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

• Published in: BioMed research international 2009-01, Vol.2009 (2009), p.1-8
• Main Authors: Tzeng, Ching-Cherng, Liou, Chiou-Ping, Li, Chien-Feng, Lai, Ming-Chi, Tsai, Li-Ping, Cho, Wei-Chen, Chang, Hui-Ting
• Format: Article
• Language: English
• Subjects: Accuracy; Biological and medical sciences; Blood Specimen Collection - methods; CpG Islands - genetics; Deoxyribonucleic acid; DNA; DNA Methylation; Fragile X Mental Retardation Protein - blood; Fragile X Mental Retardation Protein - genetics; Fragile X syndrome; Fragile X Syndrome - blood; Fragile X Syndrome - diagnosis; Fragile X Syndrome - genetics; Genes; Genetic testing; Humans; Male; Medical sciences; Mental retardation; Methodology Report; Methods; Methylation; Mutation; Pharmacology. Drug treatments; Polymerase chain reaction; Polymerase Chain Reaction - methods; Promoter Regions, Genetic - genetics; Reproducibility of Results; Sensitivity and Specificity; Studies
• ISSN: 1110-7243; 2314-6133; 1110-7251; 2314-6141
• DOI: 10.1155/2009/643692

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.