Article

Diagnostic utility of array-based comparative genomic hybridization (aCGH) in a prenatal setting.

The Raphael Recanati Genetic Institute, Rabin Medical Center, Beilinson Hospital, Petah Tikva, Israel.
Prenatal Diagnosis (Impact Factor: 2.68). 10/2010; 30(12-13):1131-7. DOI: 10.1002/pd.2626
Source: PubMed

ABSTRACT Array-based comparative genomic hybridization (aCGH) is a new technique for detecting submicroscopic deletions and duplications. There is limited information regarding its use in the prenatal setting. Here, we present our experience of 269 prenatal aCGHs between 2006 and 2009.
The indications for testing were fetal anomalies on ultrasound (U/S), advanced maternal age (AMA), family history of a disorder of unknown etiology, parental concern, abnormal routine karyotype and abnormal serum biochemical screening for common fetal aneuploidies.
Of 15 cases with a known abnormal karyotype, 11 had a normal aCGH. This enabled us to reassure the families and the pregnancies were continued. The remaining four showed an abnormal aCGH, confirming the chromosomes were unbalanced, and were terminated. Of 254 cases with a normal karyotype, 3 had an abnormal aCGH and were terminated. Overall, new clinically relevant results were detected by aCGH in 18 cases, providing additional information for prenatal genetic counseling and risk assessment.
Our results suggest that prenatal aCGH should be offered particularly in cases with abnormal U/S. We found the rate of detecting an abnormality by aCGH in low-risk pregnancies was 1:84, but larger studies will be needed to expand our knowledge and validate our conclusions.

0 Bookmarks
 · 
94 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: When congenital anomalies are diagnosed on prenatal ultrasound, the current standard of care is to perform G-banded karyotyping on cultured amniotic cells. Chromosomal microarray (CMA) can detect smaller genomic deletions and duplications than traditional karyotype analysis. CMA is the first-tier test in the postnatal evaluation of children with multiple congenital anomalies. Recent studies have demonstrated the utility of CMA in the prenatal setting and have advocated for widespread implementation of this technology as the preferred test in prenatal diagnosis. However, CMA remains significantly more expensive than karyotype. In this study, we performed an economic analysis of cytogenetic technologies in the prenatal diagnosis of sonographically detected fetal anomalies comparing four strategies: (i) karyotype alone, (ii) CMA alone, (iii) karyotype and CMA, and (iv) karyotype followed by CMA if the karyotype was normal. In a theoretical cohort of 1,000 patients, CMA alone and karyotype followed by CMA if the karyotype was normal identified a similar number of chromosomal abnormalities. In this model, CMA alone was the most cost-effective strategy, although karyotype alone and CMA following a normal karyotype are both acceptable alternatives. This study supports the clinical utility of CMA in the prenatal diagnosis of sonographically detected fetal anomalies. © 2014 Wiley Periodicals, Inc.
    American Journal of Medical Genetics Part A 03/2014; · 2.30 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The main aim of this study was to determine the feasibility of using high-resolution microarray to assist with prenatal diagnosis of ultrasound-detected fetal abnormality and to describe the frequency of abnormal results in different categories of fetal anomalies. Prospective cross-sectional study was conducted on women diagnosed with a fetal anomaly (ies) between February 2009 and December 2011 who were offered testing by microarray analysis (Affymetrix 2.7M SNP) and fluorescent in situ hybridisation (FISH) instead of standard karyotyping. Fetal anomalies were categorised according to organ system involvement. One hundred and eighteen women consented to testing with microarray. Eleven of one hundred eighteen (9.3%) cases had aneuploidy detected by FISH. Of the remaining 107, 23 (21.5%) had an abnormality detected on microarray, only three of which would have been detected using the combination of six-probe FISH and banded karyotype. The maximum expected yield for six-probe FISH and karyotype was thus 14/118 (11.8%), compared to 34/118 (28.8%), P < 0.0001. Of the 23 abnormalities detected with microarray, 10 (43%) were pathogenic, six (26%) were long continuous stretches of homozygosity and seven (30%) were of uncertain significance. The maximum yield was in cases with cardiovascular (100%); multiple (40%); central nervous system (CNS) (25%) and skeletal (9%) abnormalities. This study has confirmed the feasibility of translation of microarray into clinical practice. 11.8% (14/118) of the cases would have a genetic basis of an abnormality with a FISH and banded karyotype. This figure is approximately tripled to 28.8% (34/118) if we offer FISH and microarray. High yield for imbalances are multiple, cardiovascular, CNS and skeletal abnormalities.
    Australian and New Zealand Journal of Obstetrics and Gynaecology 02/2014; 54(1):46-52. · 1.30 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Array-based comparative genomic hybridization possesses a number of significant advantages over conventional cytogenetic and other molecular cytogenetic techniques, providing a sensitive and comprehensive detection platform for unexpected imbalances in the genome wide. The newborn proband, demonstrated with craniofacial dysmorphism and multiple malformations, was born to a family with spontaneous abortions. This pregnancy was uneventful, except the prenatal ultrasound examination showed an increased nuchal translucency at 12+ weeks of gestation. Cytogenetics revealed an apparently normal karyotype, and the couple decided to continue the pregnancy. Array-based CGH analysis was applied to the affected infant, identified a combination of 18p deletion and 7q duplication. Further study indicates that the unbalanced translocation was inherited from a balanced translocation carrier parent. In review of the case, several overlooked points leading to the missed diagnosis should be discussed and certain quality control strategies should be adopted to avoid similar problems in the future. Array-based CGH and karyotyping techniques are complemented by diverse detection spectrum and resolutions, and a combination of these methods could help providing optimal genetic diagnosis. Given that the array-CGH analysis will not introduce additional risk to patients, it is reasonable to recommend those already undergoing invasive testing should take array-based CGH as an adjunct to conventional cytogenetic tests and other molecular cytogenetic analysis.
    Molecular Cytogenetics 04/2014; 7(1):26. · 2.36 Impact Factor