Partial distal 10q trisomy due to de novo amplification: A new case without furrows or ridges in fingers and palms

Background:

Here we describe a new case of partial distal 10q trisomy in a 6-year-old Iranian girl from healthy parents with mental, growth, and psychomotor retardations.

Methods:

Additional clinical features include dysmorphic craniofacial features, microcephaly, bilateral hydronephrosis without heart problems, small and rotated low-set ears, bow-shaped mouth, abnormal teeth, short neck, and as a first case reported, fingers with camptodactly (i.e., without any furrows or ridges in the palms and fingers).

Results:

Cytogenetic analysis (GTG-banding) revealed an unbalanced female karyotype with additional bands at the end of the long arm of chromosome 10, karyotype: 46,XX,dup(10)(q25q26).

Conclusion:

According to the banding pattern it is most likely that a duplication of the distal part of the long arm of chromosome 10 occurred.Key Words: Trisomy, 10q, Distal, de novo     

Pure trisomy 19p syndrome in an infant with an extra ring chromosome

We report a 12-month-old infant evaluated for severe hypotonia, psychomotor retardation, and facial dysmorphisms, including round face, high prominent forehead, downward slanted palpebral fissures, hypertelorism, short nose, chubby cheeks, long philtrum, anteverted lower lip, low-set asymmetric and dysmorphic ears. Karyotype analysis disclosed an extra mosaic ring chromosome, which included the whole 19p arm. Four additional patients with supernumerary ring 19 chromosomes have been reported, but none of them had pure trisomy 19p.     

Large duplication 4q25-q34 with mild clinical effect

We report on a 5-year-old Tunisian boy with particular dysmorphic features and mild mental retardation limited in delayed and poor language acquisition. Cytogenetic analysis using RHG banding and FISH using whole chromosome four painting probe showed a partial duplication in the long arm of chromosome four. Locus specific probes and CGH confirmed the presence of a 'pure' partial trisomy 4q due to de novo direct tandem dup(4)(q25q34). Comparative analysis of our case with those published previously, suggests that region 4q31-q33 may be involved in the development of the 4q characteristic dysmorphic features and the distal band 4q35 may be involved in the development of microcephaly and severe mental and growth retardation.     

Partial trisomy of chromosome no. 1 in two adult brothers due to maternal translocation (1q-;6p+)

Summary Extra chromosome material on the short arm of chromosome no. 6 (46,XY,6p+) was found in two mentally retarded adult half-brothers with mildly dysmorphic features. The phenotypically normal mother had a balanced translocation between the long arm of chromosome no. 1 and the short arm of chromosome no. 6: 46,XX,t(1;6)(q32;p25). Thus the two affected brothers were trisomic for the long arm segment of chromosome no. 1, distal to q32. These patients, with mildly dysmorphic features and mental retardation, represent the first cases of partial trisomy 1q surviving to adulthood.The clinical and cytogenetic data obtained from eight individuals with partial trisomies for different long arm segments of chromosome no. 1 suggest that partial trisomy of the distal two-thirds of the long arm is characterized by severe malformations, growth retardation, and early death. Conversely, partial trisomy for the distal one-third of the long arm is associated with milder malformations and longer survival time as well as growth and mental retardation.     

Partial trisomy 8q in half-sisters with distinct dysmorphic patterns not similar to the trisomy 8 mosaicism syndrome

Summary Two cases of partial trisomy 8q are presented. Common clinical features included severe mental and physical retardation, a prominent and short forehead, widely set mongoloid eyes, broad, flat nose with short septum, short upper lip, misshapen ears, a funnel chest, hypertrichosis of the back, coxa valga, and short fingers with brachymesophalangy and clinodactyly of the little fingers. Moreover, Case 1 had a frontal meningocele and bilateral talipes equinovarus, and Case 2 had a ventricular septal defect. The chromosome aberration in the two girls arose from a maternal balanced translocation, t(8;18) (q2309;p113). Since the major clinical features of mosaic trisomy 8 are absent in the two girls and in other cases of partial trisomy, both for the distal segment of the lang arm and for the short arm of chromosome 8, it is concluded that trisomy of the proximal part of the long arm of chromosome 8 causes most of the clinical findings of trisomy 8 mosaicism syndrome.     

Two familial cases with trisomy 15q dist due to a rcp(5;15)(p14;q21)

Summary A trisomy of the distal long arm of chromosome 15 (q21qter) resulting in similar phenotypic and developmental abnormalities in two related children (a boy and a girl) is described. The chromosome defect was due to malsegregation of a balanced translocation (5;15)(p14;q21) in one of the parents. It was inherited in four generations and accompanied by recurrent miscarriages. Comparison of these patients with four previously published cases of trisomy 15q dist reveals a pattern of common features including: microdolichocephaly with characteristic strikingly protuberant occiput and predominance of the visceral over the cerebral cranium; peculiar facial dysmorphism—narrow antimongoloid palpebral fissures; large, malformed, low-set ears; micrognathy; long philtrum; short neck; cardiopathy; profound encephalopathy with lack of suck and swallow reflexes; and no growth retardation.     

A 3p deletion syndrome in a child with both del(3)(p25-->pter) and dup(17)(q23-->qter).

A child with monosomy for the distal part of the short arm of chromosome 3 (3p25-->pter) and trisomy for the terminal portion of the long arm of chromosome 17 (17q23-->qter) is presented. This unbalanced karyotype was derived from a balanced reciprocal 3p/17q translocation in the phenotypically normal mother. Main clinical features in the proband included growth and mental retardation, hypotonia, hirsutism, micro/brachycephaly, triangular face, synophris, broad and full nose, long philtrum, narrow upper lip, low set, posteriorly turned ears, anteriorly placed anus and congenital heart defect (Tetralogy of Fallot). Most of these clinical manifestations have been constantly reported in previous cases with terminal 3p deletion.     

Partial trisomy 10q in three unrelated patients

This communication describes three unrelated patients with growth and psychomotor retardation, multiple congenital anomalies, and dysmorphic features who were found to have trisomies for the different long arm segments of chromosome 10. After reviewing the clinical and cytogenetic data from the literature and our three patients we concluded that: a) There are at least two different clinical syndromes associated with long arm trisomy of chromosome 10 only one of which, the well known 10q trisomy syndrome, is characterized with specific clinical features. The only trisomic segment common in this latter group of patients with similar phenotype, yet with different trisomic segments, is the distal two bands, q25 and q26. Therefore the determinants for the well-delineated 10q trisomy syndrome seems to be located on the distal bands q25 and q26 and this syndrome would preferably be named "distal 10q trisomy syndrome". b) The patients with proximal and/or middle long arm segment trisomies of chromosome 10 are rare and they have yet undefined clinical features.     

Boy with seizures (West syndrome) and distal 7q duplication syndrome due to an unbalanced 7q;9p translocation

We report a 15 month old boy with prominent metopic suture, epicanthal folds, strabismus, low-set ears, microretrognathia, large anterior fontanel, bilateral simian creases, muscular hypotonia, and severe psychomotor retardation. He also had West syndrome. An electroencephalogram showed hypsarrythmia, and cranial MR indicated a myelinisation delay. Standard karyotyping showed additional material on one chromosome 9p. Using FISH, a terminal 7q duplication spanning 26 Mb in size and a terminal 9p deletion sized (at least) 9.1 Mb were identified. The father had a karyotype of t(7;9)(q33;p23) and the mother's karyotype was normal. The boy presented typical facial features of the distal 7q duplication syndrome but no genital anomalies attributable to his distal 9p deletion. We assume that the severe epilepsy is likely due to the trisomy 7q.     

‘Complete’ trisomy 5p; de novo translocation t(2;5)(q36;p11) with isochromosome 5p

Summary A case of complete trisomy 5p due to a de novo translocation t(2;5)(q36;p11) with an isochromosome 5p is described. Complete trisomy 5p has been reported only once (Brimblecombe et al., 1977). The confusing literature relating to partial trisomy 5p is reviewed. Comparison of our case with the patients reported by Brimblecombe et al. (1977) and by Opitz and Patau (1975) is suggestive for a distinct clinical syndrome if (almost) the complete short arm of chromosome 5 is present in a trisomic state. Unfortunately the clinical findings in the case of Brimblecombe (1966, 1977) are poorly documented. The main features of this syndrome are: macrocephaly, psychomotor retardation, hypotonia, postnatal growth failure, tracheobronchial involvement, mongoloid slant of the eyes, epicanthus, low-set ears, depressed nasal bridge, short first toe, and seizures.     

Partial trisomy 8p (8p11.2-->pTER) and deletion of 13q (13q32-->qTER): case report

We report a female infant with partial trisomy 8p (8p11.2-->pter) and deletion of 13q (13q32-->qter). She was born with mild hypotonia, intrauterine growth retardation, microcephaly, micrognathia, large low set ears, pectus excavatum, anteriorly placed anus, and bilateral clinodactyly. Echocardiography showed left ventricular hypertrophy, bicuspid aortic valve, dilatation of the aorta and pulmonary artery, and prolapse of atrio-venticular valve leaflets. Cytogenetic investigation of her sister and her father showed that the altered region resulted from a balanced translocation between the part of the long arm of chromosome 13 and short arm of chromosome 8. In partial trisomy 8p, the clinical picture of the patients comprises hypotonia, structural brain abnormalities, facial anomalies including a large mouth with a thin upper lip, a high arched palate, a broad nasal bridge, an abnormal maxilla or mandible, malformed, low set ears, and orthopedic anomalies. Although patients with proximal deletions of 13q that do not extend into band q32 have mild to moderate mental and growth delays with variable minor anomalies, patients with more distal deletions including at least part of band q32 usually have major malformations such as retinoblastoma, mental-motor growth retardation, malformation of brain and heart, anal atresia, and anomalies of the face and limbs. To our knowledge partial trisomy 8p and partial monosomy of 13q have not been reported previously in the same person.     

Chromosome 6q- and associated malformations.

A dysmorphic retarded fourteen-mont-old female with partial deletion of the long arm of chromosome 6 is presented. The breakpoint in 6q was in region 2, probably at band 5. Eight other infants with a deletion involving the long arm of chromosome 6, including five with a ring chromosome 6, have been reported. The affected individuals have in common microcephaly, micrognathia, hypotonia and psychomotor retardation, but do not appear to have a distinctive phenotype.     

Sensorineural deafness in two infants: a novel feature in the 22q distal duplication syndrome. Cardinal signs in trisomies 22 subtypes

Sensorineural deafness in two infants: a novel feature in the 22q distal duplication syndrome. cardinal signs in trisomies 22 subtypes: Distal trisomy 22 has been described in more than 15 individuals. The features are severe mental and growth retardation, failure to thrive, congenital hypotonia, hydrocephalus, microcephaly, cleft palate, epicanthic folds, low-set ears, broad prominent nasal bridge, long philtrum, micrognathia, finger-like thumbs, cryptorchidism. We describe a girl deceased at the age of 12 years and an 11 year old boy, both with a duplication of distal 22q due to a parental pericentric inversion (22) (p13q12). Their phenotypes are compatible with distal trisomy of chromosome 22. However, they did not present cleft palate, but the survival of both patients permitted us to discover sensorineural deafness not previously reported in this chromosomal duplication.     

Partial duplication of the short arm of chromosome 2 (dup(2)(p13----p21) associated with mental retardation and an Aarskog-like phenotype

In this report we describe a 3-year-old boy with partial trisomy of the short arm of chromosome 2 due to a de novo tandem duplication 2(dup(2)(p13----p21)). In addition to severe growth retardation and moderate psychomotor delay he presented a dysmorphic syndrome compatible with the clinical diagnostic of Aarskog syndrome.     

Further delineation of the clinical picture of trisomy for the distal segment of chromosome 13

Summary Three cases of partial trisomy for the distal segment of chromosome 13 are reported. Common clinical features included normal birth weight, postnatal asphyxia, convulsions, severe psychomotor retardation, normal growth, and a distinct pattern of dysmorphias consisting of trigonocephalic head with prominent metopic suture, long and markedly curved eyelashes, a stubby nose, increased distance between nose and upper lip, high-arched palate, misshapen ears with virtually absent lobules and prominent anthelices which are curved in a sharp angle, and hemangiomata. Features present in 2 cases were microcephaly, long and narrow fingers with convex nails, and hexadactyly. Two cousins were unbalanced offspring of a large family of carriers of a 9/13 translocation, whereas the third case exhibited a 13p+ chromosome which was formed de novo. The clinical features in the 3 patients are typical of the syndrome due to partial trisomy for the distal segment of chromosome 13 which shows selected and mitigated signs of full trisomy 13.     

18p- Syndrome resulting from 14q/18q ‘dicentric’ fusion translocation

Summary A child with nasal hypoplasia, growth and developmental delay, and 18p- due to 14q/18q apparent dicentric fusion is reported. Review of ten previously reported patients with 18p- due to fusion translocations involving the long arm of chromosome 18 reveals clinical features ranging from arrhinencephaly to minimal dysmorphic changes and mild retardation. This spectrum of clinical expression is similar to that seen in patients with partial 18p deletions. Since the same range of clinical features is observed whether there is partial or apparent total deletion of 18p, it is suggested that only a distal segment of the short arm of chromosome 18 may be etiologically related to the clinical phenotype in the 18p- syndrome.     

Distal duplication 14q: Report of three cases and further delineation of the syndrome

Summary Three cases of distal duplication 14q are presented. The first two cases are cousins in a kindred segregating a balanced translocation t(14;18)(q31;q23). The third case resulted from a maternal translocation t(14;18)(q24;p11). By review of these cases and those previously reported, a distal duplication 14q syndrome is further delineated. Common features include postnatal growth retardation, mental retardation, hypotonia, microcephaly, slanted palpebral fissures, ocular hypertelorism, sparse eyelashes and eyebrows, nasal dysmorphism, tented lip, micrognathia, posteriorly rotated ears, and minor skeletal anomalies.     

Fragile X chromosome and X-linked mental retardation.

A family is described in which three normal females transmitted to seven males X-linked mental retardation associated with macro-orchidism and a fragile site on the long arm of the X chromosome -- fra(X)(q27). The affected males also had minor clinical features in common: a large forehead, long face, large ears, a long upper lip and large extremities.     

Partial trisomy for the long arm of chromosome 7 due to familial balanced translocation

Summary A partial trisomy for the distal segment of the long arm of chromosome 7 (bands q32qter) was observed in a severely retarded child with somatic and CNS anomalies. The phenotypically normal father and paternal grandmother had a balanced reciprocal translocation between the long arm of a chromosome 2 and the long arm of a chromosome 7: 46,XX-XY,t(2;7) (q37;q32). The clinical features of the child at birth and at the ages of 5 months and 2 years are compared with those previously reported in cases of partial trisomy 7q.