46,XX,der(2)t(2;10)(2pter-->2q37::10p13-->10pter)[127]/45,X,der(2)t(2;10) (2pter-->2q37::10p13-->10pter)[23]. Karyotype-phenotype correlation and genetic counselling in complex karyotypes

We describe a female child with complex cytogenetic anomalies consisting in partial trisomy of the short arm of chromosome 10, terminal deletion of the long arm of chromosome 2 and--at the same time--a mosaicism for X monosomy. To our knowledge, this is the first case reported in which 10p trisomy is associated to a 2qter deletion. Due to the scarcity of cases reported with pure trisomy, it has not been possible to define the 10p+ syndrome precisely yet. Comparison of our proband's phenotype to both the 2q37 deletion and 10p trisomy showed more features described in 2q37- subjects than in 10p+ ones. We also discuss the difficulties of genetic counseling in children with complex aberrations.     

Partial trisomy 10p.

It is reported on a boy of 4 years 9 months with trisomy of the distal part of the short arm of a chromosome 10, due to a balanced 7/10 translocation in the father. Besides multiple minor dysmorphias the patient showed severe mental retardation, small stature, hypotonia, retarded bone age. The high and bulky forehead was especially remarkable, because this sign has also been noted in formerly reported cases with trisomy 10p.     

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.     

Molecular cytogenetics, RFLP analysis and clinical characterization of a de novo trisomy 10p case

A new case of a de novo trisomy 10cen-->10pter is described. The karyotype was exactly defined by high resolution banding and FISH analysis; the chromosome aberration was of maternal meiotic origin as demonstrated by RFLP analysis. Clinical data are reported and correlated with other trisomy 10p cases from the literature. A critical review of the literature was made to define the phenotype of trisomy 10p syndrome.     

Different phenotypes of the group-specific component (Gc) in chimpanzees

Summary A 21-year-old mentally retarded female with 10p12 trisomy is reported. She presented a slight craniofacial dysmorphism very similar to that found in the full 10p-trisomy syndrome. Other features usually found in full 10p trisomy, however, such as failure to thrive and internal malformations, were absent.     

Distal trisomy 10q/partial monosomy 14q: an unusual clinical picture

A case of twin boy with partial trisomy for the distal part of the long arm of chromosome 10 (10q24-->qter) and a concomitant monosomy 14(q32-->qter) is reported. The chromosomal abnormalities resulted from a paternal balanced translocation involving chromosomes 10 and 14. An additional clinical feature was observed, viz. hypoplastic lungs. The proband's phenotype was compared to previously reported patients with partial trisomy 10q or 14q deletion.     

Are cells with trisomy 10 always malignant in hematopoietic disorders?

Two patients with acute myeloid leukemia (AML-M7 and AML-M4) and trisomy 10 as the sole chromosome abnormality are reported. In the first patient, all karyotypes were abnormal. A karyotypically normal cell population was present in the second patient and the trisomic cells were less numerous than the normal ones at diagnosis. A review of the literature shows the rarity of isolated trisomy 10 in hematopoietic disorders and the diversity of the involved diseases. Moreover, in some patients, the trisomic cell population was less numerous than the normal one. These data are discussed in relation with the hypothesis that cells with trisomy 10 can belong to nonmalignant clones, at least in some cases, as previously shown for trisomy 7 in other conditions.     

Trisomy 9 mosaicism in a girl with multiple malformations

A one-year-old girl with a mosaicism for an extra chromosome 9 is reported. Clinical findings included severe growth and mental retardation, frequent respiratory infections, peculiar face, skeletal and craniofacial abnormalities, seizures, spasticity, cardiopulmonary, gastrointestinal and genitourinary alterations. These findings were compared to those of the 10 other previously reported cases of trisomy 9 mosaicism. This helps to define the most constant phenotypical characteristics and most frequent major malformations which occur in trisomy 9 mosaicism. It is noteworthy that the reported percentage of trisomic cells was different in lymphocytes and in fibroblasts in each case.     

Trisomy 7p: report of 2 patients and literature review

Two patients with a trisomy 7p are reported. Both were assessed by facial dysmorphism and congenital anomalies. In one of the patients trisomy 7p was a de novo event, in the other patient unbalanced inheritance of a parental translocation caused trisomy 7p. Developmental delay was severe in both. Our 2 cases are compared with patients reported in literature.     

Partial trisomy 10q

Summary Five cases from two nonrelated families with partial trisomy 10q due to a reciprocal translocation t(10;17)(q25;p13) and t(10;11)(q24;q23), respectively, are reported. The phenotypic findings are compared with those of 17 previously published cases; the clinical data justify the conclusion that cases with trisomy 10q show a specific syndrome of mental retardation and malformation characterized by psychomotor retardation, growth retardation, hypotonia, high forehead, flat face, fine and arched eyebrows, antimongoloid slant of the eyes, narrow palpebral fissures, hypertelorism, short nose, bowshaped mouth, short neck, (kypho)scoliosis, and in some cases microcephaly.     

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.     

Telomere lengths at birth in trisomies 18 and 21 measured by Q-FISH

Trisomies 18 and 21 are genetic disorders in which cells possess an extra copy of each of the relevant chromosomes. Individuals with these disorders who survive birth generally have a shortened life expectancy. As telomeres are known to play an important role in the maintenance of genomic integrity by protecting the chromosomal ends, we conducted a study to determine whether there are differences in telomere length at birth between individuals with trisomy and diploidy, and between trisomic chromosomes and normal chromosomes. We examined samples of peripheral blood lymphocytes (PBLs) from 31 live neonates (diploidy: 10, trisomy 18: 10, trisomy 21: 11) and estimated the telomere length of each chromosome arm using Q-FISH. We observed that the telomeres of trisomic chromosomes were neither shorter nor longer than the mean telomere length of chromosomes as a whole among subjects with trisomies 18 and 21 (intra-cell comparison), and we were unable to conclude that there were differences in telomere length between 18 trisomy and diploid subjects, or between 21 trisomy and diploid subjects (inter-individual comparison). Although it has been reported that telomeres are shorter in older individuals with trisomy 21 and show accelerated telomere shortening with age, our data suggest that patients with trisomies 18 and 21 may have comparably sized telomeres. Therefore, it would be advisable for them to avoid lifestyle habits and characteristics such as obesity, cigarette smoking, chronic stress, and alcohol intake, which lead to marked telomere shortening.     

Pure trisomy 17p in 60% of cells

Summary A patient with pure trisomy of the short arm of chromosome 17 in 60% of the examined cells is reported. She presented a variant chromosome 1 with partial pericentric inversion and increased centromeric heterochromatin in one chromosome 17. The cytogenetic findings are discussed. The clinical findings are compared to those found in other reported cases of partial trisomy 17 and a delineation of a pure trisomy 17p attempted.     

Two new cases of trisomy 10q21 to 10qter in two sisters due to paternal translocation t(9;10) (q34;q24)]

Two sisters with multiple congenital malformations were shown to be trisomic for 10q24 to 10qter as a consequence of malsegregation of the balanced paternal translocation t(9;10) (q34;q24). Comparison of their phenotype with that of other patients reported in the literature confirms the individuality of the partial 10q trisomy syndrome.     

Phenotypic and molecular characterization of partial trisomy 2q resulting from insertion-duplication in chromosome 18q: a case report and review of literature

Trisomy 2q is a well-documented chromosomal anomaly with considerable variation in the phenotype depending upon the breakpoints and the co-existing chromosomal aberrations. The case of a dysmorphic male infant found to have trisomy of the 2q31.1-q37.3 segment, resulting from insertion-duplication of this segment in chromosome 18q23 is reported here. The rearrangement was resolved in detail by cytogenetic microarray and whole chromosome paint-based fluorescence in situ hybridization studies. There is some overlap of the phenotypic features in the reported patient with those described in previously reported cases with partial trisomy 2q. A detailed review of the available literature on 2q trisomy has also been presented and delineation of the phenotypic characteristics common to all patients with 2q trisomy has been attempted.     

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 neonatal case of left ventricular noncompaction associated with trisomy 18

A neonatal case of left ventricular non-compaction associated with trisomy 18: Left ventricular noncompaction (LVNC) is a rare congenital cardiomyopathy and exact etiology is still unknown. Trisomy 18 is the second most common autosomal trisomy in live-born infants. LVNC has been described in association with other dysmorphic features, association with trisomy 18 has not been reported previously in a neonate. LVNC broadens the cardiac anomalies associated with trisomy 18.     

Trisomy 17 in a baboon (Papio hamadryas) with polydactyly, patent foramen ovale and pyelectasis

Trisomy 13 in humans is the third most common autosomal abnormality at birth, after trisomy 21 and trisomy 18. It has a reported incidence of between 1:5,000 and 1:30,000 live births. It is associated with multiple abnormalities, many of which shorten lifespan. We describe here the first reported case of a baboon (Papio hamadryas) with trisomy of chromosome 17, which is homologous to human chromosome 13. The trisomic infant was born to a consanguineous pair of baboons and had morphological characteristics similar to those observed in human trisomy 13, including bilateral polydactyly in the upper limbs, a patent foramen ovale, and pyelectasis. Molecular DNA analysis using human chromosome 13 markers was consistent with the affected infant inheriting two copies of chromosome 17 derived from the same parental chromosome. This trisomy was, therefore, due to either an error in meiosis II or the result of postzygotic nondisjunction. The parental origin, however, could not be determined.