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.     

Familial (9;11)(p22;p15.5)pat translocation and XX sex reversal in a phenotypic boy with cryptorchidism and delayed development

We describe a patient with the co-occurrence of a familial 9;11 reciprocal translocation and an XX sex reversal. The patient had cryptorchidism, delayed development, dysmorphic features and attention deficiency hyperactive disorder (ADHD). The proband's karyotype was 46,XX,t(9;11)(p22;p15.5) and he was positive for SRY gene. The father was found to be the carrier of the similar translocation. The co-occurrence of XX sex reversal and autosomal reciprocal translocation has not been described previously. The possible reasons for the manifestation of features other than those found in XX sex reversal is described.     

46,XX/46,XX,del (10) (p13)/47,XX,+r/47,XX,del (10) (p13), + r mosaicism and partial trisomy 10p phenotype (author's transl)]

The mosaicism 46,XX/46,XX,del(10)(p13)/47,XX, +r/47,XX,del(10)(p13), +r was found in the lymphocytes and the fibroblasts of a patient with the following : profound mental retardation; craniofacial dysmorphism with frontal bossing, fine eyebrows, a large hypoplastic nasal bridge, prognathism of the upper jaw, thick lips; a long and thin neck; congenital heart disease; skeletal malformations, with club feet; and hypotonia and lax ligaments. These malformations, compatible with the trisomy 10p syndrome, suggest that the supernumerary ring chromosome was composed of 10p material. An increase of HK1 and GOT1 activities was found. This is in favour of a partial trisomy of chromosome 10. The relative frequencies of the clones constituting the mosaic vary from tissue to tissue and with time.     

Familial (11;21)(p13;q22)pat balanced reciprocal translocation in a female child with regression of milestones

The role of balanced translocations in the human morphogenesis is difficult to interpret. A balanced reciprocal translocation (BRT) was observed in a female child referred with a history of regression of milestones. The cytogenetic findings by GTG-banding and fluorescence in situ hybridization revealed a BRT involving chromosomes 11p and 21q, i.e. 46,XX, t(11;21)(p13;q22). The father was found to be a carrier of the same BRT. This is the first report of reciprocal translocation involving 11p and 21q. The possible reasons for the manifestation of clinical features in the proband due to inherited BRT are discussed.     

Partial trisomy 11,46,XX,-3,-20,+der3,+der20,t(3:11:20), resulting from a complex maternal rearrangement of chromosomes 3, 11, 20

Summary Clinical findings of partial trisomy 11p are described in a patient bearing t(3;11;20) (p13;p11;q13). The translocation was present in balanced form in her mother (46,XX)t(3;11;20)(p13;p11;q13).     

Paternal reciprocal translocation t(11;16)(p13;q24.3) in a Silver-Russel syndrome patient

We describe a 7-month-old male child with Silver-Russel syndrome (SRS) phenotype, presented with two major clinical features: low birth weight, short stature, and minor features, such as macrocephaly, clinodactyly, essential for the diagnosis of SRS. Routine cytogenetic studies with GTG-banding showed 46,XY,t(11;16)(p13;q24.3). Fluorescence in situ hybridisation (FISH) with single copy probes BAC (11p13) and PAC (16q24.3), showed a reciprocal translocation. Chromosomal analysis of the mother was normal and the phenotypically normal father had apparently identical translocation t(11;16)(p13;q24.3). The disruption of growth factor genes at 11p and 16q breakpoint regions due to reciprocal translocation in the father might have caused SRS phenotype in the child.     

46,X,i(Xq)/47,XX,+13 mosaicism

A 10-year-old girl with short stature and other features of Turner's syndrome was found to be a mosaic consisting of 46,X,i(Xq) and 47,XX,+13 cell lines, a hitherto undescribed situation. She had none of the clinical features of trisomy 13 syndrome, with a possible exception of postaxial polydactyly of the left foot. Her PHA-stimulated blood lymphocytes and EB virus-transformed B lymphocytes both revealed the Xi(Xq)/XX,+13 mosaicism, while her skin fibroblasts showed an exclusively 46,X,i(Xq) karyotype. Studies using Q-and R-banding heteromorphisms as markers indicated that the patient started as a 13 trisomic zygote resulting from a maternal meiotic error, followed by the loss of chromosome 13 at an early mitotic division. C-banding analysis revealed two C banding blocks in the iso X chromosome, an indication that the chromosome was dicentric. BrdU-Hoechst-Giemsa analysis revealed that the iso X chromosome was late-replicating with both its arms either synchronously or asynchronously replicating. The iso X chromosome was thus designated as idic (Xq)(p11:p11). In view of the presence of the XX cell line, it was concluded that the patient started as an XX,+13 zygote, followed by two mitotic events, the loss of a chromosome 13 and the formation of the iso X chromosome, occurring either simultaneously or in succession.     

Deletion - translocation del (12) (p11) leads to (t10;12) (p13;pII).

Renewed examinatinon with improved banding techniques of a boy previously reported to have the karyotype 46, XY,del(12)(p11) revealed a translocation 46, XY,t(10;12)(p13;p11), and reexamination of a boy previously reported to have the karyotype 46,XY/46,XY,del(5)(p13) showed the same mosaicism, but with a significantly lower frequency of cells with del(5)(p13), 8% compared with 23% at the time of birth. The decrease of the frequency of cells with chromosome abnormality in mixoploids during the first years of life as found in the present case as well as in prevously reported cases is discussed.     

Interstitial deletion (2)(p13p15)

Summary A dysmorphic 5-year-old girl with severe growth and mental deficiency was studied. She presented a de novo interstitial 2p deletion. Karyotype: 46,XX,del(2)(p13p15).     

An apparent balanced translocation [t(9;11)(p21.2;p14.2)] in a neonate with dysmorphic features.

The role of so called balanced translocations in human morphogenesis remains puzzling. An eleven month old hispanic female was referred for neurological evaluation. The major dysmorphic features include: epicanthal folds, flat nasal bridge, small mouth, micrognathia, low set ears and cleft-palate. The cytogenetic findings by multiple banding techniques revealed an apparent balanced translocation involving chromosomes 9p and 11p i.e. 46,XX,t(9;11)(p21.2;p14.2) which, according to the authors, has not been previously reported.     

46,XX/46,XX,r (2)(p25q37) mosaicism: clinical and cytogenetic studies.

A severely mentally retarded and physically handicapped girl is described who has 46,XX/46,XX,r(2)(p25q37) mosaicism. This is the first ring 2 chromosome to be described in Man. Studies of the behaviour of the ring showed that it was stable in diploid cells which had increased in frequency over a period of seven years, but unstable in tetraploid cells which were at a much higher frequency than in normal individuals. It is concluded that in some cases the phenotypic consequences of ring chromosome formation may be due more to their disturbing the regulation of cell division than to the loss of genetic material. Current models of ring chromosome behaviour do not account for the induction of tetraploidy.     

46,XX/46,XX,del(20)(pter-->p12.2) mosaicism limited to fibroblasts associated with MCA/MR and severe growth deficit.

In this report the authors describe an 8-year-old severely mentally retarded girl with facial features resembling the facial dysmorphism seen in patients with Alagille-Watson syndrome, severe growth retardation and a 46,XX/46,XX,del(20)(pter-->p12.2) mosaicism in fibroblasts.     

A girl with the Prader-Willi Syndrome and Robertsonian translocation 45,XX,t(14;15)(p11;q11) which was present in three normal family members

Summary A 21-year-old girl with classical Prader-Willi Syndrome was found to have a 14;15 Robertsonian translocation—45,XX,t(14;15)(p11;q11). This type of Robertsonian translocation was not found in any patient from 8 surveys covering 6144 patients with mental retardation. Chromosome 15 has been involved in translocations in patients with the Prader-Willi Syndrome with greater than expected frequency. This is the first report of a 14;15 translocation and the Prader-Willi Syndrome. The same balanced translocation was present in the patient's mother and 2 normal siblings. Future genetic counselling for these 2 siblings will be difficult.     

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.     

Mosaic 13 trisomy due to de novo 13/13 translocation with subsequent fission. Karyotype: 46,XX,-13, +t(13;13)(p11;q11)/46,XX,del(13)(p11). A second example

In this paper we report a second example of 13 trisomy mosaicism due to de novo 13/13 translocation followed by postzygotic fission of the translocation chromosome in a polymalformed female newborn.     

Chromosome deletion [46,XX,del(20)(q11)] in agnogenic myeloid metaplasia

Summary A woman in the fourth year of agnogenic myeloid metaplasia was found to have partial deletion of the long arm of chromosome 20 [46,XX, del(20)(q11)] in mitoses of presumably immature myeloid cells from unstimulated cultures of peripheral blood and bone marrow. Cytogenetic studies of peripheral blood lymphocytes showed a normal female karyotype.     

Tertiary trisomy, 47,XX,+14q-, resulting from maternal balanced translocation, 46,XX,t(14;16)(q11;q24)

Summary A 3-year-old child with tertiary trisomy 14 (+14q-), daughter of a mother with a balanced reciprocal translocation [46,XX,t(14;16) (q11;q24)] is presented. Craniostenosis and developmental retardation were the primary presenting features in this patient.Operated by the University of Chicago for the U.S. Energy Research and Development Administration.This study was supported by the South Carolina Department of Mental Health.     

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.     

A dysmorphic newborn with 45,X,der(1)inv(1)(p13;qter)t(Y;1)(pter-->q11;p13),-Y de novo karyotype

A dysmorphic newborn with 45,x,der(1)inv(1)(p13;qter)t(y;1)(pter-->q11;p13),-Y de novo karyotype: Y/autosome translocations are very rare chromosomal rearrangements. In most cases, the long arm of the Y chromosome is translocated onto an autosome and most patients are referred because of male infertility. Y/1 translocations are very rare, and have been reported in seven patients so far. Pericentric inversions may be seen in all chromosomes and are not associated with phenotypic abnormalities. Here we report a 6-day old male baby with prenatal growth retardation, frontal bossing, hypertelorism, micrognathia, cleft soft palate, absent uvula, hypospadias, simian line in both hands and hammer toes. Cytogenetic analysis was performed with GTG-banding, C-banding and FISH analysis containing X centromeric probe, Yq12-qter locus specific probe and whole chromosome Y probe. An unbalanced Y/1 translocation was diagnosed: 45,X,der(1)inv(1)(p13;qter)t(Y;1)(pter-->q11;p13),-Y.     

Additional chromosome in a child as a result of a balanced reciprocal translocation t(12;18)(p13;q12) in his mother's karyotype

In this case report we present a child with an additional chromosome in the karyotype. The karyotypes of the boy and his parents were analyzed by use of a conventional banding technique (GTG) and fluorescence in situ hybridization (FISH). Probes painting whole chromosomes 12 and 18 were used in FISH. Cytogenetic examination of the parents revealed that his mother was carrying balanced reciprocal translocation between chromosomes 12 and 18. Her karyotype was described as 46,XX,t(12;18)(p13;q12). Father's karyotype was normal, described as 46,XY. The boy's karyotype was defined as 47,XY,+der(18)t(12;18)(p13;q12). The additional chromosome appeared probably due to 3:1 meiotic disjunction of the maternal balanced translocation, known as tertiary trisomy. The mother displayed a normal phenotype and delivered earlier a healthy child. However, the boy with the unbalanced karyotype shows multiple congenital abnormalities.