A noninvasive method for the detection of foetal DNA in early pregnancy based on differential methylation pattern of Ras association domain family member 1A

Figures & data

Table 1. Primers and probes of qPCR.

Target	Name	Sequence	Primer/probe
RASSF1A	RASSF1A-F	5′-AGC CTG AGC TCA TTG AGC TG-3′	Forward primer
RASSF1A	RASSF1A-R	5′-ACC AGC TGC CGT GTG G-3′	Reverse primer
RASSF1A	RASSF1A-P	5′-FAM-CCA ACG CGC TGC GCA T(MGB)-3′	Probe
β-Actin	ACTB-Y-F1	5′-GCG CCG TTC CGA AAG TT-3′	Forward primer
β-Actin	ACTB-Y-R1	5′-CGG CGG ATC GGC AAA-3′	Reverse primer
β-Actin	ACTB-Y-P1	5′-VIC-ACC GCC GAG ACC GCG TC(MGB)-3′	Probe
β-Actin	ACTB-N-F2	5′-GCA TCC CCC AAA GTT CAC-3′	Forward primer
β-Actin	ACTB-N-R2	5′-CGC ATC TCA TAT TTG GAA TGA C-3′	Reverse primer
β-Actin	ACTB-N-P2	5′-ROX-GTG GCC GAG GAC TTT GAT TGC(BHQ)-3′	Probe

Figure 1. The standard curves of RASSF1A.

Plot of the input target cell ntunbers (natural logaritlun) against the threshold cycle (Ct) of RASSF1A. Linear function is y = -0.7139 * x + 27. 891. The correlation coefficient is 0.9981.

Table 2. Quantitation of the foetal cells in IUL samples.

Sample ID	Age (weeks and day of gestation)	Foetalcells numbers	Foetalcells in total cells
L19	9.6	12959	0.14%
L23	7.6	10313	0.08%
L25	10.3	21361	0.24%
L26	9.1	13052	0.12%
L27	12.0	13624	0.10%
L29	11.7	9069	0.05%
L30	12.0	31860	0.39%
L31	8.9	28624	0.16%
L33	9.6	11643	0.06%
L35	11.0	13146	0.04%
L36	10.7	23946	0.12%
Average	10.2	17236	0.14%
Standard Deviation	1.3	7490	0.10%

Figure 2. EVTs express HLA-G and GATA-3 in IUL samples.

(A, B) HLA-G immunohistochemical staining in EVTs from IUL sample at gestational week 9.6. (C) The immunofluorescence merge figure of EVTs from IUL sample at gestational week 9.6. (D) DAPI staining for nucleus. (E) HLA-G and (F) GATA-3. Magnification: 100X, scale bar = 50 µm.

Data availability statement

The data that support the findings of this study are available on doi: 10.6084/m9.figshare.23633739