Madrigal Bajo Irene, Jodar Bifet Meritxell, Badenas Orquin Celia
Service of Biochemistry and Genetics, Clinical Hospital of Barcelona and FCRB-Institute of Biomedical Research August Pi I Sunyer (IDIBAPS), Barcelona, Spain.
Rare Diseases Networking Biomedical Research Centre (CIBERER), Barcelona, Spain.
Adv Lab Med. 2025 Mar 25;6(2):135-143. doi: 10.1515/almed-2025-0055. eCollection 2025 Jun.
Circulating cell-free DNA (cfDNA) consists of extracellular DNA fragments that circulate in the bloodstream and derived from apoptotic cells such as hematopoietic cells or placental trophoblast cells during pregnancy.
cfDNA screening has been included in prenatal screening programs for the detection of chromosomal abnormalities. Unlike other invasive techniques, such as amniocentesis or chorionic villus sampling, cfDNA screening only requires a maternal plasma test. The use of advanced technologies for cfDNA testing, including DNA sequencing and SNP arrays, enables the detection of pregnancies at risk for trisomy 21, 18 or 13.
This test has demonstrated a high accuracy and reliability, with detection rates exceeding 99 % for trisomy 21, and a very low rate of false-positive and false-negative results. In some countries, cfDNA screening has already been integrated in combined or universal prenatal screening programs.
As new technologies emerge and become widely available, more accurate prenatal tests will be developed for other genetic abnormalities.
循环游离DNA（cfDNA）由在血液中循环的细胞外DNA片段组成，这些片段来源于凋亡细胞，如造血细胞或孕期胎盘滋养层细胞。
cfDNA筛查已被纳入产前筛查项目，用于检测染色体异常。与羊膜穿刺术或绒毛取样等其他侵入性技术不同，cfDNA筛查仅需进行母体血浆检测。采用包括DNA测序和单核苷酸多态性（SNP）阵列在内的先进技术进行cfDNA检测，能够检测出有21三体、18三体或13三体风险的妊娠。
该检测已证明具有高准确性和可靠性，21三体的检测率超过99%，假阳性和假阴性结果的发生率极低。在一些国家，cfDNA筛查已被纳入联合或通用的产前筛查项目。
随着新技术的出现和广泛应用，将开发出针对其他基因异常的更准确的产前检测方法。
