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

Table 1

Detail description of phenotype discordant in T2 group.

No.	Chorion	Twin A			Twin B
		Abnormity	PM*	I^∗∗	Abnormity	PM^∗	I^∗∗
1	MCMA	Transposition of the great vessels, ventricular septal defect	AB	AB	N	AB	AB
2	DCDA	Mass on right back	AB	AB	N	AB	B
3	DCDA	Hydatidiform mole	AB	AB	N	AB	A
4	DCDA	Intrauterine death	AB	AB	N	AB	B
5	DCDA	Anencephaly, spinal bifida, omphalocele	AB	AB	N	BB
6	MCDA	Thoracogastroschisis, ventricular septal defect, aortic overriding	AB	AB	N	AB	B
7	DCDA	Fetal hydrops	AB	A	N	AA
8	DCDA	Hypospadias	AB	A	N	AA
9	DCDA	Abdominal-wall defect, spinal bifida	AB	A	N	BB
10	DCDA	Double outlet right ventricle	AB	B	N	AB	B
11	DCDA	Omphalocele	AA		N	AA
12	MCDA	Acardiac twin	AA		N	AA
13	MCDA	Hypospadias	AA		N	AA

∗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. Abbreviations: Polymorphisim (PM), Imprinting (I), monochorionic monoamniotic twin (MCMA), dichorionic diamniotic twin (DCDA), monochorionic diamniotic twin (MCDA), and normal (N).