Imprinting and Promoter Usage of Insulin-Like Growth Factor II in Twin Discordant Placenta

Table 3

Polymorphisms and imprinting of the IGF-II gene in placenta [n (%)].

Group	Polymorphisim			Imprinting
	𝑛	AA/BB∗	AB∗	𝑛	A/B∗∗	AB∗∗
T0 group	110	41 (37.3)	69 (62.7)	68	56 (82.4)	12 (17.6)
T1 group	34	15 (44.1)	19 (55.9)	19	16 (84.2)	3 (15.8)
T2 group	26	10 (38.5)	16 (61.5)	16	9 (56.2)	7 (43.8)^#

∗AA, BB, and AB are three different gene polymorphisms; AA/BB reflects homozygosity, and AB reflects heterozygosity. ∗∗A, B, and AB are three different imprinting states; A/B is the normal imprinting expression, while AB reflects loss of imprinting. In the T0 group, the imprinting status could not be detected in one case with AB gene polymorphism.# The frequency of loss of imprinting of the IGF-II gene was statistically significantly different between the T0 group and the T2 group, 𝑃=.035.