar head shape, atrophy of the cerebral hemispheres and hypoplasia of the cerebellum and corpus callosum, were observed. CONCLUSION: Fluorescent in situ hybridisation techniques using subtelomeric DNA probes are essential tools for detection of such complex submicroscopic chromosomal rearrangements as the dup/del event of the X chromosome described in our patient.

Adult↗

Interchromosomal effect leading to an increase in aneuploidy in sperm nuclei in a man heterozygous for pericentric inversion (inv 9) and C-heterochromatin.

We describe a man with pericentric inversion 9 and constitutive heterochromatin, and a high disomy rate in his sperm cells (with all probes analyzed). The disomy rate was estimated with the following probes: 8, 9, 18, X, and Y, and was significantly higher than that in control sperm cells, while chromosome 9 showed the highest disomy frequency. The probes of X and Y together showed the same disomy frequency as X and Y alone, which indicates the same nondisjunction rate in the first meiotic division. We suggest that the interchromosomal effect found in this man differed from other findings in sperm cells of men carrying an inversion in terms of the difference in the length of the heterochromatin between the two chromosomes 9. Also, it is well known that the effect of inversion 9 with increased heterochromatin is highly variable and may even vary in members of the same family.

Abortion, Spontaneous↗

Nonpuerperal inversion of the uterus associated with endometrial cancer: a case report.

Few nonpuerperal uterine inversions have been reported, with only 101 cases during the period from 1940 to date. Moreover, uterine inversion resulting from endometrial cancer is an extremely rare condition, with only 7 reported cases. In this article, we present a case of a patient with uterine inversion caused by endometrial cancer that could be diagnosed and treated with surgery. We also discuss the mechanism of onset and present a review of the literature.

Adenocarcinoma↗

Physical structures of Tn10-promoted deletions and inversions: role of 1400 bp inverted repetitions.

We report here the physical structures of deletions and inversions promoted by the translocatable tetracycline-resistance element Tn10. DNA/DNA heteroduplex and restriction enzyme analyses of alterations in the genome of bacteriophage lambda suggest that both types of DNA alterations almost always originate at the internal termini of the 1400 bp terminal inverted repetitions of Tn10. Tn10-promoted deletions remove a single contiguous DNA segment beginning at one such terminus; Tn10-promoted inversions are more complex, and involve both an inversion and a specific deletion of Tn10 DNA.

Chromosome Deletion↗

Structure and role of the herpes simplex virus DNA termini in inversion, circularization and generation of virion DNA.

The herpes simplex virus genome consists of two components, L and S, which invert relative to each other during viral replication. The a sequence is present at the genomic termini in direct orientation and at the L-S junction in inverted orientation. Previously, we showed that insertion of a fragment spanning the L-S junction into the viral genome causes additional inversions. In this study, we determine the nucleotide sequence of the genomic termini and show that insertion of either the free S terminus or the L terminus causes inversions in the viral genome. We conclude that the a sequence is the inversion-specific sequence, that linear unit-length molecules packaged in virions are generated by cleavage between adjacent copies of the a sequence, that cleavage produces 3' single-base extensions on the genomic termini and that the signal for cleavage is contained within the a sequence.

Animals↗

Genetic analysis of the proximal portion of the mouse t complex: evidence for a second inversion within t haplotypes.

Genomic sequences derived from the mouse t complex by a microdissection cloning technique have been used as tools to obtain high resolution genetic maps of the wild-type and t haplotype forms of the most proximal portion of chromosome 17. Genetic mapping was performed through a recombinant inbred strain analysis and an analysis of partial t haplotypes. The accumulated data demonstrate the existence of a large inversion of genetic material, encompassing the loci of T and qk, within the proximal portion of t haplotypes. This newly described proximal inversion and the previously described distal inversion provide an explanation for the suppression of recombination observed along the length of t haplotype DNA in heterozygous mice.

Animals↗

Host protein requirements for in vitro site-specific DNA inversion.

Flagellar phase variation is mediated by a recombination event that occurs at specific sites leading to inversion of a chromosomal segment of DNA. The presence of a 60 bp recombinational enhancer sequence on the DNA substrate molecule results in a 150-fold stimulation in the initial rate of inversion. The protein components required for inversion have been purified. They include the 21,000 dalton recombinase (Hin), a 12,000 dalton host protein (Factor II), and one of the major histone-like proteins of E. coli HU. The dependence of the initial rate of recombination on HU varies with respect to the location of the recombinational enhancer. The role of HU, Factor II, and the enhancer in facilitating site-specific recombination is discussed.

Bacterial Proteins↗

Constitutional interstitial deletion of 11p11 and pericentric inversion of chromosome 9 in a patient with Wiedemann-Beckwith syndrome and hepatoblastoma.

A constitutional interstitial deletion on the short arm of chromosome #11 and an inversion of the heterochromatin of chromosome #9 were detected in a 1.5-year-old boy with Wiedemann-Beckwith syndrome (WBS) and hepatoblastoma. Of 37 malignant and nine benign neoplasms reported in approximately 250 cases with complete and incomplete forms of WBS, this is the fourth patient with hepatoblastoma. To date, 28 cases of WBS have been cytogenetically investigated with banding techniques. Constitutional anomalies have been found in only nine cases: Various anomalies resulting in a common triplication of the 11p15 region in six cases, reciprocal translocations t(11;22) and t(X;1) and an inversion of chromosome #2 in the three remaining cases. Triplication 11p15 was only present in one of four cases with a tumor. The breakpoints of the unique del(11)(p11.1p11.2) present in our case are proximal to those of del(11p13-11p14) and dup(11p15) observed thus far in both the aniridia-Wilms' tumor association and in WBS. Inversion of chromosome #9--one of the heterochromatin variants associated with elevated chromosomal instability, increased congenital abnormalities, and cancer proneness--may have been causally connected with a genetic imbalance resulting in the de novo deletion of 11p11. Therefore, we suggest that in these high-risk groups, C-banding studies should be performed together with high resolution chromosome analysis in order to also reveal the incidence and significance of C-band variants in individuals with such cancer prone syndromes.

Beckwith-Wiedemann Syndrome↗

Inversion of chromosome 5 long arm in region of cell growth gene cluster in hematologic disorders.

Inversions of the long (q) arm of chromosome #5 are reported in five cases with hematologic disorders. Inversion of 5q with breakpoints in bands 5q13 and 5q33 was found in two cases with lymphoid malignancy and in two cases of myeloid hematologic malignancy. Because an inversion of 5q with breakpoints in 5q22 and 5q33 was also found in a case with myeloproliferative syndrome, the common denominator in these five cases was band 5q33. An extraordinary cluster of genes affecting cell growth and differentiation is present on 5q and may be altered by the chromosome rearrangement of 5q in hematologic disorders.

Adult↗

Control of cloned gene expression by promoter inversion in vivo: construction of the heat-pulse-activated att-nutL-p-att-N module.

We have constructed a prototype of gene-expression plasmids with three novel properties: its "OFF phase" is absolute in all common hosts because the expression promoter is facing away from the studied gene and is blocked by a strong terminator; the "ON phase" is attained by the rapid and efficient inversion of the promoter; only a short heat pulse or exposure to other inducing agents is required to initiate this two-stage process. In the first stage, synthesis of the phage lambda Int protein is induced by the transient derepression of the properly engineered lambda xis- cIts857 prophage. In the immediately following second stage, Int causes inversion of a promoter cloned between the inverted ----P'OP phage att site and the normally oriented ----delta PO delta P' pseudo-bacterial att site. The inverted promoter can now control the expression of the studied gene and also of the lambda N gene cloned in tandem. The N product, in conjunction with the nutL site placed downstream of the promoter, permits efficient antitermination of any terminators present in the att sites, in the plasmid or in the cloned DNA, making this system efficient and of practical value. Employing the promoter-inverting plasmid, it was possible to obtain rapid onset and a high level of galactokinase synthesis from the cloned galK gene. Only a transient, 10-min induction at 42 degrees C was employed, permitting protein synthesis at 30 degrees C, which might be of importance for thermosensitive products. Furthermore, the entire promoter-inversion module can be transferred to any plasmid as a 1.3-kb AvaI-ClaI fragment (see Fig. 1).(ABSTRACT TRUNCATED AT 250 WORDS)

Bacteriophage lambda↗

Control of cloned gene expression by promoter inversion in vivo: construction of improved vectors with a multiple cloning site and the Ptac promoter.

We have constructed three gene-expression plasmids which contain (an) invertible promoter(s) and a multiple cloning site. We used either the plac promoter or the ptac-plac tandem promoters, the latter directing a more than fourfold increase in expression of the galK reporter gene in Escherichia coli host. All these plasmids were derived from the pNH7a expression plasmid of Podhajska et al. [Gene 40 (1985) 163-168]. Like pNH7a, these vectors have three novel properties: (i) in the 'OFF phase', the promoter is facing away from the gene to be expressed, (ii) the 'ON phase' is attained by the rapid and efficient inversion of the promoter mediated by the phage lambda Int product and the flanking attP and attB sites, which have a divergent orientation, and (iii) only a short heat pulse is required for the efficient inversion of the promoter and switching from the OFF to the ON phase. As for the pNH7 a vector, the present plasmids contain the nut-N transcriptional antitermination system, which permits efficient gene expression even if terminator(s) happen to be present between the promoter(s) and the expressed gene. The promoter inversion is rapid and over 95% efficient, as assayed by restriction analysis and galactokinase assay. Many genes could be conveniently cloned in the multiple cloning site, and then either kept totally silent or expressed in a rigidly controlled manner. Moreover, the pNH8, pNH16 and pNH18 plasmids, with already inverted promoters, could be used for expression of cloned genes, either in an unregulated manner or regulated by the lac repressor. They would be particularly useful for genes associated with terminators affecting their expression.

Attachment Sites, Microbiological↗

Use of Intron 1 and 22 inversions and linkage analysis in carrier detection of hemophilia A in Indians.

BACKGROUND: Hemophilia A is an X-linked recessively inherited bleeding disorder characterized by deficiency of procoagulant factor VIII (FVIII). METHODS: Sixty unrelated hemophilia A patients and their family members have undergone tests for carrier detection by linkage analysis using the polymorphic markers Bcl I, Xba I and Intron 13 or 22 VNTRs. In families of sporadic hemophiliacs, the carrier status of female subjects was ascertained by linkage analysis along with FVIII:C/VWD Ag estimation. RESULTS: Of the 33 families with positive family history, the defective X chromosome was tracked in 28 mothers. The carrier status of females from hemophilia A families with positive family history, ascertained by linkage analysis and Intron 22 and 1 inversion, was made out in 85% cases. FVIII:C/VWF Ag ratio was evaluated in 36 females from 9 sporadic hemophilic families. Using the FVIII:C/VWF Ag ratio along with linkage analysis, carrier status was determined in 9 (25%) of the 36 females studied. Using Intron 22 inversion along with linkage analysis and FVIII:C/VWF Ag estimation, the informativity in female subjects from families of sporadic hemophiliacs increased from 25% to 52%. CONCLUSION: In the West, linkage analysis with Bcl I, Xba I and Intron 13 or 22 VNTR markers and inversion 22 offers a good tool for carrier detection of hemophilia A in India.

Chromosome Inversion↗

An inversion of 25 base pairs causes feline GM2 gangliosidosis variant.

In G(M2) gangliosidosis variant 0, a defect in the beta-subunit of lysosomal beta-N-acetylhexosaminidase (EC 3.2.1.52) causes abnormal accumulation of G(M2) ganglioside and severe neurodegeneration. Distinct feline models of G(M2) gangliosidosis variant 0 have been described in both domestic shorthair and Korat cats. In this study, we determined that the causative mutation of G(M2) gangliosidosis in the domestic shorthair cat is a 25-base-pair inversion at the extreme 3' end of the beta-subunit (HEXB) coding sequence, which introduces three amino acid substitutions at the carboxyl terminus of the protein and a translational stop that is eight amino acids premature. Cats homozygous for the 25-base-pair inversion express levels of beta-subunit mRNA approximately 190% of normal and protein levels only 10-20% of normal. Because the 25-base-pair inversion is similar to mutations in the terminal exon of human HEXB, the domestic shorthair cat should serve as an appropriate model to study the molecular pathogenesis of human G(M2) gangliosidosis variant 0 (Sandhoff disease).

Animals↗

Inversion, duplication, and changes in gene context are associated with human chromosome 18 evolution.

Human chromosome 18 differs from its homologues in the great apes by a pericentric inversion. We have identified a chimpanzee bacterial artificial chromosome that spans a region where a break is likely to have occurred in a human progenitor and have characterized the corresponding regions in both chimpanzees and humans. Interspecies sequence comparisons indicate that the ancestral break occurred between the genes ROCK1 and USP14. In humans, the inversion places ROCK1 near centromeric heterochromatin and USP14 adjacent to highly repetitive subtelomeric repeats. In addition, we provide evidence for a human segmental duplication that may have provided a mechanism for the inversion.

Animals↗

A case report of rhabdomyosarcoma of the uterus associated with uterine inversion.

BACKGROUND: Alveolar rhabdomyosarcoma is an uncommon malignant soft tissue tumor rarely found in the genital tract. This tumor is associated with a poor prognosis, especially in the adult population. Equally as rare are non-puerperal uterine inversions secondary to sarcomas. CASE: A 21-year-old obese woman was initially evaluated with excessive vaginal bleeding. On exam, a large pedunculated mass protruding from the cervix was seen and biopsy of this mass revealed an alveolar rhabdomyosarcoma. The patient was treated with adjuvant chemotherapy consisting of VAC (Vincristine, Actinomycin, and Cyclophosphamide) for a presumed cervical rhabdomyosarcoma. After five cycles of chemotherapy the patient underwent a total abdominal hysterectomy and bilateral salpingo-oophorectomy, at which time a complete uterine inversion was noted with the tumor located at the fundus of the uterus. Final pathology showed alveolar rhabdomyosarcoma of the uterus. The patient then received additional postoperative VAC regimen for a total of 10 treatments and remains in good health with no evidence of disease 20 months from diagnosis. CONCLUSION: This case report describes the only reported case of uterine inversion secondary to alveolar rhabdomyosarcoma of the uterus and discusses current therapeutic options for adults.

Adult↗

Non-puerperal uterine inversion in association with uterine sarcoma: case report in a 26-year-old and review of the literature.

INTRODUCTION: Inversion of the uterus associated with a uterine sarcoma is extremely rare with only 17 cases reported since 1887, so that its clinical presentation and appearance at laparotomy may be confusing. CASE: A 26-year-old woman presented with a vaginal mass and bleeding. At laparotomy, her uterus appeared depressed or concave. The final diagnosis of uterine sarcoma and inversion was unique in her age group. CONCLUSIONS: Uterine sarcoma with inversion can occur in the premenopausal age group. It presents as a vaginal mass with bleeding. As a clue to the diagnosis, the uterus per se may not be palpable or it may appear concave on physical exam or at laparotomy.

Adult↗