Prenatal diagnosis of de novo partial trisomy 18p and partial monosomy 18q recurrent in a family with fatal aortic coarctation

Aortic coarctation is a life-threatening defect when it occurs with cardiorespiratory failure. Its genetic cause remains unknown. A woman was pregnant twice, both with male fetuses that had partial trisomy 18p, partial monosomy 18q, and aortic coarctation. The syndrome may relate to the aortic coarctation and pulmonary hypoplasia and is life-threatening. ArrayCGH analysis suggested a de novo 17.7 Mb deletion of chromosome 18q21.33 → qter (58,413,193 bp to 76,116,029 bp) and a de novo 12.4 Mb duplication of chromosome 18pter → p11.21 (1543 bp to 12,438,430 bp) at the telomeric end of chromosome 18. To the best of our knowledge, the present chromosomal breakpoint with rearrangement has not been previously described. This chromosome aberration may be responsible for this syndrome.     

Partial trisomy 8q and partial monosomy 18p: a case report

We report clinical observations and cytogenetic studies of an inherited partial trisomy 8q and partial monosomy 18p. A full trisomy 8 syndrome (Warkany syndrome) is a clinically recognized syndrome. Partial trisomy 8q has been reported sporadically in the literature with variable phenotypes. Partial monosomy 18p, deletion of the short arm of chromosome 18, is also a well-recognized syndrome. This is the first report to the best of our knowledge of partial trisomy for distal 8q and partial monosomy for distal 18p occurring together in a patient.     

De novo partial 2q3 trisomy/distal 7p22 monosomy in a malformed newborn with 7p deletion phenotype and craniosynostosis

In the present paper a malformed male newborn is presented with de novo 2q3 trisomy/distal 7p22 monosomy and typical clinical findings of 7p deletion syndrome including trigonocephaly.     

Precocious puberty associated with partial trisomy 18q and monosomy 11q

We report a 10-years-old female patient with a partial trisomy 18q and monosomy 11q due to a maternal translocation. The phenotype of our proband is partially common with Jacobsen syndrome and duplication 18q but she has also some atypical anomalies such as precocious puberty, a retinal albinism and hypermetropia. Based on cytogenetics and FISH analysis, the karyotype of the proband was 46,XX,der(11)t(11;18)(q24;q13). To the best of our knowledge, this is the first report of precocious puberty associated with either dup(18q) or del(11q) syndromes.     

Multiorgan autoimmunity in a Turner syndrome patient with partial monosomy 2q and trisomy 10p

Turner syndrome is a condition caused by numeric and structural abnormalities of the X chromosome, and is characterized by a series of clinical features, the most common being short stature and gonadal dysgenesis. An increased frequency of autoimmune diseases as well as an elevated incidence of autoantibodies has been observed in Turner patients.     

Partial monosomy 9p (9p22.2-->pter) and partial trisomy 18q (18q21.32-->qter) in a female infant with anorectal malformations

We report a female infant with a karyotype of 46,XX,der(9)t(9;18)(p22.2;q21.32)pat and the phenotypic features of craniofacial dysmorphisms, developmental delay, hypotonia, horizontal nystagmus, strabismus, congenital heart defects, clubfoot, and anorectal malformations with an anterior ectopic anus and a stenosed anal opening. Array comparative genomic hybridization revealed a 16.93-Mb deletion at 9p24.3-p22.2 encompassing the FREM1 gene and a 20.43-Mb duplication at 18q21.32-q23 encompassing the PIGN gene. We speculate that dual genome imbalances in FREMI at 9p22.3 and in PIGN at 18q21.3 are most likely responsible for the abnormal development of anorectum in this patient.     

De novo distal trisomy 17q

A boy is described, who shares many of the clinical features found in the few patients with a partial 17q trisomy known at present. Karyotyping revealed a de novo 17q+ chromosome, interpretable as a tandem duplication of the distal long arm region 17q25.     

Recurrent proximal 18p monosomy and 18q trisomy in a family with a maternal pericentric inversion of chromosome 18

We report a recurrent partial monosomy of 18p10-->11.2 and proximal partial trisomy of 18q10-->21.3 caused by a maternal pericentric inversion of chromosome 18, involving breakpoints p11.2 and q21q21.3 Based on cytogenetics and FISH analysis, we speculate that the recurrent chromosome abnormality in the proband and in the fetus was the result of a translocation, possibly in a germ cell or germ cell precursor, between the maternal normal 18 and her inverted 18, resulting in maternal germinal mosaicism, i.e. 46,XX,inv(18)/46,XX,t[18;inv(18)][q10;q10]. The unbalanced karyotype of the proband and the fetus is 46,XY,+18,der[18;inv(18)][q10;q10]. To the best of our knowledge, there are no reports of this combination of proximal 18p monosomy and proximal 18q trisomy. The other interesting observation was association of Hirschsprung's disease in the proband.     

De novo unbalanced t(11q;21q) leading to a partial monosomy 21pter-q22.2 and 11q24-qter in a patient initially diagnosed as monosomy 21

We describe a patient in whom full monosomy 21 was initially assumed from routine GTG banded karyotyping. Re-examination with chromosome painting demonstrated an unbalanced translocation between the long arms of chromosomes 11 and 21. Fluorescence in situ hybridization (FISH) and microsatellite marker analysis revealed partial monosomy of chromosome 21 (pter-q22.2) and 11 (q24-qter). The patient was prematurely born in the 31st week of gestation and expired 3 days after delivery. She showed multiple minor anomalies, a complex cardio-vascular malformation, intestinal malrotation and cerebellar hypoplasia.     

Genotype/phenotype correlation in a patient with partial monosomy 15 and partial trisomy 14

We report on a girl with severe mental and psychomotor retardation caused by an unusual, unbalanced translocation t(14;15) of maternal origin. The unbalanced translocation in the patient resulted in trisomy 14pter-->q13 and monosomy 15pter-->q11.2. In addition to common features described in other patients with small proximal trisomies of chromosome 14, our patient presented with hypopigmented skin with light hair and eye color and severe speech impairment. Therefore the phenotype of the girl shows few similarities to that of Angelman syndrome patients, although the breakpoint in chromosome 15 in our patient was found to be proximal to the PWS/AS region.     

De novo appearance of a partial trisomy 1q in mosaic due to a 1;9 translocation

A child with trisomy 1q24----qter is described. This syndrome is compared to other 1q partial trisomies. An association is proposed between these trisomic segments and the following phenotypic signs: microphtalmia, trigonocephaly, hypertrichosis, antimongoloid eye slants, anomalies of the biliary tract, and malformations of the central nervous system.     

Partial trisomy 7q and probable partial monosomy of 5p in the son of a mother with a reciprocal translocation between 5p and 7q

Summary An underweight male newborn revealed a complex pattern of abnormal findings including severe neurologic dysfunction, a catlike cry, defective ossification of the calvarian bones, hypertelorism, downward slanting palpebral fissures, epicanthal folds, a short and flat nose with a flattened bridge, broad thumbs, clenched fingers 3–5 on the right hand, simian creases, a congenital heart defect, internal hydrocephalus, and bilateral hydronephrosis. He died on day 26 of his life. Chromosome examination disclosed a maternally inherited reciprocal translocation between 5p and 7q, resulting most probably in monosomy of 5q15 and trisomy of 7q32qter (46,XY, der (5), t(5;7)(p15;q32)mat).     

Different conformation of two supernumerary 18p isochromosomes, one with a concomitant partial 18q trisomy

The presence of a supernumerary 18p isochromosome is a rare chromosomal abnormality that results in 18p tetrasomy. This is a report on the clinical, cytogenetic and molecular findings of 2 non-related patients with a supernumerary 18p isochromosome. Both patients present some features of the 18p tetrasomy syndrome (strabismus, low-set ears, long and narrow fingers and toes), but additional characteristics were also observed. Cytogenetic analysis, FISH, MLPA and SNP array techniques showed that one of the isochromosomes is symmetric and monocentric, while the other is asymmetric and dicentric, yet resulting in a similar tetrasomy of the 18pter-18p10 region, followed by a partial 18q11.2 trisomy, an unprecedented finding in the literature.     

Partial trisomy 10p12.33 and partial monosomy 13q32.1: case report and a literature review

We report on a preterm neonate with a deletion of the distal long arm of chromosome 13q32.1 and partial trisomy of the short arm of chromosome 10p12.33. The patient has intrauterine growth retardation, microphthalmia, macrocephaly, holoprosencephaly, patent ductus arteriosus, aortic isthmus hypoplasia, right renal agenesis, imperforate anus, ambiguous genitalia, pleural effusion and vertebral anomaly. Analysis using an oligonucleotide microarray (U-array Cyto6000 array platform (Human Genome build: hg 18) indicated that there was a partial trisomy of chromosome 10(19.5 Mb gain) involving 298 oligonucleotides from 10pter to 10p12.33, and a partial monosomy of chromosome 13(18.3 Mb deleted) involving 313 oligonucleotides from 13q32.1 to 13qter. This is the first report of a patient with partial trisomy 10p12.33 and partial monosomy 13q32.1.     

De novo 18q deletion with mitral valve insufficiency

We report an 18-year-old Turkish girl with an 18q- deletion and abnormalities of face, mental and growth retardation, mitral deficiency and hypothyroidism. Mitral deficiency has not been reported in 18q deletion syndrome cases previously. We performed cytogenetic and molecular cytogenetic analysis, and brain MRI. Her karyotype was 46,XX,del(18)(q21.2-->qter). This report compares the symptoms and features of the present patient with previously reported cases with 18q syndrome.     

‘De novo’ trisomy 16q11→pter

Summary A de novo 16q- trisomy was found in a patient with severe mental retardation and mild physical abnormalities.A preliminary delineation the clinical features characteristic of trisomy 16q- is proposed, based upon comparison of the two cases identified so far. The mild phenotypical effects of this chromosome imbalance suggest that the alleged lethality of partial chromosome 16 aneuploidies should be reconsidered.     

Partial monosomy 8p and partial trisomy 8p with moderate mental retardation.

A female patient with mosaicism for partial monosomy 8p and partial trisomy 8p is presented. Her karyotype is 46,XX, del(8)(p21)/46,XX, dup(8)(p21----pter). She showed minimal dysmorphic features, agenesis of the corpus callosum and moderate developmental delay. There is no previous report of mosaicism for partial monosomy and partial trisomy 8p. The clinical findings in the presently described patient are less severe than those reported in cases with only monosomy or trisomy of the distal part of chromosome 8.