Maternal serum cell-free fetal DNA levels are increased in cases of trisomy 13 but not trisomy 18
Maternal serum cell-free fetal DNA levels are increased in cases of trisomy 13 but not trisomy 18
复制标题
13 三体性病例的母体血清游离胎儿 DNA 水平升高，但 18 三体性病例则不然
作者：
T. Wataganara;Erik S. Leshane;A. Farina;G. Messerlian;Thomas Lee;J. Canick;D. Bianchi
抽象。母体循环中的游离胎儿DNA是胎儿非整倍体的潜在非侵入性标记。在以前的研究中，Y DNA作为胎儿特异性标志物，循环胎儿DNA水平被证明是升高的妇女携带三体21胎儿。本研究的目的是确定携带13或18三体胎儿的孕妇血清中游离胎儿DNA水平是否也升高。研究了5例男性13三体和5例男性18三体的存档母体血清样品。每个病例的胎儿性别、胎龄和冷冻储存时间与新生儿病历审查后推测为整倍体的四个或五个对照血清样本相匹配。实时定量聚合酶链反应扩增的DYS 1进行测量男性胎儿DNA的量存在。未校正的血清胎儿DNA浓度中位数为97.5 GE/ml（每毫升基因组当量; 29.2-187.0）的三体性13例，31.5 GE/ml（18.6-77.6）的三体性18例，和40.3 GE/ml（3.7-127.4）的控制。通过对每个匹配集内的值的等级进行方差分析，13三体病例中的胎儿DNA水平显著升高（P=0.016）。而18三体患者的胎儿DNA水平与对照组相比无显著性差异（P=0.244）。目前用于筛查的孕中期母体血清分析物不能识别13三体高风险胎儿。胎儿DNA可能有助于非侵入性筛查三体13提供了一个性别无关的胎儿DNA标记可以开发。
Abstract. Cell-free fetal DNA in the maternal circulation is a potential noninvasive marker for fetal aneuploidies. In previous studies with Y DNA as a fetal-specific marker, levels of circulating fetal DNA were shown to be elevated in women carrying trisomy 21 fetuses. The goal of this study was to determine whether cell-free fetal DNA levels in the serum of pregnant women carrying fetuses with trisomies 13 or 18 are also elevated. Archived maternal serum samples from five cases of male trisomy 13 and five cases of male trisomy 18 were studied. Each case was matched for fetal gender, gestational age, and duration of freezer storage to four or five control serum samples presumed to be euploid after newborn medical record review. Real-time quantitative polymerase chain reaction amplification of DYS1 was performed to measure the amount of male fetal DNA present. Unadjusted median serum fetal DNA concentrations were 97.5 GE/ml (genomic equivalents per milliliter; 29.2–187.0) for the trisomy 13 cases, 31.5 GE/ml (18.6–77.6) for the trisomy 18 cases, and 40.3 GE/ml (3.7–127.4) for the controls. Fetal DNA levels in trisomy 13 cases were significantly elevated (P=0.016) by analysis of variance of the ranks of values within each matched set. In contrast, fetal DNA levels in trisomy 18 cases were no different from the controls (P=0.244). Second trimester maternal serum analytes currently used in screening do not identify fetuses at high risk for trisomy 13. Fetal DNA may facilitate noninvasive screening for trisomy 13 provided that a gender-independent fetal DNA marker can be developed.