Indophenol-oxidase in patients with Down's syndrome due to simple trisomy and to translocation 21/22

Summary The indophenol-oxidase of erythrocytes was studied in three groups (trisomy G 21, unbalanced translocation 21/22, and control group). The increase of IPO activity in patients with trisomy G 21 was observed, whereas in those with unbalanced translocation 21/22 the levels of IPO were slightly lower than in control group.     

Familial translocation t(1p-;21q+) associated with Down's syndrome

Summary Familial occurrence of 1/21 translocation in connection with trisomy 21 was described. The possibilities of inheritance of further chromosome rearrangements arising during the gametogenesis of persons with this translocation were considered.     

46,XX,t(15;21)/47,XX,15p-,+21 mosaicism in a child with Down's syndrome

We report here the first case of a mosaic Down's syndrome in which both clones are trisomic for chromosome 21, one of them (90%) by a Robertsonian translocation (15;21) appearing de novo, and the other (10%) by an additional chromosome 21. Three hypotheses can explain the appearance of such a mosaic: that of a chimera formed by the fusion of two trisomy 21 zygotes, one of which had a Robertsonian translocation, the other an additional trisomy 21 zygote; that of a fusion between a chromosome 15 and a chromosome 21 in one of the early segmentation blastomeres of a trisomy 21 zygote; the more probable hypothesis of the occurrence of a fission at the break-attachment point of a Robertsonian translocation (15;21) in one of the cells arising from the early postzygotic divisions of a zygote which was a trisomy 21 by Robertsonian translocation (15;21).     

Patial trisomy 1 due to 1/17 translocation in Ph'-Positive chronic myelocytic leukemia

Summary A patient with chronic myelocytic leukaemia (CML) had the Philadelphia chromosome from the standard 9/22 translocation, a partial trisomy 1 secondary to an unbalanced 1/17 translocation, and a more recent clone with the addition of trisomy 22. This is the third case of partial trisomy 1 associated with the Philadelphia chromosome. Trisomy 1 in haematological disorders is discussed with reference to its clinical significance in CML, the segment of chromosome no. 1 involved, and the mechanisms of origin of the partial trisomies. Anomalies of chromosome 1, although not specific to any of them, seem to be important in the development of myeloproliferative disorders and of neoplasms in general.     

Karyotype peculiarities of malignant lymphomas

Summary Karyotypes of 30 malignant lymphomas were studied with the aid of G-banding. Frequent occurrence of rearranged chromosomes 14 and 11 was noted. In several tumors, identical acrocentric markers, appearing after translocation of the long arm of chromosome 11 on the long arm of chromosome 14, were revealed. Other common karyotype abnormalities in lymphomas were trisomy 3 and trisomy 18. The chromosomes preferentially involved in karyotype abnormalities of the malignant lymphomas are mostly not altered in other hemoblastoses.     

Chromosome studies in 500 induced abortions.

A survey of the chromosome constitution in 500 induced abortions (5-12 menstrual weeks) was undertaken over a period of 1 1/2 years. There were 34 cases (6.8%) of gross chromosome anomalies: 2 cases of trisomy A; 5 of trisomy C (including XXX and XXY); 1 of mosaic trisomy C; 4 of trisomy D; 2 of trisomy E; 2 of trisomy G; 1 of double trisomy E and G; 1 of XYY; 4 of monosmy C (including XO); 2 of mosaic monosomy C; 1 of mosaicism of ring D chromosome; 1 of extra small metacentric chromosome; 3 of triploidy (including triploidy with double trisomy C and G); and 5 of tetraploidy and its mosaicism. An increased risk for the occurrence of trisomic anomalies was found with advancing age of the mothers. In contrast, the production of monosomies was not age-related. Trisomies were the most common type of anomalies and were found almost at random, regardless of the characteristics of chromosomes. Neither satellited nor small chromosomes were predominantly involved in the formation of chromosome anomalies.     

Genetics of partial trisomies. I. Trisomy 2q

The family, where 2 children had partial trisomy 2q33-q ter, due to paternal translocation t(2;18) (q33;p11.1), was examined. The analysis of 36 cases of trisomy 2q showed that the forms connected with parental chromosomal rearrangement prevailed in the genesis of trisomy 2q. Moreover, the balanced carrier-mothers were more common than fathers. The 2q34-q ter segment may be considered "critical" for occurrence of trisomy 2q syndrome. In case of equal triplication, the similarity between the patients within the same family is greater than between those from different families. The value of intragroup similarity between the patients with equal trisomies may be used for evaluation of phenotypical similarity at different triplicated segments.     

Familial trisomy 20p five cases and two carriers in three generations a review.

A clinically normal mother of three retarded children has been determined by G-banding to have a balanced translocation 46,XX,t(13;20) (q34;p11.2). The children each have an unbalanced form of the translocation with partial trisomy for 20p. Extensive gene marker studies have been unable to affix any specific gene locus onto the short arm of chromosome 20. The balanced translocation was inherited from the maternal grandfather. Two phenotypically abnormal deceased members of the family are believed to have had the unbalanced trisomy 20p condition. An increases number of spontaneous abortions were possibly due to lethal unbalanced 20p deletions. The moderate to mild mental retardation and somewhate unusual features (round face, prominent cheeks and nose, short mandible) in the three siblings and two other affected relatives suggest that trisomy of the short arm of chromosome 20 may cause a distinguishable clinical syndrome. Vertebral abnormalities and abnormal dermatoglyphics are part of the picture. Clinical and cytogenetic findings of all reported cases are compared.     

Tertiary trisomy of 10p15.pter and 14pter.ql3 due to maternal translocation t(10;14)(p15;q13)

Double partial trisomy resulting from 3:1 segregation of the respective chromosomal segments of the chromosomes involved in a balanced translocation in meiosis is rarely reported in the literature. We present here a first patient with multiple congenital malformations associated with double partial trisomy of 10pter-p15 and 14pter-q13 resulting from 3:1 segregation of maternal balanced translocation t(10;14)(p15;q13). Proximal partial trisomy of chromosome 14 and subterminal trisomy of the short arm of the chromosome 10 are rare. The present case is the first case with double partial trisomy of these segments resulting from 3:1 segregation of a maternal balanced translocation.     

Partial trisomy 18q11.2-->qter due to de novo unbalanced translocation of chromosomes 15 and 18 analyzed by fluorescence in situ hybridization

This report presents a case with partial trisomy 18q resulting from de novo unbalanced translocation of chromosomes 15 and 18 displaying the features of pure trisomy. This is the first reported case with partial trisomy 18q due to unbalanced translocation between chromosomes 15 and 18. Clinical findings of our case have been compared with the reported cases' had partial trisomy 18q and the importance to recognize the cases with chromosome abnormalities to give genetic counseling and prenatal diagnosis for subsequent pregnancies has emphasized.     

A case with laryngeal atresia and partial trisomy 9 due to maternal 9;16 translocation.

A newborn with a partial trisomy 9 and a partial trisomy 16q is described. The child died shortly after birth because of laryngeal atresia. The chromosome anomaly was the result of a 3:1 segregation of a maternal translocation t(9;16) (q22;q24). The pertinent literature on both partial trisomy 9 and partial trisomy 16q is reviewed. All cases with partial trisomy 9 were either de novo or the result of a maternal translocation, possibly indicating the influence of imprinting on this chromosomal abnormality. The relationship between the laryngeal atresia and other features in the patient and the chromosome anomalies remains uncertain.     

Prenatal cytogenetic analysis of women with high risk for genetic disorders

165 prenatal cytogenetic analyses are reported. The culture and Giemsa or quinacrine mustard (QM) staining processes are described. Karyotypes from both Giemsa and QM metaphases were analyzed. The main indications for amniocentesis were: 1)previous child with Down's syndrome (65), 2)advanced maternal age (74), 3)D/G carrier (5), 4)Duchenne muscular dystrophy (5) or 6)previous indication of other chromosomal anomaly. In the advanced maternal age group, 4 G21 and 1 E18 trisomy fetuses were detected. No chromosomal abnormalities were seen in the group referred for a previous child with Down's syndrome, although one woman was found to have a 9/13 translocation herself. Another woman with 13/14 translocation gave birth to a healthy boy with a 13/14 translocation, as predicted. Of 5 women referred for D/G translocation carriers, 1 had a fetus with a 46, X,Y,-D + t(DqGq) karyotype. Sex determination for X-linked anomalies resulted in detection of 2 Duchenne's muscular dystrophy, 1 hemophilia, 1 Norrie's syndrome, and 1 Pelizaeus-Merzbacher's syndrome.     

Partial trisomy 18(q11 leads to qter) in an infant and aborted fetus resulting from a balanced paternal translocation t(13;18)(q32:q11).

Partial trisomy 18 is described in a two month old female with severe mental, motor and growth retardation, associated with multiple congenital anomalies characteristic of complete trisomy 18. Trisomy for almost all of 18q resulted from adjacent I segregation of a paternally inherited translocation t(13; 18)(q32:q11). The balanced translocation was observed in three generations of the family. Partial trisomy 18q identical to that observed in the proband was found in a subsequent miscarriage.     

Familial Down syndrome due to t(10;21) translocation: evidence that the Down phenotype is related to trisomy of a specific segment of chromosome 21.

This report deals with a reciprocal t(10;21) translocation which is observed in three generations of a family. Included are examples of the balanced translocation, adjacent-2 segregation producing three patients with trisomy of the distal long arm of chromosome 21 and the Down syndrome, and 3-1 disjunction producing trisomy of the proximal segment of chromosome 21 in a mildly mentally retarded boy without phenotypic features of the Down syndrome. These data provide evidence that the Down phenotype is attributable to trisomy of the distal long arm of chromosome 21.     

Exclusion gene mapping utilizing patients with chromosome imbalance: the HL-A system as a prototype.

17 chromosomally unbalanced patients, their siblings and parents were tested for HL-A types and for up to 25 other polymorphic systems to determine whether there was gain or loss of an allele concurrent with the gain or loss of chromosome material. 5 patients had trisomy of part or all of a chromosome; 2 had trisomy of a segment and also deletion of chromosome material. All 7 were due to a familial translocation. The remaining patients had small deletions; 5 had ring chromosomes, 4 had rod deletions and 1 had missing chromosome material due to a heritable translocation. All cases were informative at the HL-A loci because of the high degree of polymorphism of the system whereas only some of the other systems were informative. None of the 17 patients showed unusual inheritance of HL-A or any other of the polymorphic systems examined. These results provide evidence excluding the HL-A and other loci from a number of possible locations in the human genome.     

Trisomy 16q21»qter

Summary A case of trisomy 16q secondary to a paternal 16/18 translocation is described. A comparison of this case with the few other cases of trisomy 16q described in the literature indicates that trisomy for the long arm of chromosome 16 results in a severely affected phenotype and early death. Conversely, patient with trisomy 16p do not have gross abnormalities. We postulate that the prenatal lethality of full trisomy 16 is mainly due to the trisomy for the long arm.     

Autosomal Trisomies and Partial Trisomy Syndromes: (With Presentation of Two Cases of Partial Trisomy for the E Group of Chromosomes)

The establishing of 46 chromosomes as the normal complement in man and the report of the sex chromatin bodies in buccal smears were followed by reports of trisomies and other abnormal patterns of the X and Y chromosomes in Klinefelter''s and Turner''s syndromes. Abnormal autosomal complements were described in mongolism, in the E-trisomy syndrome, the D-trisomy syndrome, in the Sturge-Weber syndrome, Waldenstrom''s macroglobulinemia, benign congenital hypotonia, atrial septal defect and in the schizoid personality. Certain of these conditions, as well as the “oral-facial-digital” syndrome, were also found to exist as partial trisomies. The mechanism of a trisomy is one of non-disjunction and of partial trisomy translocation or insertion. Two cases of the partial trisomy in the E group are described; these are of especial interest because of the familial incidence, longer survival and male sex occurrence, features which are rarely seen in the full E-trisomy syndrome.     

Report of a trisomy 8p infant with carrier father.

This report describes an infant with fatal congenital heart disease, cleft palate, brain malformations, and trisomy 8p resultant from the paternal balanced reciprocal translocation, rcp(8;15) (p11;p11). Review of six previously reported trisomy 8p patients (resultant from parental balanced translocation in each instance) revealed severe mental retardation in five, short stature in all, and a variety of brain, skeletal, and cardiac defects. The features of the seven trisomy 8p patients reviewed here are not sufficiently similar to suggest a distinct dysmorphic syndrome. In addition the features differ from those in the trisomy 8 mosaicism syndrome, in which the mental retardation and malformations are generally less severe.     

Partial trisomy of the distal part of 10q: a report of two Egyptian cases

Partial trisomy of the distal third of the long arm of chromosome 10 is a well defined but rare syndrome. Most cases result from an unbalanced translocation. Growth retardation, developmental delay and characteristic dysmorphic features are well described in the syndrome. This report includes 2 Egyptian cases with partial 10q trisomy involving different breakpoints. Cases were subjected to full clinical examination and detailed cytogenetic analysis using conventional and FISH studies. Results showed that the karyotype of case 1 was 46,XX,der(7)t(7;10)(p22;q23).ish(wcp7+;wcpl0+) and the karyotype of case 2 was 46,XX,der(7)t(7;10)(p22;q25).ish(wcp7+;wcp 10+). The chromosomal abnormalities in case 1 resulted from a paternal balanced translocation while case 2 resulted from a maternal balanced translocation involving chromosomes 10 and 7 in both cases. The probands' phenotypes were correlated to the breakpoints and compared to previously reported cases with partial trisomy 10q. Both cases had the well characterized phenotype of the distal trisomy of 10q in the form of mental retardation, microcephaly, characteristic dysmorphic facies and limb anomalies as trisomy in both cases involved the 10q25-->qter region. However, case 1 with 10q23-->qter duplication showed more severe clinical manifestations than case 2 with less extensive 10q25-->qter trisomy. These included severe failure to thrive, cardiac involvement and death from respiratory and heart failure. This study confirmed that unbalanced chromosome regions of the long arm of chromosome 10 play an important role in developmental malformations and that a more severe form is associated with involvement of 10q23. It also emphasizes the importance of increasing public awareness regarding these chromosomal rearrangements and the importance of genetic counseling and prenatal diagnosis to avoid recurrences and associated family stress. This was clearly demonstrated in the second family in this study as the couple refused any follow up or further investigations due to religious beliefs despite their social and educational level.     

Duplication 11 (q22----qter) in an infant. A case report with review

A male infant with partial duplication of the long arm of chromosome 11 (11q22----qter) is described with a hitherto unreported translocation. In most cases 11q trisomy is associated with 11q/22q translocation and a 3:1 meiotic disjunction with 47 chromosomes. In a few cases the 11q translocation is associated with a partial deletion of other autosomes and a total of 46 chromosomes. In the present case, translocation to 9p is involved and no apparent deletion of 9p was noted, providing an opportunity to delineate the phenotypic features due to duplication of 11q. A comparison is made between the findings of partial 11q trisomy and 11q/22q translocation.