An infant with duplication of 17q21→17qter

Duplication of the distal part of 17q has been reported in 4 patients [1, 2]. We are reporting clinical, autopsy, and cytogenetic data on an additional patient whose condition was due to a familial translocation in which the patient's chromosome constitution is 46,XX,der(4),t(4;17)(p16;q21) pat. The phenotype of the five known patients with this duplication is very similar, and their manifestations are distinct enough to be clinically recognizable. Abnormalities common to all five patients are severe growth impairment, craniofacial anomalies with severe hypertelorism, frontal bossing and temporal narrowness, a widow's peak, narrow palpebral fissures, a thin upper lip overlapping a thin lower lip with down-turned corners of the mouth, micrognathia, apparently low-set and deformed ears, short webbed neck, and hyperlaxity of the limbs.     

Duplication 6q22→qter: Definition of the phenotype

We report on a girl with duplication of 6q22.32 → qter and microcephaly, frontal bossing, facial anomalies, and webbed neck. She has congenital heart disease, renal hypoplasia, and hearing loss along with severe developmental delay. Published reports of seven other patients are reviewed and compared. The most frequent anomalies include microcephaly, abnormal face, webbed neck, congenital heart disease, limb contractures, and developmental delay. Am. J. Med. Genet. 78:123–126, 1998. © 1998 Wiley-Liss, Inc.     

Duplication 9q34→qter identified by chromosome painting

We have studied an infant with multiple anomalies and a 46,XY,12p+ karyotype. Parental chromosomes were normal, and it was not possible to determine the identity of the extra material on chromosome 12 cytogenetically. Chromosome painting with probes from a chromosome 9 library identified this material as coming from chromosome 9, and cytogenetics established the duplication as 9q34→qter. Comparison of this patient with others reported with partial dup(9q) documented excellent concordance of minor anomalies, most notably dolichocephaly, “;deep-set”; eyes, short horizontal palpebral fissures, beaked nose, micrognathia, arachnodactyly, and developmental delay. Identification of cytogenetically indeterminate abnormalities by molecular cytogenetics is very important, as it permits prognosis to be offered for families of newborn infants with unbalanced karyo-types. © 1993 Wiley-Liss, Inc.     

Duplication 6q24 → 6qter in an infant from a balanced paternal translocation

Duplication of 6q24 → 6qter was identified by GTG banding in an infant girl whose father was a balanced translocation carrier 46,XY,t(3;6)(p26 → q2402). At birth and at 4 mo she had proportionate short stature, microcephaly, asymmetric micrognathia, bow-shaped upper vermilion, long upper lip, submucous cleft palate, antimongoloid slant of palpebral fissures, telecanthus, prominant eyes, short neck with anterior and lateral webbing, short sternum, overlapping toes, wrist contractures, and hypertonicity. Later she was noted to have psychomotor retardation. Eleven previously published cases and our patient suggest that duplication of 6q (involving at least 6q25 → 6qter) produces a highly characteristic syndrome.     

Syndrome of facial,oral, and digital anomalies due to 7q21.2→q22.1 duplication

We report on an 18-year-old man with moderate mental retardation, multiple congenital anomalies and partial trisomy 7q21.2→q22.1, as the unbalanced product of a familial balanced 7q/6q insertion translocation. To the best of our knowledge, this is the first example of interstitial trisomy 7q21.2→q22.1 reported. The syndrome is characterized by the presence of facial, oral, and digital anomalies: 1) macrocephaly with frontal bossing, hypertelorism, small palpebral fissures with downward slant; 2) lobulated tongue, multiple intrabuccal frenula, oligodontia and enamel hypoplasia; 3) cutaneous syndactyly of fingers II-III and III-IV, broad and short fingertips with fetal pads, broad thumbs, and halluces. Am. J. Med. Genet. 80:454–458, 1998. © 1998 Wiley-Liss, Inc.     

Malformation syndrome of duplication 12q24.1→qter

While duplication and deletion of the short arm of chromosome 12 cause well-recognized syndromes, duplication of the long arm of chromosome 12 is rarely observed. We are reporting a duplication of chromosome 12 distal to band q24.1 in a five-month-old child. His chromosome constitution is 46,XY,-4, + der(4),t(4:12)(p16;q24.1)mat. The balanced translocation is also carried by his maternal grandmother and two of the mother's brothers. The malformation syndrome consisted of unusual facial appearance and anomalies of the musculoskeletal, cardiovascular, genitourinary, and central nervous systems. Four previously reported patients had similar break points on chromosome 12 with similar malformations; therefore, phenotype-karyotype correlation suggests a definitive malformation syndrome associated with duplication of chromosome region 12q24.1→qter.     

Mosaic tetrasomy 15q25→qter in a newborn infant with multiple anomalies

We describe a premature boy with metopic craniosynostosis, facial anomalies, atrialseptal defect, hydronephrosis and flexion contractures of lower limbs, and mosaic tetrasomy 15q25→qter. The extra chromosome material was present in the form of an acentric marker. A number of clinical manifestations observed in this child were also found in 3 previously reported patients who were trisomic for the same part of chromosome 15 and in 2 patients who were tetrasomic for a larger segment of 15q. © 1996 Wiley-Liss, Inc.     

Diagnosis of chromosome 3 duplication q23→qter,deletion p25→pter in a patient with the C (trigonocephaly) syndrome

The cells of a deceased patient previously reported to have the C (trigonocephaly) syndrome were reinvestigated because his phenotype resembled that of a patient with a duplication-deficiency of chromosome 3. This diagnosis was confirmed using fibroblasts grown from frozen cells, and his mother was shown to carry an inversion of chromosome 3 in her peripheral blood leukocytes. His findings are compared to those of another patient with the C trigonocephaly syndrome with normal chromosomes and to others from the literature. At least one other patient from the literature has a phenotype compatible with “3q duplication syndrome”.     

Duplication 8q syndrome due to familial chromosome ins(10;8)(q21;q212q22)

We describe a kindred in which an ins(10;8)(q21;q212q22) chromosome rearrangement has been segregating for at least four generations. The risk for balanced carriers to have offspring with duplication of 8q212→8q22 is about 0.31. Individuals with unbalanced chromosomes are mildly to moderately mentally retarded and have a similar unusual appearance. Other manifestations include highly arched or cleft palate (8/9), micrognathia (6/9), sloped shoulders (4–6/9), convulsions (4/9), camptodactyly (3/9), pectus excavatum (2/9), elbow contractures (1/9), and postaxial polydactyly (1/9). The appearance and habitus resemble the mosaic trisomy 8 syndrome, although other anomalies of mosaic trisomy 8, such as vertebral, patellar, and renal defects, were not demonstrated.     

Subtelomeric familial translocation t(2;7)(q37;q35) leading to partial trisomy 7q35→qter: Molecular cytogenetic analysis and clinical phenotype in two generations

Few patients with trisomy of the most distal region of chromosome 7q have been described. We report on a familial translocation t(2;7)(q37;q35) leading to trisomy 7q35→7qter in a child and her paternal uncle and a minimal deletion of distal 2q as demonstrated by FISH with probes located in the chromosome 2q subtelomeric region. The clinical phenotype included macrocephaly and low‐set ears, also found in other reported patients trisomic for the distal part of chromosome 7q. Phenotypic findings probably useful for the clinical diagnosis include normal size at birth, large head with frontal bossing, low‐set ears of normal shape, small nose and low nasal bridge, feeding difficulties in infancy, and severe neurodevelopmental delay. Am. J. Med. Genet. 93:349–354, 2000. © 2000 Wiley‐Liss, Inc.     

Dup(lq)(q42→qter) syndrome: Case report and review of literature

We report on a patient with primordial growth retardation, mental retardation, and minor anomalies (triangular face, open sagittal suture, frontal bossing, telecanthus, upturned nose, micrognathia, and small mouth with downturned corners). The diagnosis of Russell-Silver syndrome (RSS) had been considered but was abandoned when cytogenetic evaluation showed a partial trisomy lq or duplication lq (46,XY,15, + der(15)t(l;15)(q42;qter). Data from another 5 reports of dup(l)(q42→qter) do not allow delineation of a typical syndrome. However, individuals with dup(lq), del(15q), and Russell-Silver syndrome share common manifestations (i.e., low birth weight, growth retardation, triangular face, low set/abnormal ears, micrognathia, renal anomalies). © 1993 Wiley-Liss, Inc.     

Dir dup(X) (q13→qter) in a girl with growth retardation,microcephaly, developmental delay,seizures, and minor anomalies

In males, duplication of a portion of Xq is associated with multiple congenital anomalies and developmental delay. Most females recognized as having dup(Xq) are phenotypically apparently normal relatives of phenotypically abnormal males; phenotypic normalcy has been attributed to selective inactivation of the duplicated X chromosome. Heretofore, apparently only 5 distinctly phenotypically abnormal females with dup(Xq) have been reported. We report on a 3-years-old girl with developmental delay, growth retardation, microcephaly, minor anomalies, and a seizure disorder who had a nonmosaic, de novo direct duplication of the terminal portion of one X chromosome. In each of 50 lymphocytes examined, the duplicated X chromosome was found to be late-replicating. This case shows that selective inactivation (as reflected by late replication) of the duplicated X chromosome does not inevitably confer phenotypic normalcy on females with dup(Xq), and suggests that other mechanisms must account for the phenotypic differences observed among females with dup(Xq), such as expression of recessive genes on the acive X chromosome, incomplete inactivation of some portion of the duplicated inactivation of some portion of the duplicated chromosomal segment, an imprinting effect, or some combination of these. © 1993 Wiley-Liss, Inc.     

Duplication 5q(5q22→5q33): From an intrachromosomal insertion

We report on an infant with an as yet undescribed partial duplication 5q(q22→5q33). He had a number of the already recorded manifestations of partial trisomy 5q, namely microcephaly, growth retardation, brachydactyly, long flat philtrum, thin upper lip vermilion and downturned angles of mouth and apparently low set ears. He survived only 6 months. He inherited his duplication from a maternal intrachromosomal insertion; thus he represents a pure dup(5)(q22→5q33).     

Interstitial Duplication of 7(q22→q34)

We report on a 3-year-old boy with an interstitial duplication of 7(q22→q34), confirmed with fluorescent in-situ hybridization. He had post-natal growth retardation, developmental delay, frontal and parietal bossing, deep-set eyes, strabismus, bilateral optic nerve hypoplasia, and mild dilatation of the cerebral ventricles. His Phenotype was not significantly different from that of the three previously reported patients with interstitial duplication of the smaller segment 7(q22→q31). © 1993 Wiley-Liss, Inc.     

Nonreciprocal and jumping translocations of 15q1→qter in Prader-Willi syndrome

We analyzed 33 cases of Prader-Willi syndrome (PWS) (including 2 personal observations) with translocations of 15q1 → qter onto the terminals of different, apparently whole chromosomes. In all but one of the 23 informative cases the translocations was de novo. Thirty of the patients were unbalanced and 27 had a 45-chromosome constitution compatible with a 3:1 segregation. One balanced and 2 unbalanced translocations were jumping ones. The possible existence of actual non-reciporcal translocations in man is indicated by the following considerations about these and other PWS-associated rearrangements: (1) The observed excess of de novo translocations; (2) the relatively frequent familial occurrence of reciprocal 15q translocations; (3) the concurrence in 3 terminal translocation cases of an idic (15); (4) the visualization of jumping terminal translocations as simple transpositions rather than as successive reciprocal exchanges; (5) the predominance of true isodicentrics in PWS patients with extra inv dup(15) chromosomes; and (6) the rarity of extra derivatives resulting in 15q proximal tertiary trisomy. Additional findings in the present series were normal parental age in the de novo 45-chromosome cases, an apparently random distribution of telomeric breakpoints, and the occurrence of different breakpoints within the 15q1 region.     

Trisomy 1q42→qter in a sister and brother: Further delineation of the “trisomy 1q42→qter Syndrome”

We report on a 22-year-old woman and her 21-year-old brother with mild mental retardation, long face, prominent forehead, retrognathia, and (relative) macrocephaly. At birth they were small for date, their length is now below the 10th centile. Chromosome analysis demonstrated a nearly pure trisomy 1q42→qter in both patients due to unbalanced segregation of a paternal reciprocal balanced translocation 46,XY,t(1;15) (q42;p11). This is the second report of a nearly pure trisomy 1q42→qter. When comparing the manifestations of our patients with those of other reported cases we conclude that the most characteristic clinical manifestations of this syndrome are macrocephaly, prominent forehead, micro/retrognathia, large fontanelle, intrauterine growth retardation, postnatal growth retardation, and mental retardation. © 1995 Wiley-Liss, Inc.     

Atypical phenotype associated with deletion (15) (pter → q11::q13 → qter)

We report on a 10-year-old boy with an interstitial deletion within the region of bands 15q11 → q13. Authors have associated the manifestation of the Prader-Willi syndrome (PWS) with variable deletions involving the bands q11 → q13. Our patient had atypical manifestations not usually associated with PWS, ie, normal stature, proportionally sized hands and feet, normal genitalia, and was nonambulatory and severely mentally retarded. This case emphasized the clinical diversity seen in proximal 15q deletions in the region considered to be correlated with the PWS.     

Partial duplication of 3q (q25.1→q26.1) without the Brachmann-de Lange phenotype

Partial duplications of chromosome 3 have previously been reported to have phenotypic characteristics similar to Brachmann-de Lange syndrome (BDLS). We present the case of a 13-Year-old girl with an apparent duplication in the 3q25.1→q26.1 region but none of the manifestations commonly seen in BDLS. The chromosome 3 duplication was confirmed with a FISH painting probe of the involved region. These results suggest that the region critical for Brachmann-de Lange syndrome is not within the duplicated region of 3q25.1→q26.1. © 1993 Wiley-Liss, Inc.     

Trisomy 6q25→6qter in two sisters resulting from maternal 6;11 translocation

Chromosome banding was used to define a partial duplication of the long arm of chromosome 6 (6q25→6qter) in two profoundly affected sisters and to identify their phenotypically normal mother and sister as balanced translocation carriers whose karyotypes were interpreted as 46,XX,t(6;11) (q25;q25). Prominent clinical features included profound mental retardation, hypertelorism, micrognathia, down-turned mouth, dental anomalies, clubfeet, webbed neck, late progressive scoliosis, flexion contractures, and low total finger ridge count. By comparison with published reports, it has been possible to establish a trisomy 6q25→6qter syndrome.