Prenatal findings and molecular cytogenetic analyses of partial trisomy 12q (12q24.32→qter) and partial monosomy 21q (21q22.2→qter)

2006 ◽  
Vol 26 (4) ◽  
pp. 313-320 ◽  
Author(s):  
Chih-Ping Chen ◽  
Schu-Rern Chern ◽  
Chyi-Chyang Lin ◽  
Tzu-Hao Wang ◽  
Yueh-Chun Li ◽  
...  
2005 ◽  
Vol 25 (2) ◽  
pp. 112-118 ◽  
Author(s):  
Chih-Ping Chen ◽  
Shuan-Pei Lin ◽  
Chyi-Chyang Lin ◽  
Yueh-Chun Li ◽  
Schu-Rern Chern ◽  
...  

2020 ◽  
Vol 77 (7) ◽  
pp. 754-757
Author(s):  
Ivana Joksic ◽  
Thomas Liehr ◽  
Mina Toljic ◽  
Natasa Karadzov-Orlic ◽  
Zagorka Milovanovic ◽  
...  

Introduction. Partial trisomy of chromosome 12 long arm is rare condition with significant clinical impact and is usually diagnosed postnatally. Case report. We present prenatal sonographic findings and molecular cytogenetic characterization of partial trisomy 12q and partial monosomy 2q in two consecutive pregnancies of a healthy non-consanguineous couple. A 35-year-old pregnant woman G3P1A1 was referred to genetic counseling due to sonographic anomalies detected in the fetus. First trimester ultrasound examination revealed hyperechogenic focus in the left cardiac ventricle, single umbilical artery, hyperechogenic bowel and unilateral clubfoot with knee joint ankylosis. Previous pregnancy of the couple was terminated at 26th gestation weeks due to multiple fetal anomalies: bilateral ventriculomegaly, corpus callosum hypoplasia, single umbilical artery and clubfoot. In G3P1A1, amniocentesis was performed and cytogenetic analyses revealed a derivative chromosome 2. Subsequent cytogenetic analyses of parental lymphocytes showed that paternal karyotype was normal, while maternal karyotype showed a der(2). Metaphase fluorescence in situ hybridization (FISH) studies demonstrated partial trisomy 12q24.2?12qter and partial monosomy 2q37.3?2qter in the fetus, resulting from an unbalanced segregation of a maternal balanced translocation t(2;12)(q37.3;q24.2). To date, this is the first such prenatally detected case. Literature search revealed three more cases of prenatally detected partial trisomy 12q and anomalies described were consistent with ones detected in present case. Our findings contribute to further clinical delineation of partial trisomy 12q. Conclusion. Prenatal detection of single umbilical artery, clubfoot, arthogryposis and ventriculomegaly should alert suspicion to chromosome 12q aberrations.


PEDIATRICS ◽  
1970 ◽  
Vol 46 (1) ◽  
pp. 74-83
Author(s):  
Howard Singer ◽  
Nona Suzann Scaife

A male infant with failure to thrive was found to have a previously unreported combination of chromosomal structural abnormalities. Evidence is presented which characterizes the abnormal chromosomes as a late-replicating G ring and a pericentric inversion in an early replicating B group chromosome. The mechanisms of pericentric inversion and ring formation are discussed, and possible genetic consequences are noted. The patient's phenotype differed significantly from that of previously reported subjects with G rings, G deletions, and structural abnormalities of the B group. This phenotypic difference could be attributed to the apparent fact that the proband's G ring was a late replicator (G1) and earlier cases were not, on to the seeming variability in ring size which suggested partial trisomy/partial monosomy, or perhaps to the probability that the abnormal B chromosome was pericentrically inverted rather than deleted. The question of the etiologic significance of broken parental chromosomes must be raised, although more study is needed in the area of chromosome breakage, its relationship to abnormal progeny, and the possible role of environmental agents, e.g., drugs and irradiation.


Sign in / Sign up

Export Citation Format

Share Document