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.

Prenatal diagnosis of sub-microscopic partial trisomy 10q using chromosomal microarray analysis in a phenotypically abnormal fetus with normal karyotype

Partial trisomy of the 10q region was originally reported in 1979 [1]. For 25 years, the diagnosis was made microscopically based on large, visible insertions in the region identified by karyotype analysis. Previous case reports have included both unbalanced translocations and large duplications/insertions in the 10q region [2]. Probands with partial trisomy 10q syndrome often have an abnormal phenotype that may include developmental delay [3-5], craniofacial abnormalities [3, 5], talipes (clubfoot) [2], microcephaly [2-4], or congenital heart disease [2-6]. Prenatal diagnoses by karyotype have been made following ultrasound diagnosis of sacrococcygeal teratoma [7], renal pyelectasis [3, 8-10], and other fetal abnormalities [4]. In this case, we report the first prenatal diagnosis of partial trisomy 10q (10q22.3-10q23.2) with a normal karyotype and an abnormal chromosomal microarray analysis (CMA). This is the smallest copy number variant (CNV) (7.5 Mb) in the 10q22.3-10q23.2 regions yet reported.

Distal 10q trisomy with copy number gain in chromosome region 10q23.1-10q25.1: the Wnt signaling pathway is the most pertinent to the gene content in the region of copy number gain: a case report

Background

Complete or partial trisomy 10q involves a duplication of 10q, or the long arm of chromosome 10. Distal 10q trisomy is a well-recognized and defined but rare genetic syndrome in which duplication of distal segments of 10q results in a pattern of malformations. Although abnormal chromosome phenotypes are commonly detected by visualization of chromosomes by traditional cytogenetic techniques, this approach is marginal in both diagnostic sensitivity and potential for biological interpretation, thus making implementation of advanced techniques and analysis methods an important consideration in a health service.

Case presentation

The present study describes the case of a Taiwanese boy from healthy parents with mental, growth, and psychomotor retardations. Additional clinical features included facial dysmorphism, microcephaly, brain atrophy, camptodactyly, and—as the first reported case—bilateral renal atrophy with chronic kidney disease stage 2 and the presence of a renal cyst in one kidney. A novel 21.8 Mb copy number variation region in chromosome region 10q23.1–10q25.1 was verified by array-comparative genomic hybridization in combination with quantitative real-time polymerase chain reaction. Subsequently, 200 protein-coding genes were identified in this copy number variation region and analyzed for their biological meaning using the database for annotation, visualization and integrated discovery.

Conclusion

According to the result of gene functional enrichment analysis using database for annotation, visualization and integrated discovery, the Wnt signaling pathway is the most pertinent to the gene content in the copy number variation region. A change in the expression levels of some Wnt signaling pathway components and of NFKB2 and PTEN genes due to a gain in their gene copy number may be associated with the patient’s clinical outcomes including brain atrophy, bilateral renal atrophy with chronic kidney disease stage 2, a renal cyst in one kidney, and growth retardation.

Electronic supplementary material

The online version of this article (doi:10.1186/s13104-015-1213-x) contains supplementary material, which is available to authorized users.