Talk:Comparative Genomic Hybridization
Preimplantation genetic screening for all 24 chromosomes by microarray comparative genomic hybridization significantly increases implantation rates and clinical pregnancy rates in patients undergoing in vitro fertilization with poor prognosis
J Hum Reprod Sci. 2016 Apr-Jun;9(2):94-100. doi: 10.4103/0974-1208.183512.
Majumdar G1, Majumdar A1, Lall M2, Verma IC3, Upadhyaya KC4.
CONTEXT: A majority of human embryos produced in vitro are aneuploid, especially in couples undergoing in vitro fertilization (IVF) with poor prognosis. Preimplantation genetic screening (PGS) for all 24 chromosomes has the potential to select the most euploid embryos for transfer in such cases. AIM: To study the efficacy of PGS for all 24 chromosomes by microarray comparative genomic hybridization (array CGH) in Indian couples undergoing IVF cycles with poor prognosis. SETTINGS AND DESIGN: A retrospective, case-control study was undertaken in an institution-based tertiary care IVF center to compare the clinical outcomes of twenty patients, who underwent 21 PGS cycles with poor prognosis, with 128 non-PGS patients in the control group, with the same inclusion criterion as for the PGS group. MATERIALS AND METHODS: Single cells were obtained by laser-assisted embryo biopsy from day 3 embryos and subsequently analyzed by array CGH for all 24 chromosomes. Once the array CGH results were available on the morning of day 5, only chromosomally normal embryos that had progressed to blastocyst stage were transferred. RESULTS: The implantation rate and clinical pregnancy rate (PR) per transfer were found to be significantly higher in the PGS group than in the control group (63.2% vs. 26.2%, P = 0.001 and 73.3% vs. 36.7%, P = 0.006, respectively), while the multiple PRs sharply declined from 31.9% to 9.1% in the PGS group. CONCLUSIONS: In this pilot study, we have shown that PGS by array CGH can improve the clinical outcome in patients undergoing IVF with poor prognosis. KEYWORDS: Array comparative genomic hybridization; clinical outcomes; embryo selection; in vitro fertilization; preimplantation genetic screening
A French Approach to Test Fetuses with Ultrasound Abnormalities Using a Customized Microarray as First-Tier Genetic Test
Cytogenet Genome Res. 2015;147(2-3):103-10. doi: 10.1159/000442904. Epub 2016 Jan 7.
Malan V1, Lapierre JM, Egloff M, Goidin D, Beaujard MP, Maurin ML, Attié-Bitach T, Bessières B, Bernard JP, Roth P, Stirnemann J, Salomon L, Romana S, Vekemans M, Ville Y, Turleau C. Author information 1Service d'Histologie-Embryologie-Cytogx00E9;nx00E9;tique, Hx00F4;pital Necker-Enfants Malades, AP-HP, Paris, France. Abstract Cytogenetic microarray analysis is now the first-tier genetic test used in a postnatal clinical setting to explore genomic imbalances in individuals with developmental disability and/or birth defects. However, in a prenatal setting, this technique is not widely implemented, largely because the clinical impact of some copy number variants (CNVs) remains difficult to assess. This limitation is especially true in France where termination of pregnancy for medical reasons may be performed at any stage of gestation. During a period of 15 months, we investigated 382 fetuses presenting with ultrasound anomalies, using a customized microarray designed to avoid the detection of CNVs raising challenges for genetic counseling. After excluding common aneuploidies, 20/374 (5.3%) fetuses had a pathogenic CNV, among which 12/374 (3.2%) could have been detected by karyotyping, whereas 8/374 (2.1%) were cryptic. Within these 374 cases, 300 were ongoing pregnancies at the time of array comparative genomic hybridization (aCGH) testing. For these pregnancies, we detected 18/300 (6%) pathogenic CNVs, among which 6/300 (2%) were cryptic. Using this approach, only 2/300 (0.6%) of the detected CNVs raised difficulties for genetic counseling. This study confirms the added value of this strategy in a prenatal clinical setting to minimize ethical issues for genetic counseling while enhancing the detection of genomic imbalances. © 2016 S. Karger AG, Basel.
Non-invasive tool for foetal sex determination in early gestational age
Haemophilia. 2011 Apr 15. doi: 10.1111/j.1365-2516.2011.02537.x. [Epub ahead of print]
Mortarino M, Garagiola I, Lotta LA, Siboni SM, Semprini AE, Peyvandi F.
U.O.S. Dipartimentale per la Diagnosi e la Terapia delle Coagulopatie, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, Fondazione IRCCS Ca' Granda-Ospedale Maggiore Policlinico, University of Milan and Luigi Villa Foundation, Milan, Italy Clinica Ostetrica e Ginecologica, Ospedale Luigi Sacco, University of Milan, Milan, Italy.
Abstract Summary. Free foetal DNA in maternal blood during early pregnancy is an ideal source of foetal genetic material for non-invasive prenatal diagnosis. The aim of this study was to evaluate the use of free foetal DNA analysis at early gestational age as pretest for the detection of specific Y-chromosome sequences in maternal plasma of women who are carriers of X-linked disorders, such as haemophilia. Real-time quantitative PCR analysis of maternal plasma was performed for the detection of the SRY or DYS14 sequence. A group of 208 pregnant women, at different gestational periods from 4 to 12 weeks, were tested to identify the optimal period to obtain an adequate amount of foetal DNA for prenatal diagnosis. Foetal gender was determined in 181 pregnant women sampled throughout pregnancy. Pregnancy outcome and foetal gender were confirmed using karyotyping, ultrasonography or after birth. The sensitivity, which was low between 4th and 7th week (mean 73%), increased significantly after 7+1th weeks of gestation (mean 94%). The latter sensitivity after 7+1th week of gestation is associated to a high specificity (100%), with an overall accuracy of 96% for foetal gender determination. This analysis demonstrates that foetal gender determination in maternal plasma is reliable after the 9th week of gestation and it can be used, in association with ultrasonography, for screening to determine the need for chorionic villus sampling for prenatal diagnosis of X-linked disorders, such as haemophilia.
© 2011 Blackwell Publishing Ltd.
Rapid aneuploidy diagnosis by multiplex ligation-dependent probe amplification and array comparative genomic hybridization in pregnancy with major congenital malformations
Taiwan J Obstet Gynecol. 2011 Mar;50(1):85-94.
Chen CP, Su YN, Lin SY, Chang CL, Wang YL, Huang JP, Chen CY, Hung FY, Chen YY, Wu PC, Wang W. Source Department of Obstetrics and Gynecology, Mackay Memorial Hospital, Taipei, Taiwan; Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan; Department of Biotechnology, Asia University, Taichung, Taiwan; School of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung, Taiwan; Institute of Clinical and Community Health Nursing, National Yang-Ming University, Taipei, Taiwan; Department of Obstetrics and Gynecology, School of Medicine, National Yang-Ming University, Taipei, Taiwan.
OBJECTIVE: To report five cases of major congenital malformations associated with common aneuploidies detected by rapid aneuploidy diagnosis.
CASE REPORTS: The fetus in the first case presented cebocephaly, semilobar holoprosencephaly, and tetralogy of Fallot on ultrasound at 25 gestational weeks. Cordocentesis using multiplex ligation-dependent probe amplification to detect aneuploidies of chromosomes X, Y, 13, 18, and 21 in uncultured cord blood revealed three copies of all targets on chromosome 13 consistent with the diagnosis of trisomy 13. The fetus in the second case presented bilateral choroid plexus cysts, congenital diaphragmatic hernia, and club foot on ultrasound at 18 gestational weeks. Amniocentesis using array-based comparative genomic hybridization (aCGH) in uncultured amniocytes revealed a gain in the DNA dosage of chromosome 18 consistent with the diagnosis of trisomy 18. The fetus in the third case presented aortic stenosis and nuchal edema on ultrasound at 22 gestational weeks. Amniocentesis using aCGH in uncultured amniocytes revealed a result of monosomy X and Turner syndrome. The fetus in the fourth case presented nuchal cystic hygroma and ventriculomegaly on ultrasound at 17 gestational weeks. Amniocentesis using aCGH in uncultured amniocytes revealed a gain in the DNA dosage of chromosome 21 consistent with the diagnosis of trisomy 21. The fetus in the fifth case presented holoprosencephaly, omphalocele, and hydronephrosis on ultrasound at 17 gestational weeks. Amniocentesis using aCGH in uncultured amniocytes revealed a gain in the DNA dosage of chromosome 13 consistent with the diagnosis of trisomy 13.
CONCLUSIONS: Prenatal diagnosis of major congenital malformations should alert one to the possibility of chromosomal abnormalities. Multiplex ligation-dependent probe amplification and aCGH have the advantage of rapid aneuploidy diagnosis of common aneuploidies in cases with major congenital malformations.
Copyright © 2011. Published by Elsevier B.V.
BAC array CGH in patients with Velocardiofacial syndrome-like features reveals genomic aberrations on chromosome region 1q21.1
Our results confirmed aCGH as a successful strategy in order to characterize additional submicroscopic aberrations in patients with VCF-like features that fail to show alterations in 22q11.2 region. We report a 212-kb microduplication on 1q21.1, detected in two patients, which may contribute to CHD.