Partial monosomy 13q and partial trisomy 18p: case report with necropsy findings.

We describe a stillborn female infant with severe intrauterine growth retardation and multiple congenital anomalies. She was found to have a deletion of 13q22----qter and trisomy of 18p11.2----pter, resulting from a maternal balanced translocation.     

Simultaneous partial monosomy 10p and trisomy 5q in a case of hypoparathyroidism.

We report a case of monosomy for the distal region of the short arm of chromosome 10 (p13----ter) associated with trisomy for the terminal region of the long arm of chromosome 5 (q35.2----ter) that had originated from adjacent 1 segregation of a maternal reciprocal balanced translocation (5;10)(q35.2;p13). We review the clinical findings of previously reported cases of both partial monosomy for 10p and of partial trisomy for 5q, but to our knowledge there are no previous reports of the effects of these two chromosome anomalies together. Clinically our patient showed features typical of partial monosomy for 10p (including hypothyroidism) rather than partial trisomy 5q.     

Family with partial monosomy 10p and trisomy 10p

We report on a family with an abnormality of 10p. The propositus has monosomy for the distal region of 10p and severe psychomotor delay, growth failure, congenital heart defect, multicystic kidney, grade V vesicoureteric reflux, and neurosensory hearing loss. The mother and the elder brother of the propositus carry a balanced reciprocal translocation (5q;10p)(q35.3;p12.3). A retarded and epileptic maternal aunt was found to have dup(10p). Study of the family history led to the successful obstetric management of a subsequent twin pregnancy in which an affected fetus with dup(10p) was identified and selectively terminated, while the other normal twin was delivered at term without problems. © 1995 Wiley-Liss, Inc.     

Partial trisomy 17q22-qter and partial monosomy Xq27-qter in a girl with a de novo unbalanced translocation due to a postzygotic error: Case report and review of the literature on partial trisomy 17qter

Partial trisomy 17q22-qter is a rare but well-recognized clinical entity. We present a case of partial trisomy for the long arm of chromosome 17, which was detected in a female infant with severe psychomotor and somatic retardation, Stargardt disease, short limbs, and numerous minor anomalies. Differential chromosomal staining demonstrated an excess of genetic material on the long arm of the late replicating X chromosome. FISH and DNA polymorphism analysis showed that the extra material belonged to the distal part of the long arm of chromosome 17 and that there was a partial monosomy of the distal part of the long arm of the derivative X chromosome. The breakpoint regions of this translocation were identified by molecular analysis using polymorphic microsatellite markers on human chromosomes 17 and X. The origin of the abnormal X chromosome was found to be paternal, whereas the origin of the duplicated part of chromosome 17 was maternal. The unbalanced translocation between the paternal X and the maternal chromosome 17 is, therefore, suggested to be due to a postzygotic error. Am. J. Med. Genet. 70:87–94, 1997. © 1997 Wiley-Liss, Inc.     

A case of de novo trisomy 12p syndrome

A case of pure 12p trisomy was discovered in a 14-year-old boy during a cytogenetic survey of Egyptian students attending a school for mentally retarded children. The patient had a normal birth weight but later showed developmental delay. Clinical examination at 14 years of age revealed a high bulging forehead, broad and flat nasal bridge, large mouth with everted lower lip, folded upper ear helix with protuberant antihelix, pectus excavatum, undescended testes, flat feet, generalized hypotonia and moderate mental retardation. Chromosomes analyzed from blood lymphocytes showed an enlarged short arm with an additional band on one of the no. 12 chromosomes. The duplicated chromosomal material extended from 12pter----p12.2, including the LDH-B locus, which showed a gene-dosage effect. This extra chromosomal material arose de novo by tandem duplication. The parents' chromosomes were normal.     

Prenatal detection of monosomy 18p and trisomy 18q mosaicism with unexpected fetal phenotype.

A mosaic karyotype 46,XX,del(18)(p11)/46,XX,-18,+?i(18q) was found in cultured amniotic cells. Fetal blood sampling confirmed the presence of both cell lines. The pregnancy was terminated and the two cell lines were demonstrated in varying proportions in the fetal tissues. The few abnormal features seen in the fetus may represent a mild expression of the 18p-- phenotype inhibiting the effects of the trisomy 18q.     

Partial 18q trisomy and 18p monosomy resulting from a maternal pericentric inversion, inv(18)(p11.2q21.3).

A 7-year-old boy with dysmorphic features was found to have a recombinant chromosome 18, rec(18), resulting from meiotic recombination of a maternal pericentric inversion, inv(18) (p11.2q21.3), as defined by high-resolution banding. He was trisomic for the long arm (q21.3-qter) and monosomic for the short arm (p11.2-pter) of chromosome 18. His clinical features were compared with those in other rec(18) cases, and also those in monosomy 18p, trisomy 18qter and full trisomy 18 syndromes. The risk of recombinant formation for inv(18) carriers was also discussed.     

Partial 18q trisomy and 18p monosomy resulting from a maternal pericentric inversion,inv(18)(p11.2q21.3)

A 7-year-old boy with dysmorphic features was found to have a recombinant chromosome 18, rec(18), resulting from meiotic recombination of a maternal pericentric inversion, inv(18) (p11.2q21.3), as defined by high-resolution banding. He was trisomic for the long arm (q21.3-qter) and monosomic for the short arm (p11.2-pter) of chromosome 18. His clinical features were compared with those in other rec(18) cases, and also those in monosomy 18p, trisomy 18qter and full trisomy 18 syndromes. The risk of recombinant formation for inv(18) carriers was also discussed.     

Neonatal death in cousins with trisomy 10q and monosomy 4p due to a familial translocation

Two cousins with trisomy for a part of the long arm of chromosome 10 and monosomy for the distal portion of the short arm of chromosome 4 are reported. These infants had severe, neonatally lethal, multiple malformations. Certain of these malformations - including severe lower limb reductions, marked ophthalmologic anomalies and certain craniofacial features - are inconsistent with either a simple additive effect of the two component chromosomal anomalies, or chromosomal "epistasis" that would result in observing the phenotypic effect of only one of the chromosomal aberrations. Rather a synergistic effect of these two karyotypic anomalies has resulted in unique phenotypic features.     

Prenatal diagnosis of a de novo trisomy 6q22.2→6qter and monosomy lpter→1p36.3. Case report with a 2-year follow-up and a brief review of other prenatal cases of partial trisomy 6q

We report a de novo trisomy 6q22.2→6qter and monosomy lpter→1p36.3 identified in amniocytes by GTG banding and FISH. While ultrasonography demonstrated malformations that did not suggest a specific chromosomal syndrome, a male infant with features consistent with trisomy 6q was born. He was followed up until 23 months, when he died after cardiac surgery. The only two other prenatal cases of trisomy 6q were compared with our patient. A literature review showed that trisomy 6q has not been reported in association with the anomalies seen by ultrasound in this case.     

Factor VII deficiency and developmental abnormalities in a patient with partial monosomy of 13q and trisomy of 16p: case report and review of the literature

Background  

Unbalanced chromosomal translocations may present with a variety of clinical and laboratory findings and provide insight into the functions of genes on the involved chromosomal segments.     

Partial trisomy 12q: report of a case and review.

A malformed male infant with pure partial trisomy 12q (q24.1 leads to qter), resulting from an unbalanced segregation of a paternal balanced translocation t(2;12)(q37;q24.1), is described. The cytogenetic and clinical abnormalities of the proband are compared with those of four previously reported cases of partial trisomy 12q, two of which also appear to have pure trisomy of segment 12q24.1 leads to 12 qter.     

Severe mental retardation in a boy with partial trisomy 10q and partial monosomy 2q.

A severely mentally subnormal child with many physical stigmata was shown to have the karyotype 46,XY,-2,+der(2),t(2;10)(q31;q24)pat. Full evaluation of this patient's karyotype depended on the family studies. It was shown that a balanced translocation t(2,10) was present in 4 normal males in 3 generations.     

A girl with metopic synostosis and trisomy 13 mosaicism: case report and review of the literature

Trisomy 13, or Patau syndrome is a rare chromosomal disorder characterized by a triad of cleft lip and palate, postaxial polydactyly and microcephaly. Complete, partial, or mosaic forms of the disorder can occur. Mosaic trisomy 13 is very rare, it occurs in only 5% of all patients with trisomy 13 phenotype. Metopic synostosis (MS) is premature fusion of the metopic suture, which is part of the frontal suture. It results in a V-shaped abnormality at the front of the skull. MS may occur in a syndromic or nonsyndromic form. We report on a 24-day-old girl with hypotonia, MS, trigonocephaly, capillary hemangioma, hypotelorism, upward slanting palpebral fissures, epicanthal folds, small nose with anteverted nares, high palate, ankyloglossia, long philtrum, low-set ears, short neck, postaxial polydactyly of both hands and feet and congenital heart defect. Cytogenetic analysis demonstrated trisomy 13 mosaicism; 46,XX[58]/47,XX,+13[42]. Although MS has been previously reported in complete and partial forms of trisomy 13, it has not been reported in mosaic form of trisomy 13. Our report supports the evidence that trisomy 13 causes MS. It also emphasizes the need for cytogenetic investigations in patients presenting with MS and multiple congenital anomalies for providing accurate diagnosis, genetic counseling, and prenatal diagnosis.     

Three children with partial trisomy 1q and partial monosomy 3p.

We report a kindred in which three children suffer from partial trisomy 1q and partial monosomy 3p, transmitted by a balanced translocation which is maternal in one family and paternal in the other. The clinical features of the three children are similar and include severe mental handicap and severe scoliosis in the older two.