Detection of heterozygous deletions and duplications in the MECP2 gene in Rett syndrome by Robust Dosage PCR (RD-PCR).
Fifty to eighty percent of Rett syndrome (RTT) cases have point mutations in the gene encoding methyl-CpG-binding protein-2 (MECP2). A fraction of MECP2 negative classical RTT patients has large heterozygous deletions. Robust Dosage PCR (RD-PCR) assays were developed as a rapid, convenient and accurate method to detect large heterozygous deletions and duplications. A blinded analysis was performed for 65 RTT cases from Portugal by RD-PCR in the coding exons 2-4 of the MECP2 gene. Neither the patients with point mutations nor the non-classical RTT patients without point mutation had a deletion or duplication. One of remaining eight female patients with classical RTT without point mutation had a heterozygous deletion. This is the first report of a deletion spanning the entire MECP2 gene. The deletion was confirmed by Southern blotting analysis and the deletion junction was localized 37 kb upstream from exon 1 and 18 kb downstream from exon 4. No duplications were detected. Our results suggest that RD-PCR is an accurate and convenient molecular diagnostic method.
Shi
Jinxiu
J
Department of Molecular Genetics and Molecular Diagnosis, City of Hope National Medical Center, Duarte, California 91010-3000, USA.
Shibayama
Akane
A
Liu
Qiang
Q
Nguyen
Vu Q
VQ
Feng
Jinong
J
Santos
Mónica
M
Temudo
Teresa
T
Maciel
Patricia
P
Sommer
Steve S
SS
D015139:Blotting, Southern; D004252:DNA Mutational Analysis; D005260:Female; D017353:Gene Deletion; D020440:Gene Duplication; D006580:Genetic Carrier Screening / Q000379:methods; D006579:Heterozygote; D006801:Humans; D051783:Methyl-CpG-Binding Protein 2 / Q000235:genetics*; D016133:Polymerase Chain Reaction / Q000379:methods*; D015518:Rett Syndrome / Q000175:diagnosis / Q000235:genetics*
C497392:MECP2 protein, human; D051783:Methyl-CpG-Binding Protein 2