Partial duplication 14q/deletion 2q in two sibs due to t(2;14) (q37.1;q31.2) pat

Two siblings are described with duplication 14q/deletion 2q due to a paternal translocation (2;14) (q37.1;q31.2). The first one, a boy, born at term, lived 14 days. The second one, a female foetus, was born after induced labour when the anomaly was discovered by way of amniocentesis. They both had almost identical phenotypes. From a study of the literature it is inferred that a typical asymmetric head form, low set abnormal ears, micrognathia, long upper lip, rib anomalies, camptodactyly, long fingers and contractures are prominent features of the syndrome.     

A case of Alagille's syndrome with translocation (4;14) (q21;q21)

This paper reports a case of Alagille's syndrome, in association with a translocation 46,XY,t(4;14)(q21;21). The possible relationship between this autosomal dominant syndrome and the apparently balanced chromosomal rearrangement is discussed.     

Partial trisomy 14q due to maternal t(4;14)(p16;q32) in a dysmorphic newborn

Partial Trisomy 14q is a rare chromosomal disorder that mostly results from a parental translocation. We report here a newborn boy with partial trisomy 14q and dysmorphic features that are compatible with previously reported cases. Conventional cytogenetic analysis revealed an extra chromosomal segment at the end of the short arm of chromosome 4. In order to determine the origin of this chromosome region we used subtelomeric FISH technique. Based on the results of these cytogenetic studies and the physical examination, this dysmorphic case was diagnosed as partial trisomy of 14q and his karyotype determined as 46 XY, der(4)t(4;14)(p16;q32) resulting from a balanced maternal translocation identified as 46,XX, t(4;14)(p16;q32).     

Partial trisomy 15q due to maternal translocation t(7;15)(q35;14)]

Partial trisomy for the long arm of chromosome 15 was detected in a 21-year-old girl with severe growth and mental retardation. A balanced reciprocal translocation - t(7;15)(q35;q14) - is present in the mother.     

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.     

Partial trisomy 14q due to familial t(14q-, 11q+) translocation

Summary A malformed male newborn with partial trisomy for the distal part of the long arm chromosome 14 (14q₂₃14qter) is described. This anomaly arose as a segregation product of a balanced t(14q-, 11q+), translocation in the father.     

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.     

Meiotic segregation of chromosomes 13 and 14 in sperm of heterozygous Robertsonian translocation der(13;14)(q10;q10) carriers

Meiotic segregation of chromosomes 13 and 14 was assessed by fluorescence in situ hybridization on sperm of five heterozygous carriers of the most frequent Robertsonian translocation der(13;14). Alternate segregation mode was predominant (mean 78.2 ± 5.7%). The prevalence of balanced sperm varied from 69.4 to 86.5%. Adjacent segregation mode was detected in 18.64 ± 4.90% of sperm; 3:0 mode was detected in 2.48 ± 1.20% of sperm. These results are informative for reproductive counseling of Robertsonian translocation der(13;14) carriers providing information for assessment of probability of receiving normal/balanced embryos in assisted reproduction cycles.     

Immunoglobulin heavy chain and alpha T-cell receptor genes rearrange in T-cell leukemia associated with a t(14;14) (q11.2;q32) translocation

We report here a cytogenetic and molecular analysis of two cases of T-cell leukemia with t(14;14) (q11.2;q32). Through in situ hybridization and Southern blotting, using radioactively labeled immunoglobulin heavy chain (IGH) and alpha T-cell receptor (TCRA) gene probes, we found in both tumors that the loci of both IGH and TCRA were rearranged. Molecular analysis of the t(14;14) clearly demonstrated that in some tumors rearrangements of the IGH and TCRA genes are associated with interchromosomal exchanges that result in specific chromosome translocations that confer a proliferative advantage and predisposition to leukemic transformation. The implication of these rearrangements for normal and neoplastic T-cell development is discussed.     

The chromosome breakpoint at 14q32 in an ataxia telangiectasia t(14;14) T cell clone is different from the 14q32 breakpoint in Burkitts and an inv(14) T cell lymphoma

Summary The T cell receptor chain gene locus and the immunoglobulin heavy chain gene locus (IgH) have previously been mapped to the q11 and q32 positions respectively of the human chromosome 14. Both of these sites are also common breakpoints in lymphocytes from ataxia telangiectasia (A-T) patients. Using in situ hybridisation we show that the 14q32 breakpoint in an A-t non-leukaemic T cell clone with t(14;14) translocation, lies outside the IgH locus and proximal to it with respect to the centromere. The 14q11-14qter segment of the homologous chromosome 14 carrying the constant gene region of the chain locus is translocated to this 14q32 position.     

Prenatal diagnosis of partial trisomy 3q (3q27.3→qter) and partial monosomy 14q (14q31.3→qter) of paternal origin associated with fetal hypotonia,arthrogryposis, scoliosis and hyperextensible joints

We present rapid aneuploidy diagnosis of partial trisomy 3q (3q27.3→qter) and partial monosomy 14q (14q31.3→qter) of paternal origin by aCGH using uncultured amniocytes in a fetus with hypotonia, scoliosis, arthrogryposis, hyperextensible joints, facial dysmorphism, ventricular septal defect, pulmonary stenosis, clenched hands, clubfoot, scalp edema and right hydronephrosis. We discuss the genotype–phenotype correlation of 3q duplication syndrome and terminal 14q deletion syndrome. We demonstrate that fetuses with a paternal-origin deletion of 14q involving the 14q32.2 imprinted region may prenatally present the upd(14)mat-like phenotype such as hypotonia, scoliosis, arthrogryposis and hyperextensible joints.     

A 45,XX,-5,-14,+t(5q;14q)mat cri du chat child.

A two-year-old girl has the following features of the cri du chat syndrome: microcephaly, hypertelorism, downward slanting of the palpebral fissures, psychomotor retardation and a cat-like cry. She is only of five patients having the cat cry syndrome with 45 chromosomes. Her karyotype is 45,XX, -5, -14, +t(5; 14)(5qter leads to 5p11: : 14q11 leads to 14qter) with the translocation inherited from her mother and maternal grandmother, each of whom is the carrier of a balanced translocation 46,XX,t(5;14)(p11q11). Normal plasma activity for hexosaminidase B suggests the locus for this enzyme is not located in the delected segment of 5 p.     

Distal trisomy 14q

Summary Two cases of chromosome 14 rearrangements with partial duplication which occurred de novo were analyzed by Southern blot analysis using IGH, D14S1 and PI probes. In the first case, with a 46,XX,14p+ karyotype, our study confirms that the additional material on chromosome 14p+ results from a duplication of the 14q region containing the IGH, D14S1 and PI loci. In the second case, our study reveals only one 14q32 locus per chromosome 14 indicating that the extra material does not contain the 14q32 region. Our results demonstrate that molecular probes of the 14q32 region are valuable tools for the characterisation of chromosome 14 abnormalities appearing de novo.