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1.
A familial reciprocal translocation, established by R-banding as t(9;13) (9p23;13q21), is described in a phenotypically normal male carrier, whose father is also a balanced carrier and wife had four consecutive spontaneous abortions. The role of translocation in reproductive failure through production of chromosomally unbalanced gametes or by impairment of the spermatogenesis is briefly discussed.  相似文献   

2.
A new case of translocation between chromosomes No. 5 and No. 12 is described. The translocation t(5;12) (5q15;12p13) is apparently balanced and was found in a child aged 3 1/2 years who was affected with severe psychomotor retardation. On the basis of the clinical picture it is suggested that the phenotype could be not dependent on the chromosomal alteration.  相似文献   

3.
An aneuploid fetus was detected prenatally by cordocentesis at 27 weeks' gestation following ultrasonographic diagnosis of severe fetal growth retardation and a large diaphragmatic hernia. The fetal karyotype was revealed to be 47,XX,der(22)t(11;22)(q23.3;q11.2) after parental bloods confirmed a balanced reciprocal translocation in the mother. Approximately 85 cases with an unbalanced karyotype 47,XX(or XY),+der(22),t(11;22) due to 3:1 meiotic disjunction in the parental translocation carrier have been reported in the world literature and only one of them was diagnosed prenatally. This is the first detailed case report of a supernumerary derivative (22) chromosome abnormality diagnosed prenatally in association with diaphragmatic hernia.  相似文献   

4.
Although the majority of patients with Beckwith-Wiedemann syndrome (BWS) have a normal karyotype, the study of those rare patients with a cytogenetic abnormality has given considerable insight into the genetics of this condition. The karyotypic abnormalities found include partial chromosome duplications of paternal origin and maternally derived translocations which usually involve the 11p15 region and provide one of the lines of evidence for the location of the BWS gene(s). Because the extent of the duplicated region in these patients is variable, the phenotypic expression of BWS is presumably due to the presence of a common duplicated region. Two unrelated patients with BWS were both noted to have a similar unbalanced t(5;11)(p15;p14) translocation. The parents in both families were unaffected but both fathers carried a balanced translocation involving the same chromosomes. Since the extent and nature of the duplication apparently determines the complex phenotypes seen in these patients, we undertook a detailed analysis of the extent of the triplicated region using fluorescent in situ hybrisation (FISH). Despite having markedly different phenotypes and presenting in disimilar ways the two patients had apparently identical duplication breakpoints.  相似文献   

5.
Meiotic segregation, recombination, and aneuploidy was assessed for sperm from a t(1;10)(p22.1;q22.3) reciprocal translocation carrier, by use of two multicolor FISH methods. The first method utilized three DNA probes (a telomeric and a centromeric probe on chromosome 1 plus a centromeric probe on chromosome 10) to analyze segregation patterns, in sperm, of the chromosomes involved in the translocation. The aggregate frequency of sperm products from alternate and adjacent I segregation was 90.5%, and the total frequency of normal and chromosomally balanced sperm was 48.1%. The frequencies of sperm products from adjacent II segregation and from 3:1 segregation were 4.9% and 3.9%, respectively. Reciprocal sperm products from adjacent I segregation deviated significantly from the expected 1:1 ratio (P < .0001). Our assay allowed us to evaluate recombination events in the interstitial segments at adjacent II segregation. The frequencies of sperm products resulting from interstitial recombination in chromosome 10 were significantly higher than those resulting from interstitial recombination in chromosome 1 (P < .006). No evidence of an interchromosomal effect on aneuploidy was found by use of a second FISH method that simultaneously utilized four chromosome-specific DNA probes to quantify the frequencies of aneuploid sperm for chromosomes X, Y, 18, and 21. However, a significant higher frequency of diploid sperm was detected in the translocation carrier than was detected in chromosomally normal and healthy controls. This study illustrates the advantages of multicolor FISH for assessment of the reproductive risk associated with translocation carriers and for investigation of the mechanisms of meiotic segregation of chromosomes.  相似文献   

6.
7.
We have identified a new dermatofibrosarcoma protuberans (DP) case with a t(17;22) (q22;q13) occurring in a child. The translocation was substantiated by the presence of one or two copies of the sole der(22)t(17;22). This rearrangement added to two normal chromosomes 17 and one or two chromosomes 22, resulted in trisomy 22cen-q13 and trisomy (or tetrasomy) 17q22-25. This observation confirms the specificity of the association of DP with the t(17;22) found together with extra copies of the der(22)t(17;22). It also points out a possible prevalence of translocation rather than rings in DP of the childhood disease.  相似文献   

8.
The prenatal diagnosis of an 11q;22q translocation in a triplet pregnancy detected at the time of chorionic villus sampling (CVS) because of advanced maternal age is reported. Karyotypes obtained from two apparently different CV samples showed the balanced form of translocation, while the one obtained from a third empty sac showed the unbalanced form: 46,XX,-22,+der(22)t(11;22). Second-trimester amniocentesis confirmed the balanced translocation in one of the two viable fetuses and a normal karyotype in the other. The detected karyotypes derived from two different types of meiotic segregation, alternate and adjacent 1. To our knowledge, this is the first reported case of an unbalanced karyotype not due to a 3:1 meiotic segregation of this specific translocation.  相似文献   

9.
The t(11;22) (q23;q11) translocation is the most frequently identified familial reciprocal translocation in humans. In translocation carriers, 3:1 meiotic segregation with tertiary trisomy can occur resulting in abnormal progeny with the der(22) as the supernumary chromosome. Affected children have a distinct phenotype with multiple anomalies and severe mental retardation. We have identified a child with developmental delay and multiple anomalies consistent with the der(22) phenotype. Cytogenetic analysis showed an abnormal chromosome complement of 47,XX,+der(22)t(11;22)(q23; q11) in all 50 cells analysed. FISH analysis using chromosome 11 and 22 painting probes showed a pattern consistent with a reciprocal translocation of the distal bands 11q23 and 22q11 respectively. Parental karyotypes were normal. RFLP analysis of locus D22S43, which maps above the t(11;22) breakpoint, showed that the der(22) was paternal in origin and indicated that the normal chromosomes 22 were the probable result of maternal heterodisomy. RFLP analysis of locus D22S94, which maps below the t(11;22) breakpoint, also suggested that both normal chromosomes 22 of the child represented the two maternal homologues. Non-paternity was excluded through the analysis of 10 microsatellite markers distributed on 10 different chromosomes and three VNTRs on three different chromosomes. To the best of our knowledge, this is the first reported case of a patient with an abnormal karyotype resulting from a de novo translocation in the paternal germline with probable unbalanced adjacent 1 segregation and maternal non-disjunction of chromosome 22 in meiosis I.  相似文献   

10.
Molecular cytogenetic analyses have resolved the pathogenetic aberration of an 8-year-old girl with tricho-rhino-phalangeal syndrome type I (TRPS I), normal intelligence, and a karyotype originally described as 46,XX,t(8;13)(q24;q21). R- and Q-banding and high resolution R-banding analyses have also disclosed a seemingly mosaic abnormality of the distal short arm of chromosome 7 but have not fully characterized this abnormality. Combined primed in situ labelling and chromosome painting, and three-colour chromosome painting have revealed a complex, apparently balanced translocation t(7;13;8). Fluorescence in situ hybridization with yeast artificial chromosome and cosmid clones from 8q24.1 has shown an interstitial deletion of at least 3 Mb covering most of the TRPS I critical region.  相似文献   

11.
OBJECTIVE: To determine if a correlation exists between the level of maternal serum alpha-fetoprotein (MSAFP) elevation and the rate of adverse pregnancy outcome, to examine the timing of pregnancies ending in fetal or neonatal death, and to develop a protocol for antepartum surveillance in an effort to prevent these adverse outcomes. STUDY DESIGN: Singleton pregnancies with a single second-trimester elevated MSAFP > or = 2.0 multiples of the median (MoM) were eligible if a targeted ultrasound evaluation (< 24 weeks) was in agreement with the dates and no fetoplacental anomaly was detected. Three groups were established based on the second-trimester MSAFP elevation: 2.0-2.49, 2.5-2.99 and > or = 3.0 MoM. RESULTS: Among the 383 patients enrolled, delivery data were available on 333 infants. Stratified by MSAFP elevations of 2.0-2.49, 2.5-2.99 and > or = 3.0 MoM, the rates of adverse pregnancy outcome were: (1) preterm birth: 14.3%, 15.6%, 20.3%; (2) small for gestational age at birth: 7.4%, 11.1%, 22.2%; and (3) perinatal deaths (neonatal and fetal): 2.6%, 3.3%, 5.6%. Seven pregnancy losses (three neonatal and four fetal deaths) occurred prior to 28 weeks. Of these seven, six fetuses exhibited intrauterine growth retardation by 23-26 weeks' gestation, and five of six were associated with MSAFP levels > or = 2.5 MoM. Four losses (two neonatal and two fetal deaths) occurred after 28 weeks. Of these, three involved structurally normal infants with normal growth who died after 34 weeks. All three of these pregnancies exhibited MSAFP elevations < 2.5 MoM. CONCLUSION: In pregnancies with an unexplained elevated second-trimester MSAFP, the rate of adverse pregnancy outcomes is increased with higher elevations. Any proposed program to improve pregnancy outcome in patients with unexplained MSAFP elevations must include efforts aimed at preventing preterm delivery, repeat ultrasound at 24-26 weeks to rule out early-onset intrauterine growth retardation in pregnancies with elevations > or = 2.5 MoM and fetal biophysical monitoring, even in normally grown fetuses, instituted at 32 weeks to detect fetuses at risk for intrauterine death.  相似文献   

12.
We describe two cases of non-Hodgkin's lymphoma associated with t(3;6)(q27;p21.3) and BCL6 rearrangement. The first case was in a 78-year old woman, whose performance status (PS) was 1, the serum lactate dehydrogenase (LDH) level was elevated, and the Ann Arbor stage was IIIA with no extra nodal lymphomatous site. The pathological diagnosis from a biopsy of the inguinal lymph node was 'malignant lymphoma (ML), follicular, small cleaved' according to the Working Formulation. Complete remission was achieved. Although she had relapse in 1992, remission was obtained again. The second case was in a 62-year old man, whose PS was 1, the serum LDH was normal, and Ann Arbor stage was IVA with the involvement of the small intestine. Histological diagnosis of the cervical lymph node was 'ML, diffuse, large cell'. Complete remission was obtained without relapse. The 3q27 translocations, found in 20-30% of non-Hodgkin's lymphoma, are unique in having multiple chromosomal translocation partners. Chromosome band 6p21.3 is one of these partner sites that may be the site of a novel gene. The two cases presented here show that this translocation is a non-random chromosomal change involving 3q27 and BCL6. Since t(3;6) was the sole karyotypic abnormality in one case, this translocation may play a role in lymphomagenesis.  相似文献   

13.
Cytogenetic analysis of a bone marrow aspirate from a patient with acute lymphoblastic leukemia (ALL) revealed the presence of a complex karyotype containing the translocation, t(14;18)(q32;q21). Further investigations using fluorescence in situ hybridization (FISH) allowed the characterization of an additional translocation, t(8;9)(q24;p1?). The association of t(14;18)(q32;q21) and t(8;9)(q24;p13) has recently been described in two patients with de novo ALL (Nacheva et al. Blood 1993;82:231-240) and this report supports these findings.  相似文献   

14.
A translocation between the long arms of chromosomes 11 and 22, t(11;22)(q23;q11), is the most frequent constitutional reciprocal translocation in man. This chromosome abnormality has not previously been reported to be associated with an increased risk for neoplasia. The observation of one patient with a constitutional translocation t(11q;22q) and breast cancer prompted us to study the relationship between these two conditions. The incidence of breast cancer was determined in carriers of t(11q;22q). The karyotypes were determined by QFQ-banding, and the breakpoints were then further characterized by fluorescent in situ hybridization. Eight families with a total of 22 balanced carriers were found. In five of these families there was one case of breast cancer each. In another family a case of an unknown malignancy was reported in one member. No other malignancies were found among these patients. The number of breast cancer cases was significantly higher than expected among the translocation carriers (P < .001). The chromosomal breakpoints showed the same localization with the markers used, in the seven families studied. The association of constitutional translocation t(11q;22q) and breast cancer identifies a subset of patients with a highly increased risk for breast cancer who would benefit from counseling and screening. It also suggests the involvement of genes on 11q and/or 22q, in the tumorigenesis of breast cancer.  相似文献   

15.
We report on a familial three way translocation involving chromosomes 3, 6, and 15 identified by prometaphase banding and fluorescence in situ hybridisation (FISH). Two mentally retarded sibs with different phenotypic abnormalities, their phenotypically normal sister and mother, and two fetuses of the phenotypically normal sister were analysed. The terminal regions of chromosomes 3q, 6q, and 15q were involved in a reciprocal translocation, in addition to a paracentric inversion of the derivative chromosome 15. Conventional cytogenetic studies with high resolution GTG banding did not resolve this rearrangement. FISH using whole chromosome paints (WCPs) identified the chromosomal regions involved, except the aberrant region of 3q, which was undetectable with these probes. Investigation of this region with the subtelomeric FISH probe D3S1445/D3S1446 showed a balanced karyotype, 46,XX,t(3;15;6) (q29;q26.1;q26), inv der(15) (q15.1q26.1) in two adult females and one fetus. It was unbalanced in two sibs, showing two different types of unbalanced translocation resulting in partial trisomy 3q in combination with partial monosomy 6q in one patient and partial trisomy 15q with partial monosomy 6q in the other patient and one fetus. These represent apparently new chromosomal phenotypes.  相似文献   

16.
Chromosome translocation of t(14;18) can be detected in most cases of centroblastic/centrocytic follicular lymphomas. They are causative factors of lymphomas but the translocation is present in different other types of diseases although the translocation does not belong to the features of these illnesses. Our present work shows the appearance of t(14;18) translocation in lymphocytes of two patients of Sj?gren's syndrome, one that of Whipple disease as well as one of healthy donors' lymphocytes using polymerase chain reaction technique presented in one of our previous publication. The translocation occurred in the mbr of bcl-2 gene in all cases showed and the bcl-2 gene was coupled with the immunoglobulin heavy chain gene. These results are definitively positive concerning the fact of translocation as it has been proved by sequencing of the amplification products showed in our earlier and present paper. Because relatively high percentages of Sj?gren's syndrome patients develop later on lymphoma, the early detection of the translocation could result in a more successful diagnosis as well as treatment of the disease. The question arises, however, what role the translocation plays in illnesses such as the Whipple disease or what kind of consequences can be drawn from the appearance of the t(14;18) translocation in lymphocytes of healthy donors.  相似文献   

17.
18.
Preimplantation genetic diagnosis of translocations can be performed on first polar bodies (PB) at metaphase stage using FISH with whole-chromosome painting DNA probes. Here we report the use of this method in a couple in which the female was a carrier of a balanced translocation 46,XX,t(11;16)(q21;q22). This case unusual in that two polar bodies showed recombination events between the homologue chromosomes of 11 and 16 pairs, resulting in M-II oocytes with monovalent chromosomes having a normal and a derivative chromatid. For this type of case, PGD analysis on polar bodies cannot give a useful result, because, at the second meiotic division, either of these chromatids could remain in the oocyte, resulting in a normal, balanced or unbalanced embryo. PGD analysis on blastomeres can provide a solution. 11 previous cases of PGD of translocations performed by metaphase PB analysis are reviewed.  相似文献   

19.
Five women suffering from hyperandrogenism due to adrenal enzyme deficiency, with various clinical symptoms and discovered at a more or less early stage, had a total of 7 pregnancies. 21-hydroxylase was deficient in three, and 11-beta-hydroxylase in two women. The pregnancies occured 6 months to 10 years after corticosteroid treatment was started in four cases, and after it was discontinued in a case of partial deficiency in 11-beta-hydroxylase. Four women delivered on term, two of them normally and two by caesarean section. The fifth woman delivered prematurely on the 33rd week. Two pregnancies were interrupted either spontaneously or voluntarily. None of the newborn babies (three girls and two boys) showed any abnormality. With the exception of the premature girl, their weight was normal. The oldest of the girls had a normal puberty at the age of thirteen.  相似文献   

20.
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