Biomaterial Database

Defining the role of fluorescence in situ hybridization on uncultured amniocytes for prenatal diagnosis of aneuploidies. 1997

M E D'Alton, and F D Malone, and D Chelmow, and B E Ward, and D W Bianchi

Department of Obstetrics and Gynecology, Tufts University School of Medicine, New England Medical Center, Boston, MA 02111, USA.

OBJECTIVE This study examines the role of fluorescence in situ hybridization on uncultured amniocytes for prenatal diagnosis in a population at high risk for aneuploidies. METHODS All patients undergoing amniocentesis for fetal structural abnormality on ultrasonographic examination (performed from 13 to 39 weeks), abnormal maternal serum aneuploidy screening results, or advanced maternal age with substantial parental anxiety were offered both fluorescence in situ hybridization on uncultured cells and conventional metaphase karyotyping on dividing cells. RESULTS From 1992 to 1995, 315 patients were studied. Mean time to obtain results was 2.8 days for fluorescence in situ hybridization and 8.3 days for karyotype. Fluorescence in situ hybridization was informative in 254 samples (80.6%), and within this group 21 aneuploidies were correctly identified. Among informative specimens there was 100% sensitivity and specificity, with 100% positive and negative predictive values. Of the 315 samples, 61 (19.4%) were uninformative or unreportable. Of 25 total cases of karyotype-proved aneuploidy, 4 were reported as uninformative by fluorescence in situ hybridization, for a total detection rate of 84%. Overall, amniocenteses performed after 24 weeks were significantly more likely to be uninformative than those performed in the second trimester (45% vs 16%, p = 0.01), peaking at a 56% uninformative rate after 33 weeks. Logistic regression analysis showed an 8% increase in the uninformative rate per week of gestational age (odds ratio 1.08, 95% confidence interval 1.04 to 1.14). CONCLUSIONS Fluorescence in situ hybridization on uncultured amniocytes is a rapid, clinically useful tool for prenatal diagnosis, with informative specimens being highly accurate. The combination of a structural fetal anomaly and an abnormal fluorescence in situ hybridization result should allow for definitive management decisions. The significant increase in uninformative specimens at later gestational ages limits its usefulness in the third trimester.

UI	MeSH Term	Description	Entries
D007621	Karyotyping	Mapping of the KARYOTYPE of a cell.	Karyotype Analysis Methods,Analysis Method, Karyotype,Analysis Methods, Karyotype,Karyotype Analysis Method,Karyotypings,Method, Karyotype Analysis,Methods, Karyotype Analysis
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D011247	Pregnancy	The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.	Gestation,Pregnancies
D011296	Prenatal Diagnosis	Determination of the nature of a pathological condition or disease in the postimplantation EMBRYO; FETUS; or pregnant female before birth.	Diagnosis, Prenatal,Fetal Diagnosis,Fetal Imaging,Fetal Screening,Intrauterine Diagnosis,Antenatal Diagnosis,Antenatal Screening,Diagnosis, Antenatal,Diagnosis, Intrauterine,Prenatal Screening,Antenatal Diagnoses,Antenatal Screenings,Diagnosis, Fetal,Fetal Diagnoses,Fetal Imagings,Fetal Screenings,Imaging, Fetal,Intrauterine Diagnoses,Prenatal Diagnoses,Prenatal Screenings,Screening, Antenatal,Screening, Fetal,Screening, Prenatal
D002869	Chromosome Aberrations	Abnormal number or structure of chromosomes. Chromosome aberrations may result in CHROMOSOME DISORDERS.	Autosome Abnormalities,Cytogenetic Aberrations,Abnormalities, Autosome,Abnormalities, Chromosomal,Abnormalities, Chromosome,Chromosomal Aberrations,Chromosome Abnormalities,Cytogenetic Abnormalities,Aberration, Chromosomal,Aberration, Chromosome,Aberration, Cytogenetic,Aberrations, Chromosomal,Aberrations, Chromosome,Aberrations, Cytogenetic,Abnormalities, Cytogenetic,Abnormality, Autosome,Abnormality, Chromosomal,Abnormality, Chromosome,Abnormality, Cytogenetic,Autosome Abnormality,Chromosomal Aberration,Chromosomal Abnormalities,Chromosomal Abnormality,Chromosome Aberration,Chromosome Abnormality,Cytogenetic Aberration,Cytogenetic Abnormality
D005260	Female		Females
D005333	Fetus	The unborn young of a viviparous mammal, in the postembryonic period, after the major structures have been outlined. In humans, the unborn young from the end of the eighth week after CONCEPTION until BIRTH, as distinguished from the earlier EMBRYO, MAMMALIAN.	Fetal Structures,Fetal Tissue,Fetuses,Mummified Fetus,Retained Fetus,Fetal Structure,Fetal Tissues,Fetus, Mummified,Fetus, Retained,Structure, Fetal,Structures, Fetal,Tissue, Fetal,Tissues, Fetal
D005865	Gestational Age	The age of the conceptus, beginning from the time of FERTILIZATION. In clinical obstetrics, the gestational age is often estimated from the onset of the last MENSTRUATION which is about 2 weeks before OVULATION and fertilization. It is also estimated to begin from fertilization, estrus, coitus, or artificial insemination.	Embryologic Age,Fetal Maturity, Chronologic,Chronologic Fetal Maturity,Fetal Age,Maturity, Chronologic Fetal,Age, Embryologic,Age, Fetal,Age, Gestational,Ages, Embryologic,Ages, Fetal,Ages, Gestational,Embryologic Ages,Fetal Ages,Gestational Ages
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000293	Adolescent	A person 13 to 18 years of age.	Adolescence,Youth,Adolescents,Adolescents, Female,Adolescents, Male,Teenagers,Teens,Adolescent, Female,Adolescent, Male,Female Adolescent,Female Adolescents,Male Adolescent,Male Adolescents,Teen,Teenager,Youths