1/10. 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) |
2/10. Acampomelic campomelic syndrome.Campomelic syndrome (or campomelic dysostosis, CD; MIM *114290) is an autosomal dominant skeletal malformation syndrome characterized by shortness and bowing of long bones, especially of the lower limbs. Additional radiological and clinical findings are 11 pairs of ribs and a bell-shaped thorax, hypoplastic scapulae, narrow iliac wings, non-mineralized thoracic pedicles, clubbed feet, Robin sequence, typical facial anomalies and tracheomalacia. The disorder is frequently lethal due to respiratory distress. sex reversal occurs in most patients with an XY karyotype. CD is caused by heterozygous mutations in the SOX9 gene, an SRY-related gene at 17q24.3-q25.1 with pleiotropic effects on the skeletal and genital systems. In addition, cases with chromosomal rearrangements involving 17q have been described that are most likely caused by disturbing one or more cis-regulatory elements from an extended control region. Campomelia (bowed limbs) is seen in most but not all patients, defining a so-called acampomelic campomelic dysostosis (ACD). Half of the CD cases with 17q rearrangements have no or mild campomelia. Furthermore, campomelia is absent or only mildly present in a small subgroup of cases with a normal karyotype. We present a chromosomally normal boy with ACD and his clinical follow-up up to the age of 2 years, in whom a heterozygous SOX9 missense mutation (H165Y) was identified. A SOX9 missense mutation was published in two other patients with ACD. Although up to now a general genotype-phenotype correlation could not be established for CD, a correlation emerges for the ACD variant that needs further confirmation.- - - - - - - - - - ranking = 2keywords = karyotype (Clic here for more details about this article) |
3/10. Mosaic trisomy 15 in a short girl with hemihypotrophy and mental retardation.We describe a girl with short stature, mild mental retardation, hemihypotrophy, atrial septal defect I, bilateral branchial cleft fistulas and abnormal skin pigmentation. growth hormone deficiency and other frequent causes of short stature were excluded. blood karyotype was investigated twice. In one sample an additional marker chromosome was found in one of 53 analysed metaphases, which could not be further characterized, whereas a second investigation showed a normal female karyotype. Cytogenetic studies in skin fibroblasts revealed a mosaic trisomy 15. Although mosaic trisomy 15 is a rare finding the diagnosis must be considered in the presence of pigmentary changes, body asymmetry, short stature and other minor dysmorphic signs even if blood karyotype is normal.- - - - - - - - - - ranking = 3keywords = karyotype (Clic here for more details about this article) |
4/10. Position effects due to chromosome breakpoints that map approximately 900 Kb upstream and approximately 1.3 Mb downstream of SOX9 in two patients with campomelic dysplasia.campomelic dysplasia (CD) is a semilethal skeletal malformation syndrome with or without XY sex reversal. In addition to the multiple mutations found within the sex-determining region Y-related high-mobility group box gene (SOX9) on 17q24.3, several chromosome anomalies (translocations, inversions, and deletions) with breakpoints scattered over 1 Mb upstream of SOX9 have been described. Here, we present a balanced translocation, t(4;17)(q28.3;q24.3), segregating in a family with a mild acampomelic CD with Robin sequence. Both chromosome breakpoints have been identified by fluorescence in situ hybridization and have been sequenced using a somatic cell hybrid. The 17q24.3 breakpoint maps approximately 900 kb upstream of SOX9, which is within the same bacterial artificial chromosome clone as the breakpoints of two other reported patients with mild CD. We also report a prenatal identification of acampomelic CD with male-to-female sex reversal in a fetus with a de novo balanced complex karyotype, 46,XY,t(4;7;8;17)(4qter-->4p15.1::17q25.1-->17qter;7qter-->7p15.3::4p15.1-->4pter ;8pter-->8q12.1::7p15.3-->7pter;17pter-->17q25.1::8q12.1-->8qter). Surprisingly, the 17q breakpoint maps approximately 1.3 Mb downstream of SOX9, making this the longest-range position effect found in the field of human genetics and the first report of a patient with CD with the chromosome breakpoint mapping 3' of SOX9. By using the Regulatory Potential score in conjunction with analysis of the rearrangement breakpoints, we identified a candidate upstream cis-regulatory element, SOX9cre1. We provide evidence that this 1.1-kb evolutionarily conserved element and the downstream breakpoint region colocalize with SOX9 in the interphase nucleus, despite being located 1.1 Mb upstream and 1.3 Mb downstream of it, respectively. The potential molecular mechanism responsible for the position effect is discussed.- - - - - - - - - - ranking = 1keywords = karyotype (Clic here for more details about this article) |
5/10. Twin pregnancy with Roberts syndrome in one fetus and trisomy 18 in the other.We report a case of a 26-year-old multigravida pregnant woman with a history of 3 stillbirths with hydrops fetalis who presented with 17 weeks menstrual age. Sonographic examination revealed twin gestation. Twin 1 showed subcutaneous edema, pleural effusion, and mesomelic limb shortening, suggestive of lethal skeletal dysplasia (Roberts syndrome). Twin 2 corresponded to 17 weeks menstrual age with no major malformations. karyotyping of the fetuses showed normal karyotype in twin 1 and trisomy 18 in twin 2. Fetal autopsy confirmed the sonographic findings. The occurrence of trisomy 18 in the fetus may be due to chance, but it raises the possibility that the heterozygotes of Roberts syndrome may be at higher risk of nondisjunction and aneuploidy in the fetus. Furthermore, this case illustrates that karyotyping of both fetuses is warranted when 1 of the twins is found to have major malformations.- - - - - - - - - - ranking = 1keywords = karyotype (Clic here for more details about this article) |
6/10. Partial trisomy 17q and a generalised bone dysplasia in a 12 week fetus.A fetus, which was spontaneously aborted at 12 weeks' gestation, was found to have a generalised bone dysplasia and an unbalanced karyotype with trisomy for 17q23.1 qter due to a maternal translocation: 46,XX,t(5;17)(p15.3;q23.1)mat.- - - - - - - - - - ranking = 1keywords = karyotype (Clic here for more details about this article) |
7/10. New chromosomal dysmorphic syndromes. 3. Partial trisomy 3q.Chromosome analysis in a newborn, the daughter of diabetic parents, who showed multiple dysmorphic signs and malformations revealed direct duplication of a long arm segment of chromosome 3(3q2100 leads to 3q2700). Both parents have normal karyotypes. Compilation of the phenotype stigmata with those of 7 other patients and 1 fetus with partial trisomy 3q confirmed that clinical recognition of this syndrome is possible. It is characterized by hypertrichosis, typical craniofacial dysmorphia, frequent organ malformations and skeletal anomalies, as well as a peculiar dermatoglyphic pattern. It is a severe genetic disturbance, leading to death in the first months of life in many cases and only symptomatic care is advised.- - - - - - - - - - ranking = 1keywords = karyotype (Clic here for more details about this article) |
8/10. Ring chromosome 15: phenotype, Ag-NOR analysis, secondary aneuploidy, and associated chromosome instability.cytogenetic analysis of a 15 month old girl evaluated for severe developmental delay and acral skeletal hypoplasia revealed a predominant 46,XX,r(15) karyotype. prophase banding analysis showed minimal deletion of the ring chromosome (breakpoints p12 and q26), while silver staining showed it to have an active nucleolus organizing region, multiple abnormal secondary configurations, and decreased satellite association. Although there was no spontaneous instability in the rest of the karyotype, gentian violet-induced chromosome breakage was significantly increased. The rate of spontaneous sister chromatid exchange was not elevated. Cellular mosaicism for chromosome 15 aneuploidy most likely accounts for the patient's phenotypic abnormalities.- - - - - - - - - - ranking = 2keywords = karyotype (Clic here for more details about this article) |
9/10. 3-Year-old phenotypic female with campomelic dysplasia and bilateral gonadoblastoma.The authors report the case of bilateral gonadoblastomas in a phenotypic female, with a 46,XY karyotype, with campomelic dysplasia. Although campomelic dysplasia with gonadal dysgenesis should be expected to contribute to an increased risk of gonadoblastoma, this is the first documented case report of campomelic dysplasia and gonadoblastoma. Phenotypic females with campomelic dysplasia should be karyotyped once the skeletal dysplasia is recognized. phenotypic females with campomelic dysplasia should undergo gonadectomy if their karyotype includes a y chromosome or fragment.- - - - - - - - - - ranking = 3keywords = karyotype (Clic here for more details about this article) |
10/10. Kyphomelic dysplasia in two sib fetuses.We present the in utero appearances and postmortem radiographic findings of two sib fetuses, a male and a female, with features suggestive of kyphomelic dysplasia. The fetuses had severe bowing of the long bones, short, flared ribs, platyspondyly, metaphyseal flaring, skin dimpling, with normal external genitalia and karyotypes and a normal pregnancy. They were born to a mother with features of brachydactyly type E. Prenatal ultrasonography of each case showed a normal amount of amniotic fluid, a normal brain, a normal biparietal diameter, symmetrical bowing and shortening of the long bones, and a narrow thorax. Our cases provide support for a familial mode of inheritance for both sexes in kyphomelic dysplasia. Prenatal ultrasound examination can be offered in subsequent pregnancies.- - - - - - - - - - ranking = 1keywords = karyotype (Clic here for more details about this article) |
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