Methyl-CpG-Binding PCR of Bloodspots for Confirmation of Fragile X Syndrome in Males

Table 1

Molecular testing of 1399 males suspected of having fragile X syndrome.

			Methylation (+)		Methylation (–)
	Screening PCR		SBH MB-PCR		SBH MB-PCR
Venous blood	Strong	219^§	0	0	219	60
	Weak	0
	Failed	10*	10	10	0	0
Bloodspot	Strong	1140
	Weak ^#	16*	2	2	14	14
	Failed ^#	14*	12	12	2	2
Total		1399	24	24	235	76

Methylation (+) and Methylation (–): presence and absence of methylated FMR1 promoter, respectively; SBH: Southern blot hybridization; MB-PCR: methyl-CpG-binding PCR; ^§: of which 60 cases were randomly selected for the blinded test; *: all cases included for the blinded test; ^#: SBH was performed using resubmitted venous blood samples.