1/15. 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 = 1keywords = karyotype (Clic here for more details about this article) |
2/15. Case of partial trisomy 2q3 with clinical manifestations of Marshall-Smith syndrome.We describe a girl with physical anomalies, accelerated skeletal maturation, failure to thrive, and respiratory difficulties consistent with a diagnosis of Marshall-Smith syndrome (MSS). Chromosome analysis showed an inverted duplication of chromosome 2 [46,XX,inv dup(2)(q37q32) de novo] identified by G banding and confirmed by FISH. Several cases of trisomy 2q3 have been reported and established a syndrome, but the present case is the first to be associated with accelerated skeletal maturation and a clinical picture resembling MSS. This raises the possibility that the cause of MSS involves the q3 region of chromosome 2. Few reports of MSS include study of the karyotype, although the chromosomes were apparently normal in those cases where they have been examined. We suggest that karyotyping be undertaken with particular attention to the 2q3 region in patients with suspected MSS. It also would be prudent to assess bone age in all children with trisomy 2q.- - - - - - - - - - ranking = 0.5keywords = karyotype (Clic here for more details about this article) |
3/15. Detection of a cryptic translocation t(13;20)(q34;p13) in an unexplained case of MCA/MR: value of FISH over high resolution banding.Cryptic unbalanced chromosome rearrangements in the telomeric bands of the chromosomes may constitute a significant cause of unexplained mental retardation with or without congenital anomalies. We report on a boy with a terminal deletion of the long arm of chromosome 13, combined with a partial duplication of the short arm of chromosome 20, owing to a cryptic balanced translocation in his father. The karyotype of the father was 46XY,t(13;20)(q34;p13). The propositus presented with severe mental and growth retardation, microcephaly, facial anomalies including ptosis of the right upper eyelid, a high nasal bridge, small palpebral fissures, and bilateral epicanthus, hypospadias, and scoliosis. A younger brother died at birth and had a low birth weight, hypospadias, and a horseshoe kidney. Repeated chromosome analyses with high resolution banding in the propositus and his parents were apparently normal. chromosome painting eventually disclosed the cryptic translocation in the father with unbalanced karyotype in the propositus. The importance of additional FISH analysis in patients with unexplained mental retardation, physical anomalies, and apparently normal chromosomes is emphasized.- - - - - - - - - - ranking = 1keywords = karyotype (Clic here for more details about this article) |
4/15. Identification of supernumerary marker chromosomes derived from chromosomes 5, 6, 19, and 20 using FISH.A large number of cases with supernumerary marker chromosomes (SMCs) should be compared to achieve a better delineation of karyotype-phenotype correlations. Here we present four phenotypically abnormal patients with autosomal marker chromosomes analysed by fluorescence in situ hybridisation using centromeric, telomeric, and unique sequence probes, as well as forward and reverse painting. We also report the first case, to the best of our knowledge, of an SMC derived from chromosome 5. Furthermore, a marker chromosome 20 in a patient with sex differentiation abnormalities, a double mar(6) in a boy with psychomotor retardation, and the association of r(19) with dup(21q21.2q22.12) are described. Although the mar(6) was very small, the presence of euchromatin was shown, suggesting that the partial trisomy of pericentric region derived sequences is implicated in the aetiology of the abnormal phenotypes.- - - - - - - - - - ranking = 0.5keywords = karyotype (Clic here for more details about this article) |
5/15. Deletion (9) (p13.1 p21.1).We report on a 22-month-old girl with minor facial anomalies, global developmental delay, growth retardation, seizures, and leukoencephalopathy. Initial clinical assessment suggested the diagnosis of williams syndrome. Results of fluorescence in situ hybridization testing for elastin were normal. However, chromosome analysis showed a 46,XX,del(9)(p13.1p21.1) karyotype in peripheral lymphocytes. Parental chromosomes were normal, indicating a de novo deletion. This patient's manifestations are compared with those of two other cases with overlapping deletions of the proximal short arm of chromosome 9.- - - - - - - - - - ranking = 0.5keywords = karyotype (Clic here for more details about this article) |
6/15. A patient with 2 different repeat expansion mutations.BACKGROUND: Many inherited progressive encephalopathies have a poor outcome, and some are caused by repeat expansion mutations. How would the presence of 2 different expansion mutations affect the phenotype? OBJECTIVE: To describe a patient who has 2 distinct, rare genetic disorders: myotonic dystrophy (DM, OMIM 160900) and progressive myoclonus epilepsy of the Unverricht-Lundborg type (EPM1, OMIM 254800). Both conditions are caused by repeat expansion mutations. They affect the central nervous system causing mental retardation, but also produce a wide spectrum of disabilities in daily living. SETTING: Referral center. methods: Clinical description with accompanying photographs, electroencephalography and magnetic resonance imaging; dna analysis of both of the mutations and chromosomal analysis with prometaphase spreads. RESULTS: The patient had clinical characteristics and findings of both myotonic dystrophy and progressive myoclonus epilepsy of the Unverricht-Lundborg type. Electroencephalographic recordings over a 3-year period showed typical findings for myoclonus epilepsy. The patient had no gross anomalies in brain magnetic resonance imaging. She had a normal karyotype, and both of the diagnoses were confirmed at the molecular level with the direct detection of the mutations. CONCLUSIONS: Despite having 2 different progressive inherited disorders affecting the central nervous system, the patient, at age 28 years, showed only mild mental retardation with very slow progression. However, clear deterioration in activities of daily living has taken place during last 3 years. Arch Neurol. 2000;57:1199-1203- - - - - - - - - - ranking = 0.5keywords = karyotype (Clic here for more details about this article) |
7/15. dystonia in a patient with deletion of 18p.18p- syndrome from chromosomal deletion of the short arm of chromosome 18 shows a wide range of clinical manifestations. Mental retardation is the most frequent neurological complication; other neurological deficits are more rarely reported. Only one 18p- patient with focal dystonia at the lower limbs has been reported, while there have been no reported cases of generalized dystonia. We report a 27-year-old male with 18p- de novo complete deletion (karyotype 46,XY,18p-) who was affected by severe generalized dystonia, hypokinesia, mental retardation and dysmorphic features. The 18p- syndrome should be added to the list of genetic causes of secondary dystonia. A karyotype analysis should be considered in secondary dystonias, particularly when there are associated dysmorphic features and mental retardation.- - - - - - - - - - ranking = 1keywords = karyotype (Clic here for more details about this article) |
8/15. Wolf-Hirschorn syndrome resulting from partial monosomy 4p/trisomy 9p.An infant girl was referred for a genetic consultation because of facial appearance suggestive of Wolf-Hirschorn syndrome (WHS), growth retardation and generalized hypotonia. She had an unbalanced karyotype 46,XX,der(4)t(4;9)(p15.2;p22)mat resulting in the deletion of the critical region for WHS and duplication of the critical region for the 9p duplication syndrome. The mother and the grandmother of proposita were the carriers of an apparently balanced translocation 46,XX,t(4;9)(p15.2;p22). The infant's phenotype was characteristic of WHS syndrome rather than that of duplication 9p phenotype. This is probably the first description of WHS phenotype resulting from a familial 4;9 translocation.- - - - - - - - - - ranking = 0.5keywords = karyotype (Clic here for more details about this article) |
9/15. VATER--tibia aplasia association: report on two patients.We report two patients with oesophageal atresia, tracheo-oesophageal fistula and unilateral tibial aplasia. The karyotype in both patients was normal and both cases were sporadic. The congenital defects of the children can be regarded as an uncommon variant of VA(C)TER(L) association. Recently Basel and Goldblatt [(2000) Clin Dysmorphol 9:205-208] reported a similar patient with a VATER-tibia aplasia association.- - - - - - - - - - ranking = 0.5keywords = karyotype (Clic here for more details about this article) |
10/15. Molecular cytogenetic characterization of a de novo unbalanced translocation leading to trisomy 17q25-->qter and monosomy 18p11.3-->pter in a girl with dysmorphic features.An 18-year-old, gravida 1 underwent percutaneous umbilical blood sampling (PUBS) because of positive triple screen, oligohydramnios and markedly short fetal bones. Chromosome analysis showed an abnormal chromosome 18 with unidentified chromatin at the end of the p-arm. Parental karyotypes were normal. FISH analyses with wcp18 showed additional material of unknown origin on the derivative chromosome 18. Further FISH analysis with subtelomeric probes showed normal signals for the long arm of chromosome 18 (18q23) while no signals were observed for the short arm (18p11.32). These findings were confirmed using a YAC probe from the short arm of 18. The infant was delivered at 30 weeks of gestation. At age 3 months, she was developmentally delayed and has multiple dysmorphic features. Further molecular cytogenetic studies including M-FISH and subtelomere probes showed that the additional material on chromosome 18 consisted of the distal 17q25-->qter region. Based on these studies the karyotype has been interpreted as 46,XX,der(18)t(17;18)(q25;p11.32). To the best of our knowledge, this is the first report of partial monosomy 18p and partial trisomy 17q in a patient with no major CNS malformations. This case shows the importance of molecular cytogenetic techniques in detailed characterization of de novo chromosome rearrangements.- - - - - - - - - - ranking = 1keywords = karyotype (Clic here for more details about this article) |
| | Next -> |