ABSTRACT
OBJECTIVE: Array technology in chorionic villus sampling (CVS) - analysis of clinical benefit and a proposal of a more effective 1st trimester genetic testing policy. DESIGN: Retrospective study. SETTING: Gennet, Center of Medical Genetics and Reproductive Medicine, Prague. MATERIAL AND METHODS: Total of 913 CVS were performed at Gennet between 2010-2014. All 913 samples were tested by QF-PCR rapid test for aneuploidy of chromosomes 13, 18, 21, X and Y and karyotyping following standard long term culture. Microarray analysis (Illumina HumanCytoSNP12 v2.1) was performed on 179 samples with normal result from both - QF-PCR and karyotyping. RESULTS: At 229 samples the common chromosomal aneuploidy was detected using rapid QF-PCR (25% from 911 successful rapid tests). Conventional karyotyping revealed 239 unbalanced chromosome aberrations (27% from 897 successful cultivations). 227/239 (95%) positive karyotypes confirmed QF-PCR finding of common aneuploidies. 10 unbalanced chromosome aberrations were not covered by rapid QF-PCR test. Microarray analysis of samples with normal result from both- QF-PCR and karyotyping- revealed 13 clinically relevant chromosome aberrations (7.5%). CONCLUSION: New policy for chorionic villi testing at Gennet was established. Based on evaluation of the results of karyotyping, array and QF-PCR and analysis of published data we decided to replace karyotyping by microarray analysis in all cases of foetuses with normal results from QF-PCR. More effective detection of pathological and clinically relevant chromosome aberrations in examined foetuses is expected.
Subject(s)
Chromosome Disorders/diagnosis , Karyotyping/methods , Prenatal Diagnosis/methods , Aneuploidy , Chorionic Villi Sampling , Female , Humans , Polymerase Chain Reaction/methods , Predictive Value of Tests , Pregnancy , Pregnancy Trimester, First , Retrospective StudiesABSTRACT
OBJECTIVES: SNP array (array method using Single Nucleotide Polymorphisms) enables to detect cytogenetically undetectable submicroscopic alterations (microdeletions, microduplications), which could be also causative for ultrasonographic anomalies of fetus. This article describes the principle, advantages, disadvantages and application possibilities of the SNP array method in prenatal diagnosis. The ten month experience with SNP array use in prenatal diagnosis is presented. DESIGN: Prospective study. SETTINGS: Gennet, Prague. MATERIAL AND METHODS: During the period from April 2010 to January 2011 we performed 110 SNP array analyses of fetal DNA: 14 chorionic villi samples (CVS), 88 amniotic fluid samples (AMC), 1 cord blood sample and 7 miscarriage samples. Laboratory tests were carried out on DNA from both cultured and uncultured fetal cells. Examinations were performed in fetuses with sonographic abnormal findings having normal karyotype. In addition 14 fetal cytogenetic abnormalities were solved. SNP array analysis was performed using Illumina InfiniumHD HumanCytoSNP-12 chip. All data were analysed by Illumina KaryoStudio and GenomeStudio software. RESULTS: SNP array analysis was performed in 108 fetuses (only 2 examination failures, 1.8%). In total, we detected CNV (copy number variation) in 29 samples (29/108 = 27%). 15% (16/108) of fetuses with abnormal ultrasound findings were found to carry clinically relevant CNV. Probably benign CNVs were found in 8 samples (8/108 = 7%) and in additional 5 CNVs parental samples have not been analysed yet. Excluding karyotypically abnormal cases clinically relevant CNVs were found in 10% of fetuses (9/94). In all cases with de novo chromosomal aberration the clinical relevancy was clarified (imbalances in 50%). CONCLUSION: Our data suggest that SNP array analysis is a relevant and useful technique in prenatal diagnosis.
Subject(s)
Congenital Abnormalities/diagnosis , Oligonucleotide Array Sequence Analysis , Polymorphism, Single Nucleotide , Prenatal Diagnosis , Congenital Abnormalities/diagnostic imaging , Congenital Abnormalities/genetics , Female , Humans , Pregnancy , Ultrasonography, PrenatalABSTRACT
In 1999-2000 at the Medical Clinic Motol Faculty Hospital in collaboration with the Gynaecological Clinic of the Hospital a group of 55 pregnant women with the diagnosis of gestational diabetes (GDM) were followed up. The objective of the investigation was to find out how in the investigated area (detachment area of the Gynaecological and Obstetric Clinic Motol Faculty Hospital) GDM is diagnosed at present, how it is treated and what is the percentage of perinatal morbidity in the investigated group. The mean age of the investigated women was 32.3 +/- 4.5 years. The presence of risk factors for the development of GDM was found in 59.8% of the examined women. 65.7% women had a positive gynaecological case-history. GDM was detected most frequently during the 30th week of pregnancy, in 25% women in the 35th and later week of gestation. In 52% the diagnosis of GDM was established only on hospital admission on account of complications of pregnancy. The mean HbA1C level during detection of gestational diabetes was 6.81 +/- 0.41%. The majority of women -91.1%--were treated by diet, 8.9% women had insulin treatment. The prevalence of diabetic foctopathy was 48.3%. The mean weight of the offspring of diabetic mothers was 3350 g +/- 248 g, the mean length was 49.6 +/- 6.3 cm. No stillbirth was recorded. One infant suffered from an inborn developmental defect (morbus Down). The results provide evidence not only of late diagnosis of GDM (after the 28th week of gestation) but also of inadequate screening in the field, as GDM is frequently detected only during complications of pregnancy.
