Confirmation of proximal 1q duplication using fluorescence in situ hybridization

We report on a boy with excessively wrinkled skin, mild micro/brachycephaly with mild hydrocephalus and slightly small temporal lobes, apparently low-set ears, retro/micrognathia and cleft soft palate (Pierre-Robin anomaly), patent ductus arteriosus and foramen ovale, pulmonary hypoplasia, eventration of the left hemidiaphragm, right cryptorchidism, a sacral dimple, flexion contractures of fingers and knees, and equinovarus deformities of both feet. The infant had a de novo dir dup(1)(pter→ q25::q12→qter). Partial duplications involving proximal 1q have rarely been reported. Furthermore, this is the first case of proximal duplication of chromosome 1q with unequivocal identification using fluorescence in situ hybridization (FISH) with a chromosome 1 painting probe. © 1994 Wiley-Liss, Inc.     

Proximal trisomy of 1q mosaicism in a girl with hypertrophic cardiomyopathy associated with Wolff‐Parkinson‐White syndrome and multiple congenital anomalies

We report an African American female who is mosaic for partial trisomy of 1q due to a direct duplication of 1q12 to 1q25. The child has hypertrophic cardiomyopathy with Wolff‐Parkinson‐White syndrome. The physical features include micrognathia, cleft palate, low set ears, posteriorly placed thumbs, and syndactyly of the second and third toes of both feet. Other abnormalities include intestinal malrotation, scoliosis, mental retardation, cerebral palsy, and hydrocephalus. There was also a selective deficiency of antibody responses to polysaccharide antigens. Proximal duplication of chromosome 1q is rare and has not been previously associated with hypertrophic cardiomyopathy. Most known gene disorders related to hypertrophic cardiomyopathy are autosomal dominant missense mutations in sarcomeric protein genes; however, none of the sarcomeric genes previously linked to hypertrophic cardiomyopathy are in this region. This finding thus highlights the possibility of additional genetic mechanisms for hypertrophic cardiomyopathy. © 2001 Wiley‐Liss, Inc.     

De novo 46,XX, dir dup (11)(q13.3→q14.2) in a patient with mental retardation, congenital cardiopathy and thrombopenia

A 31-year-old female is reported with mild to moderate mental retardation, facial dysmorphy, congenital cardiopathy, and mild thrombocytopenia as the most important clinical findings. Chromosome analysis in lymphocytes showed a de novo dir dup (11)(q13.3→14.2), by both G-banding and FISH techniques. Previously reported constitutional duplications of 11q are mostly the result of unbalanced translocations involving chromosome 11q, and are associated with a partial monosomy or trisomy of the translocation partner chromosome. In case of an unbalanced translocation it is not clear which clinical findings result from the chromosome 11 duplication and which result from the abnormality on the translocation partner chromosome. This is the first report on a constitutional duplication of chromosome region 11q13.3→14.2 without involvement of other chromosomes.     

Properties of associations: Identity,nature, and clinical criteria,with a commentary on why CHARGE and Goldenhar are not associations

We report the use of fluorescent in situ hybridization (FISH) with a DNA library of chromosome 1-specific probes to confirm the karyotype, 46,XY,15, + der15,t(1;15)(q32.1; q26.3), obtained by prenatal periumbilical blood sampling from a fetus who exhibited multiple abnormalities by ultrasound examination. GTG-banding of chromosomes obtained from the mother showed a normal karyotype, while the father was unavailable for study. The propositus was born at 37 weeks gestation and survived for several weeks. Cytogenetic analysis performed after the birth of the male infant with multiple anomalies verified partial trisomy 1q. This patient is compared with other partial trisomy 1q patients reported in the literature. The usefulness of FISH is demonstrated in situations where fetal abnormalities are present with de novo chromosomal rearrangements where paternal chromosomes are unavailable for study. © 1994 Wiley-Liss, Inc.     

Reassessment of a chromosome 12q + marker by fluorescent in situ hybridization (FISH)

We present a case previously described by Jenkins et al. (1983) as atypical Down syndrome (DS). The initial diagnosis was first made on the basis of phenotypic and cytogenetic data. This analysis was supported by studies of superoxide dismutase (SOD1) activity that maps to band 21q22.1. Results from phenotypic, chromosome banding and SODI studies suggested a karyotype of 46,XX,—12, + t(12pter to 12qter::21q21 to 21q22.?2). Using fluorescent in situ hybridization (FISH) for chromosome painting with DNA libraries derived from sorted human chromosomes to stain selectively the chromosomes No. 21 and No. 12, we demonstrate that the marker chromosome 12q+ has no chromosome 21 content but it is derived from chromosome 12.     

Boy with an interstitial 1q (q31q41) duplication confirmed by fluorescent in situ hybridisation

A 20-year-old man with multiple anomalies caused by a de novo duplication of the long arm of chromosome 1 is presented. The patient suffers from severe mental retardation, epilepsy, bronchial stenosis, and minor anomalies (e.g., hirsutism, midface dysplasia, and beaked nose). A G-banding analysis of the patient's chromosomes showed additional segments in chromosome 1. Fluorescent in situ hybridisation analysis with a chromosome 1 painting probe showed that the extra material originated from chromosome 1. Further analysis with cosmid probes demonstrated that the region involving chromosome bands 1q31 to q41 is present in a tandem duplication. Am. J. Med. Genet. 80:163–168, 1998. © 1998 Wiley-Liss, Inc.     

13q部分三体的分子细胞检测及其与斜颈体征的可能关系

目的 探讨斜颈与13号染色体部分三体的可能关系。方法 应用染色体显带技术结合荧光原位杂交确诊两个具有13q部份三体典型临床症状病例的核型，并比较他们的临床表型与已报道病例的异同。结果 两例患者均为13q14→qter的部分三体，尽管另一条衍生染色体不同，但他们都有斜颈临床体征。结论 13q14→qter可能与斜颈相关，结合以前报道过的一篇文献，该基因更精确的定位可能为13q32→qter。     

Trisomy rescue by postzygotic unbalanced (X;14) translocation in a girl with dysmorphic features

In this report we present the clinical features and molecular and cytogenetic findings in a female with partial trisomy 14q. Molecular and cytogenetic studies allowed us to determine that the extra 14q material (of paternal origin) was translocated postzygotically onto the maternal X chromosome. Consequently, only the derivative X chromosome was inactivated, although inactivation apparently did not spread over the entire chromosome 14q. This partial inactivation makes the present case unusual, giving rise to phenotypic features absent in other patients with partial trisomy 14q, typically restricted to the distal part of the chromosome.     

Tandem duplication mosaicism: characterization of a mosaic dup(5q) and review

Mosaicism for tandem duplications is rare. Most patients reported had abnormal phenotypes of varying severity, depending on the chromosomal imbalance involved and the level of mosaicism. Post-zygotic unequal sister-chromatid exchange has been proposed as the main mechanism for tandem duplication mosaicism. However, previous molecular analyses have implicated both meiotic and post-zygotic origins for the duplication. We describe a newborn male who was originally diagnosed in utero with arrhythmia and tetralogy of Fallot. He had multiple dysmorphic features including telecanthus, blepharophimosis, high broad nasal bridge with a square-shaped nose, flat philtrum, thin upper lip, down-turned corners of the mouth, high-arched palate, micrognathia, asymmetric ears, and long, thin fingers and toes. Karyotyping of peripheral blood lymphocytes showed mosaicism for a tandem duplication of part of the long arm of one chromosome 5: mos46,XY,dup(5)(q13q33)[6]/46,XY[45]. Fibroblast cultures had the same mosaic karyotype with a higher frequency of the dup(5) clone: mos46,XY,dup(5)(q13q33)[9]/46,XY[21]. Fluorescence in situ hybridization analysis with a wcp5 confirmed the chromosome 5 origin of the additional material. Parental karyotypes were normal indicating a de novo origin of the dup(5) in the proband. Molecular analyses of chromosome 5 sequence-tagged-site (STS) markers in our family were consistent with a post-zygotic origin for the duplication. Therefore, mosaicism for tandem duplications can arise both through meiotic or mitotic errors, as a result of unequal crossing over or unequal sister-chromatid exchange, respectively. Our review indicates that mosaicism for tandem duplications is likely under-ascertained and that parental karyotyping of probands with non-mosaic tandem duplications should be performed.     

Proximal duplication of the long arm of chromosome 10 (10q11.2 → 10q22): a distinct clinical entity

This report summarizes the clinical and cytogenetic findings in a 16-year-old moderately mentally retarded girl with 10q11.2----10q22 duplication. The phenotypic findings are identical to those found in one other patient with the same autosomal duplication. These data suggest that proximal 10q11.2-10q22 duplication is associated with a specific clinically recognizable syndrome.     

Dysmorphic features and learning disability in an adult male with pure partial trisomy 17q24‐q25 due to a terminal duplication

We describe an adult male with severe learning disability, epilepsy, and dysmorphic features. Cytogenetic studies demonstrated a terminal duplication of the long arm of chromosome 17, resulting in partial trisomy 17q24‐q25. Our patient shows some of the characteristic features of the distal 17q phenotype, but in addition has more unusual features such as epilepsy, sensorineural hearing loss, and long fingers and overlapping toes. We suggest that these features occur with terminal duplications of 17q. © 2002 Wiley‐Liss, Inc.     

Molecular cytogenetic characterisation of partial trisomy 9q in a case with pyloric stenosis and a review

Partial trisomy 9q represents a rare and heterogeneous group of chromosomal aberrations characterised by various clinical features including pyloric stenosis. Here, we describe the case of a 1 year old female patient with different dysmorphic features including pyloric stenosis and prenatally detected partial trisomy 9q. This partial trisomy 9q has been analysed in detail to determine the size of the duplication and to characterise the chromosomal breakpoints. According to the data gained by different molecular cytogenetic techniques, such as fluorescence in situ hybridisation (FISH) with whole and partial chromosome painting probes, yeast artificial chromosome (YAC) probes, and comparative genomic hybridisation (CGH), the derivative chromosome 9 can be described as dup(9)(pter→q22.1::q31.1→q22.1::q31.1→ q22.1::q31.1→qter). Four breakpoint spanning YACs have been identified (y806f02, y906g6, y945f5, and y747b3) for the proximal breakpoint. According to this new case and previously published data, the recently postulated putative critical region for pyloric stenosis can be narrowed down to the subbands 9q22.1-q31.1 and is the result of either partial trisomy of gene(s) located in this region or a gene disrupted in 9q31.


Keywords: partial trisomy 9q; pyloric stenosis; FISH; CGH     

11q trisomy detected by fluorescence in situ hybridization

Takano T, Yamanouchi Y, Kawashima S, Date M, Hashira S, Kida M, Abe T, Nakahori Y, Nakagome Y. 11q trisomy detected by fluorescence in situ hybridization. Clin Genet 1993: 44: 324–328. © Munksgaard, 1993 A patient with psychomotor developmental delay, multiple minor anomalies, congenital heart disease and left inguinal hernia is reported. His karyotype was 45,X/46,X,+mar (3 : 37 cells), and the marker chromosome was identified as t(Y;11) (q12;q14?) using fluorescence in situ hybridization and fluorescent chromosome painting. He was diagnosed as mosaic for de novo 11q trisomy.     

Proximal 5p trisomy resulting from a marker chromosome implicates band 5p13 in 5p trisomy syndrome

We describe an infant with trisomy of (5)(p10p13.1) resulting from a de novo marker chromosome. The marker's origin was identified by chromosome microdissection and reverse in situ hybridization. The clinical findings are compared to those of other partial and complete 5p duplications. This case further defines the critical region of 5p trisomy syndrome to proximal 5p. Am. J. Med. Genet. 87: 6–11, 1999. © 1999 Wiley-Liss, Inc.     

Partial trisomy 1 (q42→ter)

Clinical findings on three closely related, severely malformed infants and a 20-week-old fetus with an identical partial trisomy of chromosome 1 (1q42→ter) have made possible the delineation of a new syndrome. The typical manifestations of this syndrome are: severe intrauterine and postnatal developmental retardation, trigonocephaly with wide sutures and fontanels, characteristic facial features, colobomata of the iris, small hands and feet, and early death.     

Clinical and molecular cytogenetic characterization of two patients with partial trisomy 1q41‐qter: Further delineation of partial trisomy 1q syndrome

We report the clinical and molecular cytogenetic characterization of two patients with partial trisomy 1q. The first patient is a currently 11‐year‐old female proposita with a de novo unbalanced translocation 46,XX,der(8)(8qter‐8p23.3::1q41‐1qter), leading to a partial trisomy 1q41‐qter and a partial monosomy for 8p23.3‐pter. The most prominent clinical features of the girl are a triangular face, almond‐shaped eyes, low‐set ears, short stature with relatively long legs, and mild psychomotor retardation. To our knowledge, the cytogenetic aberration in this girl is the most proximal partial trisomy 1q leading to a mild phenotype. Recently, we identified a second patient with a similar partial trisomy 1q combined with a cri du chat syndrome caused by a de novo unbalanced translocation 46,XX,der(5)(5qter‐5p13.1::1q41‐1qter). Comparison of the phenotype of the two girls as well as with already published trisomy 1q cases was performed, and fluorescence in situ hybridization probes from selected YACs were used to delineate the extent of the partial trisomy in more detail. © 2001 Wiley‐Liss, Inc.     

Segregation of a paternal insertional translocation results in partial 4q monosomy or 4q trisomy in two siblings

A genetics evaluation was requested for a 6-week-old infant with multiple congenital malformations including mild craniofacial anomalies, truncal hypotonia, hypospadias, and a ventriculoseptal defect. Blood obtained for chromosome analysis revealed an abnormal chromosome 4. Paternal chromosome analysis showed a 46,XY, inv ins (3;4) (p21.32; q25q21.2), inv(4)(p15.3q21.2) karyotype. Therefore, the proband's chromosome 4 was the unbalanced product of this insertional translocation from the father resulting in partial monosomy 4q. Additionally, the derivative 4 had a pericentric inversion which was also seen in the father's chromosome 4. During genetic counseling, the proband's 2-year-old brother was evaluated. He was not felt to be abnormal in appearance, but was described as having impulsive behavior. Chromosome analysis on this child revealed 46,XY,der(3)inv ins(3;4)(p21.32;q25q21.2)pat. This karyotype results in partial trisomy 4q. FISH using two-color “painting” probes for chromosomes 3 and 4 confirmed the G-banded interpretation in this family. The segregation seen in this family resulted in both reciprocal products being observed in the two children, with partial 4q monosomy showing multiple congenital anomalies, and partial 4q trisomy showing very few phenotypic abnormalities. © 1995 Wiley-Liss, Inc.