Table 2.

Differentially expressed genes based on placenta tissue preservation treatments across time. Nine possible patterns resulting from gene expression changes that could occur between early (0–60 min) and late collection (60–120 min) (t-test; P-value < 0.01).

Pattern	0-60 minutes (early response)	60-120 minutes (late response)	Annotation	1st Trimester			3rd Trimester
				RNAlater 1.1	RNAlater 1.2	Snap Freeze 1.1	RNAlater 3.1	RNAlater 3.2	Snap Freeze 3.1
1			Up, Up	0	13	1	1	2	4
2			Up, No Change	110	211	99	115	266	402
3			Up, Down	9	2	3	10	15	28
4			No Change, Up	460	326	187	48	297	111
5			No Change	26503 (95.6%)	26323 (94.9%)	27145 (97.9%)	27352 (98.6%)	26258 (94.7%)	26799 (96.6%)
6			No Change, Down	561	517	177	85	453	117
7			Down, Up	6	13	2	3	37	16
8			Down, No Change	62	232	104	105	389	242
9			Down, Down	8	82	1	0	2	0

Total probes: 27719