Human Reproduction Update, Vol.8, No.6 pp.493-500, 2002
© European Society of Human Reproduction and Embryology 2002; all rights reserved
Cell-free fetal DNA and intact fetal cells in maternal blood circulation: implications for first and second trimester non-invasive prenatal diagnosis
1 Departments of Obstetrics and Gynecology, 2 Molecular and Human Genetics, 3 Immunology, Baylor College of Medicine, Houston, Texas, USA
To whom correspondence should be addressed at: Farideh Z. Bischoff, 6550 Fannin St, Baylor College of Medicine, Department of Obstetrics & Gynecology, Houston, TX 77030, USA; e-mail: bischoff{at}bcm.tmc.edu
Abstract
Both intact fetal cells as well as cell-free fetal DNA are present in the maternal circulation and can be recovered for non-invasive prenatal genetic diagnosis. Although methods for enrichment and isolation of rare intact fetal cells have been challenging, diagnosis of fetal chromosomal aneuploidy including trisomy 21 in first- and second-trimester pregnancies has been achieved with a 50–75% detection rate. Similarly, cell-free fetal DNA can be reliably recovered from maternal plasma and assessed by quantitative PCR to detect fetal trisomy 21 and paternally derived single gene mutations. Real-time PCR assays are robust in detecting low-level fetal DNA concentrations, with sensitivity of approximately 95–100% and specificity near 100%. Comparing intact fetal cell versus cell-free fetal DNA methods for non-invasive prenatal screening for fetal chromosomal aneuploidy reveals that the latter is at least four times more sensitive. These preliminary results do not support a relationship between frequency of intact fetal cells and concentration of cell-free fetal DNA. The above results imply that the concentration of fetal DNA in maternal plasma may not be dependent on circulating intact fetal cells but rather be a product of growth and cellular turnover during embryonic or fetal development.
Key words: cell-free fetal DNA in maternal plasma / fetal cells in maternal blood / fetal chromosomal aneuploidy / non-invasive prenatal diagnosis / real-time quantitative PCR
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  C. J. Jorgez, D. D. Dang, R. Wapner, A. Farina, J. L. Simpson, and F. Z. Bischoff Elevated levels of total (maternal and fetal) beta-globin DNA in maternal blood from first trimester pregnancies with trisomy 21 Hum. Reprod., August 1, 2007; 22(8): 2267 - 2272. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 F. Z. Bischoff, D. E. Lewis, and J. L. Simpson Cell-free fetal DNA in maternal blood: kinetics, source and structure Hum. Reprod. Update, January 1, 2005; 11(1): 59 - 67. [Abstract] [Full Text] [PDF]
|
|