Table 3. ABO methylation analysis in patient specimens with ABO allelic loss of expression.

ID	DIAGNOSIS	GENO	EXP	METH
F9	AML	A1O1	little A1	U
F10	MDS	A1O1	loss of A1 & O	M
F11	AML M1	A1O1	loss of A1	U
F15	CML blast crisis	A1A2	No loss	M
F17	MDS	A1O1	No loss	U
F20	CML	A1O1	No loss	U
F23	CML chronic	A2B	No loss	U
F24	AML	BO1	No loss	U
F27	AML M4	A1O1	loss of A1	M
F30	CML chronic	BO1	No loss	U
F39	AML M4	A2O1	loss of A2	M
F51	AML M4	A1O1	No loss	U
F53	AML M1	A1O1	loss of A1	M
F57	AML M7	BO1	No loss	U
F60	CML blast crisis	A1A2	'93+'96–	M

In the ID column a F prefix denotes patients analyzed by flow cytometry while a S prefix denotes loss of ABH antigen patients as detected by serology. ‘GENO’ refers to ABO genotype, ‘METH’ to ABO promoter CpG island methylation assessed either by MS-SSCA, COBRA and/or melt curve analysis (MCA). ‘U’ unmethylated at the ABO promoter and ‘M’ is methylated at the ABO promoter. For patient F60 two samples were available for analysis; the 1993 ('93) sample was positive for ABO expression whereas the 1996 ('96) sample was negative for ABO expression.