Trisomy 21 in mother and daughter

A 28-year-old woman with trisomy 21 had a daughter with trisomy 21. This case brings the total to 23 mothers recorded as having trisomy 21. Their offspring consist of 14 normals and 10 trisomics, 21 born at term, plus 3 abortions. The proportions of normal and trisomic offspring are about equal.     

Trisomy 21 in transient myeloproliferative disorder

Transient leukemia in phenotypically normal children is rare. A newborn child in whom fever and tachypnea developed at age 2 days had a white blood cell count of 20.1 x 10(9)/L and many abnormal blast cells. Chromosome analysis of spontaneously dividing cells from the blood showed these to have trisomy 21, and 80% of cells in the marrow were also trisomic. No trisomic cells were present in skin fibroblast cultures. At age 6 months, at which time the blood film appeared normal, trisomic cells were no longer present.     

Trisomy 18 and 21 in two siblings

While a child with trisomy 21 is a generally accepted indication for amniocentesis in succeeding pregnancies, the need for this prenatal test following a child with trisomy 18 is less certain. Although the likelihood of two successive pregnancies resulting in trisomies (18 and 21) appears to be small, it may be more common than is generally realized due to the high mortality of trisomy 18 prior to diagnostic studies.     

Trisomy 18 at age 21 years

Here we report on a woman with non-mosaic trisomy 18, who is now 21 years old. She has the characteristic face of older trisomy 18 survivors, marked kyphoscoliosis, spastic quadriplegia with contractures, and profound mental retardation. She has pyorrhea with loss of three canine teeth. At 20.5 years, she had her first menstrual cycle with development of secondary sexual characteristics.     

Trisomy 18 at age 21 years

Here we report on a woman with non-mosaic trisomy 18, who is now 21 years old. She has the characteristic face of older trisomy 18 survivors, marked kyphoscoliosis, spastic quadriplegia with contractures, and profound mental retardation. She has pyorrhea with loss of three canine teeth. At 20.5 years, she had her first menstrual cycle with development of secondary sexual characteristics.     

Mouse Models of Cognitive Disorders in Trisomy 21: A Review

Trisomy 21 (TRS21) is the most frequent genetic cause of mental retardation. Although the presence of an extra copy of HSA21 is known to be at the origin of the syndrome, we do not know which 225 HSA21 genes have an effect on cognitive processes. Mouse models of TRS21 have been developed using syntenies between HSA21 and MMU16, MMU10 and MMU17. Available mouse models carry extra fragments of MMU16 or of HSA21 that cover all of HSA21 (chimeric HSA21) or MMU16 (Ts16); some carry large parts of MMU16 (Ts65Dn, Ts1Cje, Ms1Cje), while others have reduced contiguous fragments covering the D21S17-ETS2 region or single transfected genes. This offers a nest design strategy for deciphering cognitive (learning, memory and exploration) and associated brain abnormalities involving each of these chromosomal regions. This review confirms the crucial but not exclusive contribution of the D21S17-ETS2 region encompassing 16 genes to cognitive disorders.     

Gene-Dosage Effect on Chromosome 21 Transcriptome in Trisomy 21: Implication in Down Syndrome Cognitive Disorders

In the era of human functional genomics, the chromosome 21 has represented a prototype for pioneering global biotechnologies. Its relatively low gene content enabled studying Down syndrome at the chromosomal scale, for which the last years have seen intense research activity aiming at genotype-phenotype correlations. The global gene-dose dependent upregulation of gene expression seen in the context of trisomy and preliminary functional annotation of chromosome 21 genes points towards candidate genes and molecular pathways potentially associated with the cognitive defects observed in Down syndrome.     

The familial prevalence in second-degree relatives of patients with anxiety neurosis (panic disorder)

A family history study of second-degree relatives of 19 patients with anxiety neurosis (panic disorder) and 19 controls showed a morbidity risk of 9.5% among the former compared with 1.4% among the latter. These risks were approximately half those found among first-degree relatives. Female relatives were at higher risk for anxiety neurosis. The risk for other psychiatric illnesses did not differ between the relatives of anxiety neurosis and controls.     

Trisomy 4p in four relatives: variability and lack of distinctive features in phenotypic expression

We report two brothers and two second cousins with 4p trisomy secondary to a familial translocation t(4;7) (p12;q36). A comparison of their physical features demonstrates the variability of clinical manifestations associated with this chromosome abnormality. While previous authors have emphasized the distinctiveness of the 4p trisomy syndrome, the variability seen in the affected relatives in this family suggests that trisomy 4p is one of the less distinctive chromosomal syndromes. Further comparison of our patients with the previously reported cases of 4p trisomy and with two cases whose chromosomal breakpoints were similar confirms this variability. Studies of phenotype/karyotype correlations in affected relatives provides the best opportunity to determine the phenotypic consequences of a specific (that is, identical) translocation. Studies of unrelated persons are complicated by the effects of different breakpoints and of possible partial deletions.     

Trisomy 21 and isodicentric chromosome 21 in Kostmann syndrome following treatment with G-CSF

A child with Kostmann syndrome, or severe congenital neutropenia, developed myelodysplastic syndrome after 6 years of treatment with rhG-CSF. The bone marrow karyotype showed acquired trisomy 21, and in some cells pentasomy 21 due to two isodicentric chromosomes 21. This is the second report of a patient with Kostmann syndrome and acquired trisomy 21.     

Trisomy 21 mosaicism in a woman with two children with trisomy 21 Down''s syndrome

Trisomy 21 mosaicism was identified by fluorescent quinacrine banding in a phenotypically normal mother, who gave birth to two children with trisomy 21 Down's syndrome.     

中国21三体综合征流行病学研究

２１三体综合征的现况研究旨在通过流行病学研究方法，了解中国２１三体综合征的现患率及其分布特征。采用分层、不等比例、多阶段、随机整群的抽样方法，现场调查采用智力诊断和先天畸形的双重筛查及Ｇ显带核型分析方法。发现我国２１三体综合征的总现患率为０．４７‰，城市为０．２６‰，农村为０．５６‰。农村明显高于城市，男性高于女性，全部表现智力低下，多为中、重度     

Decreased Cord Blood IgM and IgA in Trisomy 21*

ABSTRACT: Disagreement as to whether Ig levels are high, low, or normal at different ages in different groups of trisomic children has interfered with defining the associated immunodeficiency state. Fetal Ig production was assessed by measuring cord blood IgM and IgA of five trisomy 21, 97 normal, and 37 control newborns with other birth defects. Trisomic infants showed significantly lower values. Cord blood IgG values showed no differences between groups when corrected for fetal birth weight. The data indicate that children with trisomy 21 have an impaired humoral immune response in utero.     

Trisomy 21 and other chromosomal abnormalities in acute promyelocytic leukemia

We describe a case of acute promyelocytic leukemia (APL) with t(15;17)(q22;q12) and trisomy 21 as an additional change in a patient who died at relapse after achieving complete remission (CR) for the duration of 20 months. A survey of 42 cases of APL with cytogenetic study performed at our institution over the past 10 years showed 12 cases (28.6%) having chromosomal changes in addition to t(15;17). Trisomy 8 and trisomy 21 as additional changes were noted in 4 and 2 cases, respectively, with one patient showing both trisomies simultaneously. Two cases showed t(15;17) in hyperdiploid clones. Among the 10 patients with follow-up data, all eventually relapsed and none achieved continuous complete remission 1. Survival analysis performed in APL patients with adequate follow-up data showed no significant difference in overall and disease free survival between those with and without additional cytogenetic changes. After excluding cases with one induction death, the overall survival was significantly in favor of the group without additional cytogenetic abnormalities (P = 0.022). Late relapses may therefore be significantly more common in APL patients with additional cytogenetic abnormalities, and may not be reflected by analysis focused at three-year survival only. As APL is now considered a curable disease, any confirmed long-term survival impact of additional cytogenetic changes is expected to have important management implications.