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Methyl-CpG-binding PCR of bloodspots for confirmation of fragile X syndrome in males.

ABSTRACT: This study demonstrates that methyl-CpG-binding PCR (MB-PCR) is a rapid and simple method for detecting fragile X syndrome (FXS) in males, which is performed by verifying the methylation status of the FMR1 promoter in bloodspots. Proteins containing methyl-CpG-binding (MB) domains can be freeze-stored and used as stocks, and the entire test requires only a few hours. The minimum amount of DNA required for the test is 0.5 ng. At this amount, detection sensitivity is not hampered, even mixing with excess unmethylated alleles up to 320 folds. We examined bloodspots from 100 males, including 24 with FXS, in a blinded manner. The results revealed that the ability of MB-PCR to detect FMR1 promoter methylation was the same as that of Southern blot hybridization. Since individuals with 2 or more X chromosomes generally have methylated FMR1 alleles, MB-PCR cannot be used to detect FXS in females.

SUBMITTER: Tzeng CC

PROVIDER: S-EPMC2773378 | biostudies-literature | 2009

REPOSITORIES: biostudies-literature

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Methyl-CpG-binding PCR of bloodspots for confirmation of fragile X syndrome in males.

Tzeng Ching-Cherng CC Liou Chiou-Ping CP Li Chien-Feng CF Lai Ming-Chi MC Tsai Li-Ping LP Cho Wei-Chen WC Chang Hui-Ting HT

Journal of biomedicine & biotechnology 20091104

This study demonstrates that methyl-CpG-binding PCR (MB-PCR) is a rapid and simple method for detecting fragile X syndrome (FXS) in males, which is performed by verifying the methylation status of the FMR1 promoter in bloodspots. Proteins containing methyl-CpG-binding (MB) domains can be freeze-stored and used as stocks, and the entire test requires only a few hours. The minimum amount of DNA required for the test is 0.5 ng. At this amount, detection sensitivity is not hampered, even mixing with ...[more]

PMID: 19893637

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