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PubMed1990

A segment of human Vh gene locus is duplicated.

In humans, the kappa light chain variable region gene (Vk) locus evolved in part by duplications of four large segments. Similarly, some portions of the human heavy chain constant region gene locus are duplicated. Recently, we found that the Humhv3005 Vh gene is highly homologous to the reported 1.9III gene. Subsequently, restriction fragment length polymorphism study of the human Vh locus with a 1.6-kb EcoR1 fragment downstream of the hv3005 gene (termed hv3005/E1.6) suggested that the hv3005 and the 1.9III Vh loci might be generated by duplication from a common-ancestor Vh gene segment. To assess this possibility, we mapped the 15-kb region of the isolated hv3005 clone, beginning from 2 kb upstream, and sequenced the adjacent Vh4 gene (designated Humhv4005) located 10 kb downstream of the hv3005 gene. The result showed that hv4005 shared 99% homology with the 1.9II gene, located about 11 kb downstream of the 1.9III gene. Taken together, these data demonstrate that the hv3005-hv4005 region and the 1.9III-1.9II region arose by a duplication of a common ancestor Vh gene segment.

Amino Acid Sequence↗
PubMed1987

Partial duplication 16q: report of two affected siblings resulting from a maternal translocation and literature review.

Two siblings with a partial duplication 16q, born to a woman with a balanced translocation (6;16), are described. The first infant died at 8 weeks of age; the second died at 4 months. Fifteen other cases of duplications involving 16q have been reported, all of them derived from a balanced parental translocation. The most frequent physical findings have included dysmorphic facies characterized by high forehead, prominent nose, antimongoloid slant, malformed ears, and micrognathia, as well as flexion contractures of the joints, deformity of the feet, and genital hypoplasia in the male. Anorectal, intestinal and cardiac malformations were less frequent findings. Most of the affected infants died at ages ranging from 8 days to 6 months. The few with longer survival (up to 6 years) had a shorter, more distal segment duplication of chromosome 16. Although intrauterine growth retardation and microcephaly were not always present at birth, most of the infants had postnatal growth failure. The phenotypic and clinical findings of the two infants in this report are compared with those of previously reported cases, from which there appears to be correlation of the length of the 16q duplication with clinical phenotype and survivals.

Abnormalities, Multiple↗
PubMed1989

An estimate on the frequency of duplicated haplotypes and silent alleles of human C4 protein polymorphism. I. Investigations in healthy Caucasoid families.

The frequency of duplicated and non-expressed C4 alleles was determined by segregation analysis in 31 German and five French families with altogether 274 individuals by submitting the complete data from C4 protein phenotyping, including C4 beta chains, and the other classical MHC markers to the family analysis programme (FAP). From 120 unrelated German haplotypes the following frequencies were derived for silent alleles: C4A*Q0 0.2000, C4B*Q0 0.2083, and for the total of homo- and heteroduplicated C4A resp. C4B alleles: C4"DA"* 0.1333, C4"DB"* 0.1000. The true occurrence of the duplicated C4A*2, "DB*21" haplotype, first observed in French families, was found to be 0.0250 in the German sample. While the frequency of duplicated C4 haplotypes confirms earlier estimates, the increase in the frequency of silent alleles corresponds to those assumed from investigations at the DNA level. The results demonstrate classical protein typing with inclusion of C4 beta chain types to be an indispensable and powerful tool for haplotype recognition; they support the hypothesis that deletion at one C4 locus is accompanied by duplication at the other in a majority of haplotypes.

Alleles↗
PubMed1996

MELAS syndrome associated with a tandem duplication in the D-loop of mitochondrial DNA.

We describe a family with two cases of adult-onset mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) syndrome. Interestingly, the proband also had non-insulin dependent diabetes mellitus and hyperthyroidism. Endocrinological studies demonstrated a high titer of TSH receptor antibody in the proband and elevated levels in her maternal relatives. Analysis of mitochondrial DNA (mtDNA) showed an A-to-G transition at nucleotide position 3243 in the tRNA (Leu(UUR)) gene (A3243G) in the three generations of the family. Furthermore, a previously described -260 bp tandem duplication in the D-loop region of mtDNA was also found in the proband and her maternal relatives. To our knowledge, such kind of duplication has never before been reported in the MELAS syndrome. The proportions of mtDNA with the -260 bp tandem duplication and A3243G point mutation were 12.5% and 82% in the muscle, respectively, and 1.6% and 35% in the blood cells, respectively, of the proband. We conclude that the hyperthyroidism in this MELAS patient may be related to the tandem duplication in the D-loop of mtDNA. This study further substantiates the importance of searching for additional genetic mutations in mitochondrial encephalomyopathic patients with new clinical phenotypes.

Adult↗
PubMed1988

Accuracy of repeated single versus averages of repeated duplicates of probing depth measurements.

The present study aims to determine to which extent averages or deepest recordings of repeated duplicates of probing depth measurements may increase the accuracy as compared to repeated single measurements. In total, 1247 sites were recorded in 8 patients with advanced periodontitis. The patients had received initial treatment. Each site was probed 4 times with time intervals of 100 min. The standard deviation of differences between repeated single measurements of 0.97 mm decreased with a factor square root of 2 to 0.69 mm for differences between averages of repeated duplicates of measurements. Differences between the averages and the deepest recordings of repeated duplicates of measurements showed a non-Gaussian distribution. This implies that the type-I error can not be computed on the basis of the standard deviation of the error with the use of parametric statistical analysis. The best estimate for the type-I error is the observed frequency of differences. The type-I error for differences of 3 mm or more between repeated single measurements decreased from 1.5% to 0.9% and 0.2%, when deepest recordings and averages of repeated duplicates of measurements, respectively, were compared.

Adult↗
PubMed1976

A stucy of duplication variables related to partial denture castings.

A series of stone duplications of a standard impression die was produced, using a proprietary duplicating material, the various batches of which had been prepared differently. Two different sized duplicating vessels were also employed. The critical dimensions of the stone reproductions were compared with those of the original die. Specimens of each batch of duplicating material were tested to determine the degree of permanent deformation produced by a fixed strain and strain in compression.

Colloids↗
PubMed1978

Duplications of histidine transport genes in Salmonella typhimurium and their use for the selection of deletion mutants.

We demonstrate that tandem duplications of the histidine transport operon can be selected by requesting elevated levels of transport activity to be present. Several strains were constructed which contain duplications heterozygotic for either hisJ, hisQ, or hisP. The size of one duplication which was analyzed in detail is about 16 genes, with one end close to the promoter site (dhuA) of the histidine transport operon and, therefore, enclosing about 12 more genes counterclockwise to this operon. Duplication-carrying strains could be utilized for the selection of deletion mutations by requiring both copies of the operon to be rendered defective simultaneously and, therefore, unable to transport into the cell an inhibitory histidine analog, alpha-hydrazino imidazole propionic acid. Over 60% (probably as high as 100%) of the alpha-hydrazino imidazole propionic acid-resistant strains arising in the selection are deletion mutants. The principle of our selection method is generally applicable and will be useful in the accumulation of deletions for mapping and fusing of genes and other purposes.

Alleles↗
PubMed1985

Novel rearrangements of herpes simplex virus DNA sequences resulting from duplication of a sequence within the unique region of the L component.

We constructed insertion mutants of herpes simplex virus type 1 that contained a duplication of DNA sequences from the BamHI-L fragment (map units 0.706 to 0.744), which is located in the unique region of the L component (UL) of the herpes simplex virus type 1 genome. The second copy of the BamHI-L sequence was inserted in inverted orientation into the viral thymidine kinase gene (map units 0.30 to 0.32), also located within UL. A significant fraction of the progeny produced by these insertion mutants had genomes with rearranged DNA sequences, presumably resulting from intramolecular or intermolecular recombination between the BamHI-L sequences at the two different genomic locations. The rearranged genomes either had an inversion of the DNA sequence flanked by the duplication or were recombinant molecules in which different regions of the genome had been duplicated and deleted. Genomic rearrangements similar to those described here have been reported previously but only for herpes simplex virus insertion mutants containing an extra copy of the repetitive a sequence. Such rearrangements have not been reported for insertion mutants that contain duplications of herpes simplex virus DNA sequences from largely unique regions of the genome. The implications of these results are discussed.

Base Sequence↗
PubMed1989

Short, duplicated sequence indicative of the recombinogenicity of the junction between a unique and an inverted repeat sequence in the S component of the herpes simplex virus type 1 genome.

A herpes simplex virus type 1 (HSV-1) strain, B3, was found to have a short duplication on the left junction between the unique sequence (US) and the inverted repeat sequence (RS) in the S component of the genome DNA. A short region of RS contiguous to the left US-RS junction was duplicated in B3. Based on the nucleotide sequences in and around the US-RS junctions of B3 and other HSV-1 strains, a concept of junction stretch was proposed. The organization of junction stretch is RS side 5'-(G or A stretch)AGC-3' US side. Introduction of the concept of junction stretch led to a definition of the structure in and around the US-RS junction, in the form common to HSV-1 strains. The right end of US in the HSV-1 genome was the A of the ATG initiation codon of gene US12, and thus the ATG triplet may act as a buffer to prevent expansion of RS, as is the case with HSV-2. The duplication in B3 was generated by a crossover event between a point on RS and the US side end of the left junction stretch. These observations suggest that the US side end of the junction stretch possesses the property of recombinogenicity, responsible for generation of the duplication in strain B3 and also for the formation of the US-RS junction of HSV.

Animals↗
PubMed2003

Human papillomavirus type 16 E7 oncoprotein can induce abnormal centrosome duplication through a mechanism independent of inactivation of retinoblastoma protein family members.

The human papillomavirus type 16 (HPV-16) E7 oncoprotein rapidly induces centrosome duplication errors in primary human cells, thereby increasing the propensity for multipolar mitoses, which can lead to chromosome missegregation and aneuploidy. We analyzed a series of HPV-16 E7 mutants and demonstrate that this biological activity of the E7 oncoprotein is mediated by sequences encompassing the core pRB binding site but is independent of its ability to inactivate the retinoblastoma tumor suppressor protein pRB and the related pocket proteins p107 and p130. In addition, interaction of E7 with the S4 subunit of the 26S proteasome and dysregulation of cdc25A transcription are also dispensable for the induction of centrosome duplication errors. Consistent with these results, expression of HPV-16 E7 induces abnormal centrosome duplication in a cell line that lacks functional pRB and in mouse embryo fibroblasts that are deficient for pRB, p107, and p130. These results demonstrate that the molecular mechanism whereby HPV-16 E7 induces centrosome duplication errors is independent of its ability to inactivate pRB, p107, and p130 or to interact with the S4 proteasome subunit.

Animals↗
PubMed1981

Duplicate sources of pulmonary blood supply in pulmonary atresia with ventricular septal defect.

In pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries, there is a tendency for each collateral artery to be the sole supply to a particular region of lung. On injection into a collateral artery, however, "wash-out" of contrast medium by non-opacified blood from a second source is sometimes seen. Alternatively, contrast medium may faintly "wash-in" to an adjacent lobar artery supplied from a second source. "Wash-in" and "wash-out" therefore show that a duplicate blood supply exists. To assess the importance of these phenomena, we reviewed the angiograms of 50 patients with this condition. Duplicate pulmonary blood supply not resulting from surgical shunts was found in 25 patients (50%), and in 24 of 37 patients (65%) who had selective collateral injections. In one patient two collaterals anastomosed with each other. Thirty-nine instances of duplicate supply occurred in the remaining 24. The duplicate connection was to a region of lung connected to a central pulmonary artery in 29 of 39 instances (74%). Determination of how much of the peripheral pulmonary vasculature is connected to central pulmonary arteries greatly affects decisions about palliative and corrective surgery. These results show that unless "wash-in" and "wash-out" are specifically looked for, the information obtained from angiography may be erroneous.

Aorta↗
PubMed2004

Adenocarcinoma arising from a gastric duplication cyst with invasion to the stomach: a case report with literature review.

This report describes a rare case of adenocarcinoma arising from a gastric duplication cyst, with invasion to the stomach wall, in a 40 year old Japanese man. A cystic lesion was found between the stomach and the spleen. The cyst had a well circumscribed smooth muscle layer, corresponding to the muscularis propria of the stomach and the mucosa of the alimentary tract. A well differentiated adenocarcinoma was found within the duplication cyst, invading its serosa. Well differentiated adenocarcinoma was independently found in the fundus of the stomach; the tumour of the cyst was connected by fibrous tissue. Microscopically, there was neither adenocarcinoma in situ nor precancerous lesions, such as epithelial dysplasia, suggesting that the carcinoma derived from a gastric duplication cyst that invaded the stomach. Duplication cysts should be included in the differential diagnosis of cystic masses of the gastrointestinal tract, and the possibility of malignancy within these cysts should be considered.

Adenocarcinoma↗
PubMed1988

Should we still be doing duplicate immunoassays?

To determine whether, with improvements in radioimmunoassay techniques, duplication is still necessary, the differences between duplicate results for a range of assays done routinely over one month were examined retrospectively. Differences over 10% between duplicates were found in 104/779 (13%) of assays for thyroid stimulating hormone, 27/180 (15%) for total thyroxine, 44/378 (12%) for cortisol, 15/355 (4%) for follicular stimulating hormone, 20/356 (6%) for luteinising hormone, and none for alpha fetoprotein (0/256). In only two of 779 patients (0.26%) would the different result of a pair of thyroid stimulating hormone duplicates have led to different courses of action by the laboratory. None of the other differences in any assay would have resulted in a potential misclassification. Although replication of assays will give more correct results by pure scientific criteria, the improvement is rarely clinically important and the financial cost is considerable.

Follicle Stimulating Hormone↗
PubMed1993

Mosaicism for duplication 12q (12q13-->q24.2) in a dysmorphic male infant.

We report the clinical findings in a boy with mosaicism for a duplication of chromosome 12q13.1-->q24.2. His clinical characteristics are very similar to previously reported mosaic duplications of the distal long arm of 12, as well as several cases with non-mosaic duplications. It is proposed that this represents a clinically distinguishable syndrome for 12q duplication, in mosaic or non-mosaic form.

Abnormalities, Multiple↗
PubMed1995

Inheritance of CMT1A duplication from a mosaic father.

We describe a case with molecular duplication of chromosome 17 (p11.2-p12) whose duplicated chromosome was inherited from a mosaic father. The patient has clinical manifestations consistent with Charcot-Marie-Tooth disease type 1A (CMT1A), while the mosaic father has minimal findings of CMT1A. The father was found to be homozygous with DNA markers VAW409R3A (D17S122) and p132G8RI (PMP-22) which are duplicated in CMT1A cases. Fluorescence in situ hybridisation (FISH) analysis with YAC clone 49H7 confirmed the duplication in the affected patient and diagnosed the mosaicism in his father. These findings based on clinical diagnosis and FISH analysis suggest that the mosaicism may have occurred early in embryogenesis leading to the disease in the father. This is the only reported case of CMT1A with transmission from a mildly affected mosaic father.

Blotting, Southern↗
PubMed1998

Chromosome specific comparative genome hybridisation for determining the origin of intrachromosomal duplications.

Chromosome specific comparative genome hybridisation (CGH) is a novel approach for the detection of cytogenetic abnormalities. It combines flow sorting of chromosomes, degenerate oligonucleotide primed (DOP)-PCR and a modified comparative genome hybridisation (CGH) technique to define the site and extent of intrachromosomal duplications. Chromosome specific paint probes for aberrant chromosomes and their normal homologues from four subjects with unbalanced duplications within chromosomes 2p11-15, 3q25-26, 5q34-qter, and 12q23-24.2 were made. They were then cohybridised on normal metaphase spreads and the ratio of their relative intensities of hybridisation analysed. The results were compared to those of similar experiments where regular CGH was performed on the same four patients. We provide evidence that this method can detect duplications and deficiencies which might be missed by conventional CGH, as the ratio of hybridisation of abnormal/normal DNA is 2:1 rather than 3:2. It is the method of choice where mosaicism is present or where only one of several homologous chromosomes is duplicated. Furthermore, it suggests that DOP-PCR amplifies all or most of the euchromatic regions of the genome equally.

Chromosome Aberrations↗
PubMed1998

The mechanisms involved in formation of deletions and duplications of 15q11-q13.

Haplotype analysis was undertaken in 20 cases of 15q11-q13 deletion associated with Prader-Willi syndrome (PWS) or Angelman syndrome (AS) to determine if these deletions arose through unequal meiotic crossing over between homologous chromosomes. Of these, six cases of PWS and three of AS were informative for markers on both sides of the deletion. For four of six cases of paternal 15q11-q13 deletion (PWS), markers on both sides of the deletion breakpoints were inferred to be of the same grandparental origin, implying an intrachromosomal origin of the deletion. Although the remaining two PWS cases showed evidence of crossing over between markers flanking the deletion, this was not more frequent than expected by chance given the genetic distance between proximal and distal markers. It is therefore possible that all PWS deletions were intrachromosomal in origin with the deletion event occurring after normal meiosis I recombination. Alternatively, both sister chromatid and homologous chromosome unequal exchange during meiosis may contribute to these deletions. In contrast, all three cases of maternal 15q11-q13 deletion (AS) were associated with crossing over between flanking markers, which suggests significantly more recombination than expected by chance (p = 0.002). Therefore, there appears to be more than one mechanism which may lead to PWS/AS deletions or the resolution of recombination intermediates may differ depending on the parental origin of the deletion. Furthermore, 13 of 15 cases of 15q11-q13 duplication, triplication, or inversion duplication had a distal duplication breakpoint which differed from the common distal deletion breakpoint. The presence of at least four distal breakpoint sites in duplications indicates that the mechanisms of rearrangement may be complex and multiple repeat sequences may be involved.

Angelman Syndrome↗
PubMed1980

Calcification associated with duodenal duplications in children.

Calcification of intestinal duplications is rare, and it is most uncommon in duodenal duplications. In this report, two cases illustrate distinct forms of calcification associated with duodenal duplication cysts. Each type may be confused with calcifications in other benign or malignant lesions. Calcified duodenal duplication cysts should be considered when investigating spherical upper abdominal calcifications.

Calcinosis↗