Abstract：
BACKGROUND:The recent discovery of the presence of circulating cell-free fetal DNA in maternal plasma opens up new prenatal diagnostic applications and provides new avenues for clinical investigation. It is of research and potential diagnostic interest to determine whether fetal trisomy 21 may be associated with quantitative abnormalities of circulating fetal DNA in maternal plasma. METHODS:Maternal plasma samples were prospectively collected from two centers situated in Hong Kong and Boston. Samples collected from Boston consisted of 7 women carrying male trisomy 21 fetuses, 19 carrying euploid male fetuses, and 13 carrying female fetuses. Samples collected from Hong Kong consisted of 6 women carrying male trisomy 21 fetuses, 18 carrying euploid male fetuses, and 10 carrying female fetuses. Male fetal DNA in maternal plasma was measured using real-time quantitative Y-chromosomal PCR. RESULTS:For patients recruited from Boston, the median circulating fetal DNA concentrations in women carrying trisomy 21 and euploid male fetuses were 46.0 genome-equivalents/mL and 23.3 genome-equivalents/mL, respectively (P = 0.028). For patients recruited from Hong Kong, the median circulating fetal DNA concentrations in women carrying trisomy 21 and euploid male fetuses were 48.2 genome-equivalents/mL and 16.3 genome-equivalents/mL, respectively (P = 0.026). None of the samples from women carrying female fetuses had detectable Y-chromosomal signals. CONCLUSIONS:Abnormally high concentrations of circulating fetal DNA are found in a proportion of women carrying fetuses with trisomy 21. The robustness and reproducibility of real-time PCR analysis of maternal plasma makes it a valuable tool for cross-institutional collaboration involving centers located in different parts of the world.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Lo YM,Lau TK,Zhang J,Leung TN,Chang AM,Hjelm NM,Elmes RS,Bianchi DWsubject
Has Abstractpub_date
1999-10-01 00:00:00pages
1747-51issue
10eissn
0009-9147issn
1530-8561journal_volume
45pub_type
临床试验,杂志文章,多中心研究abstract：BACKGROUND:Cardiovascular mortality is markedly higher in Russia than in Western Europe and the US. Little is known about indicators of atherosclerotic risk in the Russian population. To our knowledge, this is the first study of apolipoprotein (apo) AI and B in Russia based on the WHO-IFCC standard. METHODS:We measure...
journal_title：Clinical chemistry
pub_type： 杂志文章
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journal_title：Clinical chemistry
pub_type： 杂志文章
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更新日期：1990-01-01 00:00:00
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journal_title：Clinical chemistry
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更新日期：1982-01-01 00:00:00
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pub_type： 杂志文章
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pub_type： 杂志文章
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更新日期：2006-01-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 临床试验,杂志文章
doi：
更新日期：1991-07-01 00:00:00
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pub_type： 杂志文章
doi：
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更新日期：1996-05-01 00:00:00
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pub_type： 临床试验,杂志文章,多中心研究
doi：
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