1/591. child with velocardiofacial syndrome and del (4)(q34.2): another critical region associated with a velocardiofacial syndrome-like phenotype.We report on a child with congenital heart disease (atrial septal defect, ventricular septal defect, pulmonic stenosis), submucosal cleft palate, hypernasal speech, learning difficulties, and right fifth finger anomaly manifestations, consistent with velocardiofacial syndrome (VCFS); however, cytogenetic analysis demonstrated a small terminal deletion of the segment 4q34.2 to 4qter. Fluorescent in situ hybridization did not identify a deletion of the critical region associated with VCFS. In previously reported 4q deletions with a breakpoint distal to 4q34.2, no cardiac defects or cleft of palate were reported. Our patient has a deletion of 4q34.2 to 4qter and has palate and cardiac involvement and minor learning difficulties, which implies that genes involved in heart and palate development lie distal to 4q34.2, and that the critical region for more severe mental retardation on 4q may reside proximal to 4q34.2. These results suggest that a distal 4q deletion can lead to a phenotype similar to VCFS and emphasizes the importance of searching for other karyotype abnormalities when a VCFS-like phenotype is present and a 22q deletion is not identified.- - - - - - - - - - ranking = 1keywords = karyotype (Clic here for more details about this article) |
2/591. Progressive dystonia in a child with chromosome 18p deletion, treated with intrathecal baclofen.We report a case of dystonia with a partial deletion of the short arm (p) of chromosome 18 and androgen insensitivity. Neurologic findings in the 18p syndrome are reported to include mental retardation, seizures, incoordination, tremor, and chorea. A 15-year-old girl with a denovo 18p deletion [karyotype 46, XY, del (18)(p11.1)] developed progressive asymmetric dystonia. She had oromotor apraxia and partial expressive aphasia since childhood, and she was able to partially communicate through elementary sign language. At the age of 15 years, she developed subacute and progressive choreic movements of the right arm, severe dystonic posturing of the left arm, and spastic dystonia in both legs. Her response to parenteral or oral benzodiazepines, oral trihexyphenidyl, benztropine mesylate, baclofen, and L-dopa were brief and inadequate. The response to intrathecal baclofen has been sustained over 18 months. In all likelihood, the 18p deletion syndrome affecting this patient is significant in the pathogenesis of her acquired dystonia. Chronic intrathecal baclofen therapy via pump has been effective in this case and should be considered as a treatment modality in carefully selected patients with dystonia.- - - - - - - - - - ranking = 1keywords = karyotype (Clic here for more details about this article) |
3/591. GATA4 haploinsufficiency in patients with interstitial deletion of chromosome region 8p23.1 and congenital heart disease.Previous studies have shown that patients with deletion of distal human chromosome arm 8p may have congenital heart disease and other physical anomalies. The gene encoding GATA-4, a zinc finger transcription factor implicated in cardiac gene expression and development, localizes to chromosome region 8p23.1. To examine whether GATA-4 deficiency is present in patients with monosomy of 8p23.1 with congenital heart disease, we performed fluorescence in situ hybridization (FISH) with a GATA4 probe on cells from a series of patients with interstitial deletion of 8p23.1. Four individuals with del(8)(p23.1) and congenital heart disease were found to be haploinsufficient at the GATA4 locus by FISH. The GATA4 gene was not deleted in a fifth patient with del(8)(p23.1) who lacked cardiac anomalies. FISH analysis on cells from 48 individuals with congenital heart disease and normal karyotypes failed to detect any submicroscopic deletions at the GATA4 locus. We conclude that haploinsufficiency at the GATA4 locus is often seen in patients with del(8)(p23.1) and congenital heart disease. Based on these findings and recent studies showing that haploinsufficiency for other cardiac transcription factor genes (e.g., TBX5, NKX2-5) causes congenital heart disease, we postulate that GATA-4 deficiency may contribute to the phenotype of patients with monosomy of 8p23.1.- - - - - - - - - - ranking = 1keywords = karyotype (Clic here for more details about this article) |
4/591. Severe mental retardation in a boy with partial trisomy 10q and partial monosomy 2q.A severely mentally subnormal child with many physical stigmata was shown to have the karyotype 46,XY,-2, der(2),t(2;10)(q31;q24)pat. Full evaluation of this patient's karyotype depended on the family studies. It was shown that a balanced translocation t(2,10) was present in 4 normal males in 3 generations.- - - - - - - - - - ranking = 2keywords = karyotype (Clic here for more details about this article) |
5/591. Partial trisomy D: a diagnostic and cytogenetic dilemma.An 18-month-old proposita with psychomotor retardation and other congenital abnormalities is presented. Chromosomal analysis of both parents proved normal. However, the karyotype of the proposita contained 47 chromosomes in both lymphocytes and cultured fibroblasts. The marker chromosome proved to be a deleted No. 14 or 15. Comparison of the reported cases of partial trisomy D indicates that a definitive clinical syndrome is not apparent in either case.- - - - - - - - - - ranking = 1keywords = karyotype (Clic here for more details about this article) |
6/591. Ring 22 duplication/deletion mosaicism: clinical, cytogenetic, and molecular characterisation.A patient with several features consistent with duplication of 22q11.2 (cat eye syndrome or CES) was found to be mosaic for a dicentric double ring chromosome 22 on postnatal karyotyping of peripheral blood. The initial karyotype was 46,XX,r(22)(p12q13) [46]/46,XX,dic r(22)(p12q13; p12q13)[4]. The amount of material duplicated in the dic r(22) was determined to include and extend beyond the CES critical region into 22q13.3. However, karyotyping of lymphocytes and fibroblasts, at 27 and 13 months of age respectively, showed no dic r(22) present in any of the cells examined. We suggest that the CES features in this patient, and potentially in other ring cases with CES phenotypic features, might result from a high level of mosaicism for a dic r(22) during early fetal development. Usually this unstable dic r(22) is subsequently lost from most cells.- - - - - - - - - - ranking = 1keywords = karyotype (Clic here for more details about this article) |
7/591. A de novo deletion of chromosome 15(q15.2q21.2) in a dysmorphic, mentally retarded child with congenital scalp defect.We report a rare chromosomal finding in a boy with a pronounced scalp defect, dysmorphic features and mental retardation. Initially, what seemed to be a normal karyotype by conventional karyotyping was determined to be a de novo deletion involving 15(q15.2q21.2) by high resolution banding. Consequently, prometaphase analysis is warranted in some cases when conventional karyotype analysis appears normal.- - - - - - - - - - ranking = 2keywords = karyotype (Clic here for more details about this article) |
8/591. A locus for isolated cleft palate, located on human chromosome 2q32.We present evidence for the existence of a novel chromosome 2q32 locus involved in the pathogenesis of isolated cleft palate. We have studied two unrelated patients with strikingly similar clinical features, in whom there are apparently balanced, de novo cytogenetic rearrangements involving the same region of chromosome 2q. Both children have cleft palate, facial dysmorphism, and mild learning disability. Their karyotypes were originally reported as 46, XX, t(2;7)(q33;p21) and 46, XX, t(2;11)(q33;p14). However, our molecular cytogenetic analyses localize both translocation breakpoints to a small region between markers D2S311 and D2S116. This suggests that the true location of these breakpoints is 2q32 rather than 2q33. To obtain independent support for the existence of a cleft-palate locus in 2q32, we performed a detailed statistical analysis for all cases in the human cytogenetics database of nonmosaic, single, contiguous autosomal deletions associated with orofacial clefting. This revealed 2q32 to be one of only three chromosomal regions in which haploinsufficiency is significantly associated with isolated cleft palate. In combination, our data provide strong evidence for the location at 2q32 of a gene that is critical to the development of the secondary palate. The close proximity of these two translocation breakpoints should also allow rapid progress toward the positional cloning of this cleft-palate gene.- - - - - - - - - - ranking = 1keywords = karyotype (Clic here for more details about this article) |
9/591. del(6)(q12q15) as the sole cytogenetic anomaly in a case of solitary infantile myofibromatosis.We describe a case of light microscopically typical solitary, infantile myofibromatosis in a 6-month old boy. The myofibroblastic differentiation of the tumor was supported by immunohistochemical and ultrastructural analyses. Cytogenetic and FISH analyses revealed a pseudodiploid karyotype with an interstitial deletion of the long arm of one chromosome 6, del(6)(q12q15), as the sole anomaly. The results demonstrate the usefulness of cytogenetics and FISH in distinguishing this type of lesion from infantile fibrosarcoma. To the best of our knowledge this is the first cytogenetic analysis of solitary infantile myofibromatosis.- - - - - - - - - - ranking = 1keywords = karyotype (Clic here for more details about this article) |
10/591. 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.- - - - - - - - - - ranking = 1keywords = karyotype (Clic here for more details about this article) |
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