1/44. A microdeletion syndrome due to a 3-Mb deletion on 19q13.2--diamond-Blackfan anemia associated with macrocephaly, hypotonia, and psychomotor retardation.We report on a boy with congenital pure red blood cell aplasia [diamond Blackfan anemia (DBA)] and severe congenital hypotonia, macrocephaly, hypertelorism, a broad and tall forehead, medial epicanthus, and facial hypotonia with mouth-breathing and drooling, an affable and out-going personality, and a general psychomotor retardation. These features show similarity to the phenotype of the X-linked FG syndrome. DBA was diagnosed at the age of 4 months, and the boy underwent treatment with transfusion and with prednisolone. He had a normal 46, XY karyotype, but fluorescence in situ hybridization (FISH) analysis to metaphase chromosomes revealed a 3-Mb deletion on 19q13.2. This chromosomal region has previously been linked to the DBA phenotype and one 19q13 microdeletion has been identified in a patient with DBA. This deletion coincides with the deletion reported here. We suggest that the complex phenotype of our patient, including both DBA and the associated features, represent a microdeletion syndrome.- - - - - - - - - - ranking = 1keywords = karyotype (Clic here for more details about this article) |
2/44. trisomy iop. A report of two cases due to a familial translocation rcp (10;21) (pII;pII).trisomy for the short arm of chromosome number 10 was diagnosed (by a G-banding method) in two sisters with multiple congenital defects. Their mother and two other sisters showed a balanced translocation 46,XX rcp(10;21)(p11;p11), so the affected girls were the result of a maternal adjacent-1 meiotic segregation with a karyotype 46,XX, der(21), rcp(10;21)(p11;p11)mat. The concordant features in the abnormal patients constitute the following syndrome: severe psychomotor retardation, congenital microsomatia, mild hydrocephalus with cranium-face disproportion, low set ears with hypoplastic helix, ocular colobomata, pulmonary stenosis,flexion deformity of wrists and elbows, bilateral fifth finger clinodactyly and simian creases, hypoplastic dermal ridges, bilateral talipes, persistent icterus and delayed bone age. The phenotypical and cytogenetic findings permit the individualization of the 10p trisomy.- - - - - - - - - - ranking = 1keywords = karyotype (Clic here for more details about this article) |
3/44. The 12p trisomy syndrome.trisomy for the short arm of chromosome number 12 was diagnosed (by a G-banding method) in a girl with multiple congenital defects. Her mother and two sisters showed a balanced translocation 46,XX,rcp(12;21)(p11;p11), so, the affected girl was the result of a maternal adjacen t-1 meiotic segregation with a karyotype 46,XX,der21,rcp(12;12)(p11;q11)mat. Another sister decreased at 3 yr of age showed similar phenotypical features and was considered also affected although no karyotype studies were performed. Both affected cases were compared with a previous one and the concordant characteristics allowed the individualization of the following syndrome: severe mental retardation, peculiar flat facies with prominent checks, epicanthic folds, broad and irregular implantation of the eyebrows, broad and flat nasal bridge with short and narrow nose, anteverted nostrils and large philtrum, broad and prominent lower lip, low set ears with folded helix, prominent anthelix and deep concha, "spade" shape fingers (sharp-pointed distal phalanges) with shortness of the fifth, bilateral genu valgum, slightly increased space between first and second toes, secral dimple, generalized hypotonia and hyporeflexia of knees and ankles, nistagmus, retarded and dysrythmic bone age, simian creases or equivalent and distal axial triradii.- - - - - - - - - - ranking = 2keywords = karyotype (Clic here for more details about this article) |
4/44. phenotype of a patient with pure partial trisomy 2p(p23-->pter).We present the case of a 7-month-old girl with the karyotype 46,XX, der(13) t(2;13)(p23;p11.2).ish der(13)(wcp2 ) de novo. Painting confirmed that the additional segment on 13p was of chromosome 2 origin, resulting in trisomy 2p23 -->2pter. The child had a prominent forehead with a flat hemangioma, depressed nasal bridge, protruding tongue, posteriorly angulated ears, esotropia with poor abduction of the right eye, bilateral severe myopia (-5.5 D), retinal hypopigmentation, foveal hypoplasia, and striking left optic nerve hypoplasia. She also had pectus excavatum, a protruding abdomen with diastasis recti, generalized hypotonia, delayed fine and gross motor development, grade II reflux on the left side, and grade III-IV reflux on the right side. An EEG showed epileptiform discharges. Computed tomographic scan of the brain showed decreased white matter, but magnetic resonance imaging showed normal results.- - - - - - - - - - ranking = 1keywords = karyotype (Clic here for more details about this article) |
5/44. Maternal UPD 20 in an infant from a pregnancy with mosaic trisomy 20.Maternal uniparental disomy (UPD) 20 was found in a 35-month-old girl, the product of a pregnancy complicated by a prenatal diagnosis of mosaic trisomy 20. Phenotypic abnormalities included pre- and postnatal growth failure, microcephaly, minor dysmorphic features and psychomotor developmental delay. Chromosomal analysis on cord blood revealed only a normal 46,XX karyotype. Microsatellite analysis of 27 chromosome 20 loci confirmed maternal UPD for all 11 informative markers. Maternal heterodisomy was detected in two and maternal isodisomy in three loci. In the remaining six loci, a non-informative maternal UPD pattern was displayed, as mother and proband are homozygous for the same allele. To our knowledge this is the first reported case of maternal disomy 20 with normal karyotype ascertained by a mosaic trisomy 20 pregnancy.- - - - - - - - - - ranking = 2keywords = karyotype (Clic here for more details about this article) |
6/44. Deletion of chromosome region 18q21.1 --> 18q21.3 in a patient without clinical features of the 18q- phenotype.In a 16-month-old boy referred because of developmental delay and asymmetric motor development, chromosome analysis showed an aberrant chromosome 18 in all 25 metaphases examined. The chromosome aberration was initially interpreted either as an interstitial deletion of chromosome region 18q21.1 --> 18q21.3 or an unbalanced translocation involving the distal part of the long arm of chromosome 18. Chromosome microdissection in combination with fluorescence in situ hybridization demonstrated that the aberrant chromosome 18 had an interstitial deletion, the karyotype being: 46,XY,del(18)(q21.1q21.3). At age 27 months, his development was moderately retarded. He showed craniofacial asymmetry but no other anomalies. The clinical and cytogenetic findings are compared with previously reported patients with a terminal or interstitial deletion in the long arm of chromosome 18.- - - - - - - - - - ranking = 1keywords = karyotype (Clic here for more details about this article) |
7/44. Mosaic supernumerary inv dup(15) chromosome with four copies of the P gene in a boy with pigmentary dysplasia.association of the pink-eye-dilution gene (P) with hypopigmentation is seen in patients who have oculocutaneous albinism type 2 (OCA2) and prader-willi syndrome (PWS) or angelman syndrome (AS). However, it remains unknown whether duplication or amplification of the P gene causes hyperpigmentation. We previously reported a woman who had hyperpigmentation with a duplication of the proximal part of 15q, including the P gene. Here, we describe an additional patient with mosaicism of inv dup(15) and clinical manifestations of severe psychmoter retardation, epilepsy, and pigmentary dysplasia showing mottled and linear patterns of hyperpigmentation. His karyotype was 47,XY, idic(15)(pter-->q14::q14-->pter)[38]/46,XY[12] de novo. Chromosomal fluorescence in situ hybridization (FISH) showed six copies of the P gene. Therefore, his cutaneous mosaicism might be caused by the presence of both normal and hyperpigmented skin due to multicopies of the P gene.- - - - - - - - - - ranking = 1keywords = karyotype (Clic here for more details about this article) |
8/44. Primary immunodeficiency in combination with transverse upper limb defect and anal atresia in a 34-year-old patient with Jacobsen syndrome.We describe a 34-year-old male patient with Jacobsen syndrome associated with a broad spectrum of anomalies and an increased susceptibility to infections. Features commonly seen in Jacobsen syndrome were short stature, mental retardation, congenital heart disease, cryptorchidism, strabismus, distal hypospadia glandis, and mild thrombocytopenia. Chromosome analysis disclosed a mosaic 46,XY,del(11)(q24.1)/46,XY karyotype with a very low percentage of normal cells. In addition, transverse upper limb defect, imperforate anus, and hearing impairment were noted. Cellular anomalies include functional impairment and deficiency of T-helper cells, and a low serum immunoglobulin m (IgM)-level. The presence of a transverse limb defect and primary immunodeficiency has not been reported previously in Jacobsen syndrome.- - - - - - - - - - ranking = 1keywords = karyotype (Clic here for more details about this article) |
9/44. mosaicism for an ectopic NOR at 8pter and a complex rearrangement of chromosome 8 in a patient with severe psychomotor retardation.We describe a 3-year-old girl with severe delays in mental and motor skills, a history of generalized seizures, and subtle dysmorphic features. Conventional cytogenetics revealed a mosaic karyotype. A de novo ectopic NOR at the telomeric region of the short arm of one chromosome 8 (8ps) was found in 90% of lymphocyte and in 98% of fibroblast metaphases. A small NOR-bearing marker chromosome and a large derivative chromosome 8 without short arm satellites (der(8)) were present in the remaining cells. FISH with a probe specific for centromeres 14 and 22 labeled both the telomeric region of 8ps and the small marker centromere. Der(8) included an inverted duplication of 8p and a rearranged duplication of 8q but lacked a second centromere. A subtelomeric probe for 8p revealed a cryptic deletion in 8ps and der(8). Thus, the karyotype represents a combination of submicroscopic partial monosomy 8pter and mosaic trisomy 8.- - - - - - - - - - ranking = 2keywords = karyotype (Clic here for more details about this article) |
10/44. Subterminal deletion/duplication event in an affected male due to maternal x chromosome pericentric inversion.We report a 13-month-old male infant with an apparently normal karyotype, severe growth and developmental delay, ichthyosis, hypogonadism, limb shortness, hypoplasia of the corpus callosum and a round, flat face and thin upper lip as a consequence of a subtelomeric del/dup event of the x chromosome. The recombinant x chromosome (rec(X)), derived from crossing-over within the inversion, was identified in a family, in which the mother is a carrier of pericentric inversion of one x chromosome and pericentric inversion of the heterochromatic region of chromosome 9. The inv(X) chromosome was also analysed in her sister and daughter. The rec(X) had a duplication of the segment Xq27.3-->Xqter and deletion of the Xp22.31-->Xpter and was interpreted as Xqter-Xq27.3::Xp22.31-Xqter. The rec (X) was characterised by FISH using a number of BAC probes. There are only three published reports of chromosome rearrangements resulting in a similar subtelomeric duplication of Xq in males. The proband's phenotype corresponds to descriptions of contiguous gene syndromes due to deletion of the STS, SHOX, ARSE and KAL genes. Despite the loss of the ARSE gene there was no evidence of chondrodysplasia punctata. Additional conditions associated with duplication of the Xq28 segment, such as severe growth retardation and developmental delay, a peculiar head shape, atrophy of the cerebral hemispheres and hypoplasia of the cerebellum and corpus callosum, were observed. CONCLUSION:Fluorescent in situ hybridisation techniques using subtelomeric dna probes are essential tools for detection of such complex submicroscopic chromosomal rearrangements as the dup/del event of the x chromosome described in our patient.- - - - - - - - - - ranking = 1keywords = karyotype (Clic here for more details about this article) |
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