Prenatal diagnosis of a fetus with distal 10q trisomy

Prenatal diagnosis of partial monosomy 2q (2q37.3→qter) and partial trisomy 10q (10q24.31→qter) of paternal origin associated with increased nuchal translucency and abnormal maternal serum screening results

OBJECTIVE

We present prenatal diagnosis of terminal 2q deletion and distal 10q duplication of paternal origin in a fetus associated with increased nuchal translucency and abnormal maternal serum screening results.

CASE REPORT

A 26-year-old woman who had experienced spontaneous abortion twice underwent amniocentesis at 16 weeks of gestation because of an increased nuchal translucency thickness of 3.5 mm at 12 weeks of gestation and abnormal maternal serum screening results of 2.573 multiples of the median (MoM) of free β-human chorionic gonadotrophin (β-hCG) and 1.536 MoM of pregnancy-associated plasma protein-A (PAPP-A) resulting in a trisomy 21 risk of 1:64. Amniocentesis revealed a derivative chromosome 2. Simultaneous array comparative genomic hybridization (aCGH) analysis on the DNA extracted from uncultured amniocytes revealed arr [hg19] 2q37.3 (238,294,223-242,782,258) × 1, 10q24.31q26.3 (102,018,246-135,426,386) × 3. Cytogenetic analysis of parental bloods revealed a karyotype of 46,XX in the mother and a karyotype of 46,XY,t(2;10)(q37.3;q24.3) in the father. The fetal karyotype was 46,XX,der(2)t(2;10)(q37.3;q24.3)pat. The pregnancy was terminated at 20 weeks of gestation, and a malformed fetus was delivered with facial dysmorphism. Postnatal analysis of the cord blood confirmed the results of prenatal diagnosis. The fetus had a 4.693-Mb deletion of 2q37.3 encompassing the genes of HDAC4, KIF1A, PASK, HDLBP, FARP2 and D2HGDH, and a 33.34-Mb duplication of 10q24.31-q26.3 encompassing the gene of NFκB2.

CONCLUSION

First-trimester ultrasound and maternal serum biochemistry screening may help to identify an unexpected unbalanced familial translocation at prenatal diagnosis.

Neurodevelopmental Impairment As the Main Phenotypic Hallmark Associated with the Translocation t(7;10)(7p22.3;q26.11)

Reported here is a novel patient carrying an unbalanced t (10q26.11-q26.3; 7p22.3) and presenting with a severe intellectual disability with autistic features, abnormalities of muscle tone, and a drug-responsive epilepsy. The prominence of neurological and neurodevelopmental abnormalities in the clinical phenotype highlights a possible pathogenic role for different genes in the involved regions. Hypothetical mechanisms may include a possible gene dosage effect for DOCK1 and/or haploinsufficiency of PRKAR1B SUN1, ADAP1 , and GPER1 .

Early renal insufficiency in a neonate with de novo partial trisomy of chromosome 10q

Partial trisomy of the long arm of chromosome 10 is a well-defined but rare syndrome. Clinical features of this chromosomopathy are a distinctive dysmorphic appearance, developmental delay, growth retardation, and in some cases, abnormalities of the extremities and renal, cardiac and ocular anomalies. This report describes a neonate with symmetric growth retardation and multiple dysmorphic features, in whom chromosomal analysis revealed a partial trisomy of chromosome 10q with a monosomy of the 13q34 region. The phenotype shares many common features with previously published cases. In addition to the typical features, our case also shows renal hypoplasia with early renal insufficiency and some genital anomalies.

Distal trisomy 10q and limb defects

Analysis of the literature showed that hypoplasia (or aplasia) of tibiae was found at least in six persons with trisomy 10q25.2-qter. Therefore, these defects should be considered as a characteristic manifestation of the distal trisomy 10q. In most of these patients, tibial abnormalities were associated with other defects of the lower extremities (hypoplastic femora, ectrodactyly, preaxial polydactyly). Upper limbs were affected in one patient (as well as in her sib without tibial defects). Most likely, segment 10q25.2-qter contains a gene which (when triplicated) leads to maldevelopment of the limbs, and tibial malformations are only one manifestation of this field defect.

Distal trisomy of 10q. Report of a new case of duplication 10q25.2-25.3-->qter defined by FISH

In the present work, we report on a 2.5-year-old male patient with typical clinical features of partial trisomy of the distal third of chromosome 10 long arm. The karyotype was: 46,XY, dir dup(10)(q25.2-25.3-->qter). The identification of the duplicated segment was carried out by the fluorescence in situ hybridization technique using region-specific probes. The proband's phenotype is compared with previously reported cases.

Trisomy 10: ultrasound features and natural history after first trimester diagnosis

We report on the ultrasound features and natural history of trisomy 10. At 12 weeks' gestation in a routine scan examination, the fetus presented with increased nuchal translucency thickness, mild skin oedema, bilateral pleural effusion, marked micrognathia, cardiomegaly, unilateral talipes and reversed A-wave in the ductus venosus blood flow. Karyotyping on chorionic villus sampling (CVS) led to the diagnosis of trisomy 10, which was confirmed by fetal blood sampling at 22 weeks' gestation. As the parents opted to continue with the pregnancy, the natural history and following ultrasound features are described. This is the third case of trisomy 10 in the literature reporting on the physical features. The most frequent ultrasound findings presented in trisomy 10 are increased nuchal translucency, micrognathia, renal agenesis, facial cleft, limbabnormalities, cardiac defects and early severe growth retardation.

Molecular cytogenetics and phenotype characterization of a de novo pure partial trisomy 10(q24.33-qter)

The molecular-cytogenetic characterization of a de novo pure partial trisomy 10(q24.33-qter) is described. This report provides information about the postnatal phenotype. The clinical findings observed in this case support the conclusion that the more severe disease related genes are located between 10q24.1 and q24.33.