Translocation between chromosome 7 and chromosome 22, t(7;22)(p22;q12), in a patient with chronic myelocytic leukemia

Summary A 46-year-old man with chronic myelocytic leukemia had a new variant translocation between chromosome 22 and chromosome 7 in bone marrow cells. No involvement of chromosome 9 was seen. The patient entered blastic transformation within half a year, by which time he had acquired an isochromosome 17 in addition to the variant translocation.     

Holoprosencephaly in a fetus with a 46,XX,der(7), t(7;8)(q36.1;p12) mat karyotype

In this report we present a female fetus with hemilobar holoprosencephaly and 46,XX,der(7)t(7;8)(q36.1;p12) mat karyotype. The holoprosencephaly-sequence is apparently related with the distal 7(q36.1----qter) deficiency.     

Siblings with opposite chromosome constitutions,dup(2q)/del(7q) and del(2q)/dup(7q)

Chromosome 7q36 microdeletion syndrome is a rare genomic disorder characterized by underdevelopment of the brain, microcephaly, anomalies of the sex organs, and language problems. Developmental delay, intellectual disability, autistic spectrum disorders, BDMR syndrome, and unusual facial morphology are the key features of the chromosome 2q37 microdeletion syndrome. A genetic screening for two brothers with global developmental delay using high-resolution chromosomal analysis and subtelomeric multiplex ligation-dependent probe amplification revealed subtelomeric rearrangements on the same sites of 2q37.2 and 7q35, with reversed deletion and duplication. Both of them showed dysmorphic facial features, severe disability of physical and intellectual development, and abnormal genitalia with differential abnormalities in their phenotypes. The family did not have abnormal genetic phenotypes. According to the genetic analysis of their parents, adjacent-1 segregation from their mother's was suggested as a mechanism of their gene mutation. By comparing the phenotypes of our patients with previous reports on similar patients, we tried to obtain the information of related genes and their chromosomal locations.     

Double translocation t(7;12),t(2;6) heterozygosity in one family

Summary Double translocation heterozygosity t(2;6),t(7;12) in three generations of a Dutch family is described: the segregation of a double translocation in more than one generation has not been previously published. The index case was a 16-year-old mentally retarded boy with partial trisomy 12p who showed several dysmorphic features such as high prominent forehead, flat face, flat and short nose bridge, short nose, dysplastic ears, prominent lower lip, and several skeletal abnormalities. Based on the findings in this patient and those in nine other cases, the existence of a specific trisomy 12p syndrome is postulated.     

A reciprocal translocation, t(6p+; 14q-), in the pig

A reciprocal translocation, identified as t(6p+; 14q-), is described in a 38,XX intersex pig. It is the fourth reciprocal translocation to be reported for this species, whereas Robertsonian translocations, of frequent occurrence in cattle and sheep, are so far unknown in domestic pig breeds.     

Unbalanced 1q whole-arm translocation resulting in der(14)t(1;14)(q11-12;p11) in myelodysplastic syndrome

Unbalanced whole-arm translocations (WATs) of the long arm of chromosome 1, resulting in complete trisomy 1q, are chromosomal abnormalities detectable in both solid tumors and hematologic neoplasms. Among the WATs of 1q to acrocentric chromosomes, a few patients with der(1;15) described as a dicentric chromosome have been reported so far, whereas cases of der(1;14) are much rarer. We report on a case of der(1;14) detected as single anomaly in a patient with myelodysplastic syndrome. The aim of our work was to investigate the breakpoints of the (1;14) translocation leading to the der(1;14). Fluorescence in situ hybridization (FISH) experiments have been performed on chromosome preparations from bone marrow aspirate, using specific centromeric probes of both chromosomes, as well as a probe mapping to 1q11 band. FISH results showed that in our patient the derivative chromosome was monocentric with a unique centromere derived from chromosome 14. The breakpoints of the translocation were located in the short arm of chromosome 14 and in the long arm of chromosome 1, between the alphoid D1Z5 and the satellite II domains. The 1q breakpoint was within the pericentromeric region of chromosome 1, which is notoriously an unstable chromosomal region, involved in different chromosomal rearrangements.     

Tertiary trisomy 14q-, due to paternal balanced translocation 46,XY,t(1;14)(q44;q22)

Summary Retardation of growth and mental development, craniofacial dysmorphy, limb anomalies, cryptorchidism and repeated infections are observed in a child with 47,XY,+der(14),t(1;14)(q44;q22)pat.     

Balanced familial translocation t(5;19)(q12;p or q11) with phenotypical abnormalities in a girl.

Human diploid fibroblasts cultured in Dulbecco's Modified Eagle's medium (DME) were exposed to different concentrations of 15 antibiotics to determine the limiting toxic concentration. The number of cells surviving after antibiotic treatment was given as the index of toxicity. No visible chromosomal damage could be detected when half the maximal toxic concentration was applied. The maximum limiting concentration was found to be the same for both the preconfluent and postconfluent phases.     

A jumping translocation (5p;15q), (8q;15q), and (12q;15q) (author's transl)]

Three balanced karyotypes (5p;15q), (8q;15q), and (12q;15q) were found simultaneously in a child with the Willi-Prader syndrome. The hypothesis is presented of a "jumping# translocation by affinity of telomeric and interstitial palindromes. The relationship between the Willi-Prader syndrome and a juxtacentric anomaly of the long arm of chromosome 15 is discussed.     

18p deletion syndrome with a 45, XY, t (14; 18) (p11;q11.2), -18, karyotype.

A dysmorphic male child of 8 months age presented with microphthalmia, micrognathia, hypertelorism, wide anterior fontanelles, large forehead, short neck, prominent ears, macrotestis and delayed developmental milestones. The patient presented with generalised seizures hydrocephalaus and Coarctation of aorta (Pre subclavian). He also had mild hypocalcaemia with normal renal function. Cytogenetic study revealed 18p(-) picture due to translocation between 14 p & 18q. Since the spectrum of clinical expression is similar to that is seen in 18p(-) syndrome it is suggested that not only whole of 18p but part of chromosome no. 18 proximal to 18 q 11.2 may also be involved in this phenotype.     

Constitutional mosaic t(2;7)(q33;p22) and other rearrangements in a girl with Wilms' tumor

A 2-year-old girl with sporadic unilateral Wilms' tumor (WT) not associated with aniridia was found to have, besides other chromosome abnormalities, a t(2;7)(q33;p22) in 6% of her lymphocytes. A comparison with 7 previous WT cases without aniridia in whom diverse chromosomal aberrations were present, reveals a wide heterogeneity and lead us to tentatively classify such changes as causal, secondary, and casual.     

46,XX, der(15),t(Y;15)(q12;p11) karyotype in an azoospermic male

We report on a Yq/15p translocation in a 23-year-old infertile male referred for Klinefelter Syndrome testing, who had azoospermia and bilateral small testes. Hormonal studies revealed hypergonadotropic hypogonadism. Conventional cytogenetic procedures giemsa trypsin giemsa (GTG) and high resolution banding (HRB) and molecular cytogenetic techniques Fluorescence In Situ Hybridization (FISH) performed on high-resolution lymphocyte chromosomes revealed the karyotype 46,XX, t(Y;15)(q12;p11). SRY-gene was confirmed to be present by classical Polymerase Chain Reaction (PCR) methods. His father carried de novo derivative chromosome 15 [45,X, t(Y;15)(q12;p11)] and was fertile; the karyotype of the father using G-band technique confirmed a reciprocal balanced translocation between chromosome Y and 15. In the proband, the der (15) has been inherited from the father because the mother had a normal karyotype (46,XX). In the proband, the der (15) could have produced genetic imbalance leading to unbalanced robertson translocation between chromosome Y and 15, which might have resulted in azoospermia and infertility in the proband. The paternal translocation might have lead to formation of imbalanced ova, which might be resulted infertility in the proband. Sister''s karyotypes was normal (46,XX) while his brother was not analyzed.     

A de novo 3p13 deletion induced by a complex chromosomal rearrangement combined with a pericentric inversion of chromosome,inv(3)(p13q12), and a translocation between chromosome 3 and 8, t(3;8)(q13.1;q24.2), in a child with developmental delay

A de novo complex chromosomal rearrangement is very rare but likely to be present in a child with developmental disabilities and physical alterations. A child presented in this study showed global developmental delay and some typical phenotypes. Initial karyotyping and FISH analysis in the patient showed an apparently de novo balanced translocation between chromosome 3 and 8, t(3;8)(q13.1;q24.2). Further analysis using multiplex ligation-dependent probe amplification and array-based comparative genomic hybridization revealed a cryptic microdeletion on 3p13 region. Nearly one-third of balanced rearrangements are reported to involve cryptic disruptions at breakpoints, however, the microdeletion of the proposita was present in non-translocated region of the chromosome 3. After careful reevaluation of the results, a pericentric inversion, inv(3)(p13q13.1) that induced deletion was revealed. The clinical features of developmental delay in cognition, language, and motor function and facial and physical phenotype of the proposita were similar to those found in the children with 3p13 deletion. This case shows that combined molecular cytogenetic techniques with routine karyotyping are very useful to identify subtle genomic changes associated with abnormal phenotypes.     

Balanced t(8;9)(q12;q33)pat carrier with phenotypic abnormalities attributable to a de novo terminal deletion of the long arm of chromosome 7

Summary A girl observed from birth to age 16 months had multiple congenital anomalies including growth and developmental retardation, microcephaly (-4 SD), bulbous nose, prominent lips and philtrum, esotropia, latent hypermetropia, and spasticity. Chromosome analysis showed her to be a balanced carrier of a t(8;9)(q12;q33)pat translocation. In addition, she had a de novo deletion of a distal segment of the long arm of chromosome 7. Seven Previously reported cases with deletions involving 7q were reviewed and had a number of nonspecific features in common, with microcephaly of a comparable degree in one of these. Studies of the Kidd (Jk) blood groups and Hageman factor were done because of the tentative assignment of their respective loci to distal 7q. Location of the Kidd (Jk) locus on the deleted segment can be excluded on the basis of heterozygosity of the proposita for the a and b alleles. Hageman factor was not decreased, which suggests that this locus is also not on the deleted segment.