A report of a child with a deletion (9)(q34.3): a recognisable phenotype?

We report a case of a male infant who presented with congenital anomalies and was found to have a de novo deletion in the terminal region of the long arm of chromosome 9. He died at the age of 17 weeks of cardiorespiratory failure owing to RSV positive bronchiolitis. A review of previously published reports documented one previous report of a patient with a deletion of (9)(q34.3) and multiple congenital anomalies. Comparison with the previously reported case suggests that the phenotype observed constitutes a clinically recognisable pattern of malformations.     

Terminal deletion of 7q presenting in utero with a truncus arteriosus and nonimmune hydrops

Terminal deletion of 7q presents with variable anatomical and developmental findings. This case is the first reported in utero diagnosis based on cytogenetic findings and in utero demonstration of resolving congestive heart failure due to a truncus arteriosus. © 1993 Wiley-Liss, Inc.     

Monosomy 18q syndrome and atypical Rett syndrome in a girl with an interstitial deletion (18)(q21.1q22.3)

We describe a 6 1/2-year-old girl with an interstitial deletion of chromosome arm 18q (18q21.1q22.3). Her clinical manifestations are a combination of those found in monosomy 18q syndrome and those of Rett syndrome. Cytogenetic analysis demonstrated a deletion of the long arm of chromosome 18, defined by molecular analysis with polymorphic markers as a de novo interstitial deletion, paternally derived. The findings typical of the 18q- syndrome included mental retardation, midface hypoplasia, and hypoplasia of labia majora, and those typical of Rett syndrome were severe mental retardation, autistic behavior, inappropriate hand-washing movements, epilepsy, attacks of sighing and hyperventilation, and progressive scoliosis since the age of 5 years. She did not have microcephaly, and the mental delay was obvious from an early age without a period of normal development, which makes the diagnosis of Rett syndrome atypical. Previously, a girl with mosaicism for a monosomy 18q associated with Rett syndrome has been described. That girl had a terminal deletion of chromosome 18q, which seems to coincide in part with that in the present girl. It is possible that genes in the distal region of 18q are involved in the etiology of Rett syndrome.     

De novo interstitial deletion of the long arm of chromosome 3:46, XX, del(3) (q25.1q26.1)

Robin NH, Magnusson M, McDonald-McGinn D, Zackai EH, Spinner NB. De novo interstitial deletion of the long arm of chromosome 3: 46,XX,del(3) (q25.1q26.1). Clin Genet 1993: 44: 335–337. © Munksgaard, 1993
A girl with an interstitial deletion of chromosome 3 is presented. The facial resemblance to an earlier reported patient with a shared breakpoint is addressed.     

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.     

Holoprosencephaly in an infant with a minute deletion of chromosome 21(q22.3)

We evaluated an infant because holoprosencephaly had been detected by prenatal ultrasound examination and magnetic resonance imaging (MRI). Postnatally, high-resolution cytogenetic studies showed a minute deletion of chromosome 21(q22.3). This patient lacks many of the characteristics associated with monosomy 21, partial monosomy 21, and ring 21 chromosome patients. She also lacks the midline facial abnormalities often seen with holoprosencephaly. The similarity in facial appearance between this case and one previously reported patient with holoprosencephaly and a ring chromosome 21 suggests a causal relationship between holoprosencephaly and deletion of chromosome 21(q22.3). These findings also suggest that infants and children with developmental delay and apparently normal facial appearance should be examined for holoprosencephaly and that all identified patients with holoprosencephaly need high-resolution cytogenetic studies with careful attention to the terminal portion of 21q.     

Additional case of de novo interstitial deletion del(17)(q21.3q23) and expansion of the phenotype

Khalifa MM, MacLeod PM, Duncan AMV. Additional case of de novo interstitial deletion del(17)(q21.3q23) and expansion of the phenotype. Clin Genet 1993: 44: 258–261. © Munksgaard, 1993
A child with multiple congenital abnormalities and a de novo interstitial deletion of the long arm of chromosome 17 is reported. This is the third case reported with this chromosome abnormality. The three cases present a peculiar phenotype, which is probably specific to the deletion.     

A case of deletion 14(q22.1-->q22.3) associated with anophthalmia and pituitary abnormalities.

An interstitial deletion of the region q22.1-->q22.3 of chromosome 14 is described in a child with bilateral anophthalmia, dysmorphic features including micrognathia, small tongue, and high arched palate, developmental and growth retardation, undescended testes with a micropenis, and hypothyroidism. Interstitial deletions of the long arm of chromosome 14 are extremely rare, but this case seems to confirm that the region q22 is specifically concerned with pituitary and eye development.     

Duplication 2 (q11.2-q21): a previously unreported abnormality

A 7 year old boy is described with moderate learning disability, facial dysmorphism, and a de novo duplication of chromosome 2 (q11.2-q21). There are few published reports of proximal 2q duplication, and none reporting direct de novo duplication for this exact region.     

A case of de novo interstitial deletion 3q.

A rare chromosome abnormality consisting of interstitial deletion 3q was found in a malformed girl. Chromosome analysis using G and Q banding showed deletion of bands 3q12----3q21: 46,XX,del(3)(pter----q12::q21----qter). The clinical features of the proband included severe psychomotor retardation, craniofacial asymmetry, hypertelorism, epicanthus, high arched palate, progressive scoliosis, multiple skin pigmentations, and renal abnormalities. The parents had normal karyotypes.     

Developmental delay and facial dysmorphism in a child with an 8.9 Mb de novo interstitial deletion of 3q25.1-q25.32: Genotype-phenotype correlations of chromosome 3q25 deletion syndrome

Interstitial deletions of the long arm of chromosome 3 are rare and detailed genotype-phenotype correlations are not well established. We report on the clinical, cytogenetic and molecular findings of a 5-year-old patient with a de novo interstitial deletion from 3q25.1 to 3q25.32. Clinical features include relative microcephaly, developmental delay and facial dysmorphism with a coarse face, ptosis, synophrys, epicanthic folds, broad nasal bridge, long philtrum, large mouth with full lips, dysplastic and low-set ears. Revealed by conventional banding techniques, the deleted region of 8.9?Mb was confirmed by fluorescent in situ hybridization (FISH) analyses and array comparative genomic hybridization (array-CGH). To our knowledge, this is the smallest interstitial deletion reported in the 3q25 region. The phenotype of our patient is compared with the 10 previously reported cases implicating the 3q25 region.     

Delineation of an interstitial 9q22 deletion in basal cell nevus syndrome

Basal cell nevus syndrome (Gorlin syndrome) is an autosomal dominant disorder characterized by the presence of multiple basal cell carcinomas (BCC), odontogenic keratocysts, palmoplantar pits, and calcification in the falx cerebri caused by mutational inactivation of the PTCH gene. In few cases, the syndrome is due to a microdeletion at 9q22. Using high-resolution chromosome analysis we have identified a patient with the karyotype, 46,XY,del(9)(q21.3q31) de novo. He had typical clinical features consistent with basal cell nevus syndrome, but also additional features likely to be caused by loss of additional chromosomal material in this region. The deletion breakpoints were characterized with fluorescence in situ hybridization (FISH) analysis using BAC clones. The 15 Mb long deletion includes 87 RefSeq genes including PTCH. Hemizygosity of one or more genes might contribute to the additional symptoms observed in this patient.     

A case of de novo interstitial deletion of chromosome 5(q33q34)

The present paper describes a girl with a small de novo deletion of chromosome 5(q33q34). Fluorescence in situ hybridisation with locus specific probes was used to define the extent of this deletion. Clinical features in this patient are microcephaly, dysmorphic facial features such as epicanthus, small biparietal distance and retrognathia, four-finger lines on both hands and mild mental retardation.     

Molecular cytogenetic analysis of a familial interstitial deletion Xp22.2-22.3 with a highly variable phenotype in female carriers

We describe a familial interstitial deletion of 7.7-Mb involving Xp22.2-22.3. The deletion was transmitted from an asymptomatic mother to her two children with severe developmental delay, no speech development and autistic behavior. Assessment of the deletion boundaries by FISH and PCR analyses indicated that the deletions encompasses 27 genes. Several of these genes are associated with known disorders, like KAL1 (Kallmann syndrome), steroid sulfatase (STS) (X-linked ichtyosis), and arylsulfatase E (ARSE) (chondrodysplasia punctata). The deletion also includes all four VCX genes (VCX-A, VCX-B1, VCX-B, and VCX-C) and the neuroligin 4 (NLGN4) gene. VCX-A deficiency has been shown previously to be associated with mental retardation and NLGN4 mutations lead to mental retardation in conjunction with autism. Functional deficiency of both MRX genes, VCX-A and NLGN4, are most likely associated with the impaired cognitive development of the patients described here. The phenotype associated with the Xp deletion was highly variable in female carriers and might be attributed to unfavorable X inactivation. However, all the 27 genes included in the deleted interval escape X inactivation and are expressed at variable levels from the normal X chromosome. Thus, the overall X inactivation pattern and inter-individual expression variability of the genes in distal Xp might be determinants of the phenotype associated with the deletion.     

Molecular cytogenetic characterization of an interstitial deletion of chromosome 21 (21q22.13q22.3) in a patient with dysmorphic features, intellectual disability and severe generalized epilepsy

We report on a de novo interstitial deletion of chromosome 21q in a patient presenting with characteristic facial features, intellectual disability, and epilepsy. The deletion extent was about 4.9 Mb from position 37713441 bp (21q22.13) to position 42665162 bp (21q22.3) (NCBI36/hg18 map).Patients with partial monosomy 21 are quite rare; this anomaly has been associated with a wide spectrum of clinical signs, ranging from very mild to quite severe phenotypes. This variability results from variability in the deleted regions, thus accurate molecular definition of the chromosomal breakpoints is necessary to make better genotype-phenotype correlations.We compared our patient's phenotype with the few other patients reported in the literature and found to have similar deletion when analyzed by array CGH. The minimal overlapping region contains only two genes, DYRK1A and KCNJ6, which may play a major role in these patients' phenotype.     

Adult with an interstitial deletion of chromosome 10 [del(10)(q25.1q25.3)]: Overlap with Coffin‐Lowry Syndrome

We recently evaluated a mentally retarded 48 year old man found to have a cytogenetic deletion of chromosome 10 [46,XY,del(10) (q25.1q25.3)]. Of interest, he shares many clinical findings with those described in Coffin‐Lowry syndrome (CLS). These include severe mental retardation, short stature and a coarse facial appearance with widely spaced eyes, and patulous lips. He also had an extra transverse hypothenar crease, a finding that is seen in CLS. Furthermore, he has characteristic radiographic hand findings described in 95% of patients with CLS. The CLS gene, located at Xp22.2, has recently been identified, and mutations in the Rsk‐2 gene have been identified in several CLS patients. Rsk2 is part of a gene family implicated in cell cycle regulation through the mitogen‐activated protein (MAP) kinase cascade. None of the currently recognized components of this pathway maps to the region deleted in our patient, nor are we able to identify any likely candidate genes in the deleted region, although several G protein coupled receptors have been cloned from the region. This patient's findings have some overlap with those seen in CLS, suggesting that a gene involved in MAP kinase signaling may be present in the deleted region of chromosome 10q25.1‐25.3. Patients with a phenotype consistent with CLS, but lacking a family history suggestive of an X‐linked disorder, should be evaluated with chromosome analysis paying particular attention to the region 10q25. Am. J. Med. Genet. 95:93–98, 2000. © 2000 Wiley‐Liss, Inc.     

Blepharophimosis,ptosis, and epicanthus inversus syndrome (BPES) associated with interstitial deletion of band 3q22: Review and gene assignment to the interface of band 3q22.3 and 3q23

We report on a child with blepharophimosis, ptosis, and epicanthus inversus (BPES), developmental delay and an interstitial deletion of band q22 of chromosome 3. A review of chromosome 3q anomalies associated with eye abnormalities, specifically blepharophimosis and ptosis, strongly suggests that a locus for eyelid development is present at the interface of bands 3q22.3 and 3q23. © 1993 Wiley-Liss, Inc.