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[Detection of a recurrent de novo mutation in a Chinese family affected with Duchenne muscular dystrophy].

OBJECTIVE
To provide genetic analysis for a family affected with Duchenne muscular dystrophy (DMD) with a recurrent de novo mutation.


METHODS
Multiplex ligation dependent probe amplification (MLPA) was used to detect potential deletion and duplication of the DMD gene, and the DNA products were sequenced on a Genetic Analyzer 3130 sequencer. Haplotype analysis was performed using four short tandem repeat polymorphism loci (44C/A, 45C/A, 49C/A and 63C/A) of the DMD gene for the family.


RESULTS
A same deletional mutation (Del 48-50) of the DMD gene was detected in the proband and fetus, but not in their mother. The proband and fetus have inherited the same haplotype of the DMD gene from their mother. The fetus was predicted to be affected by the disease.


CONCLUSION
Above findings suggested that the mother was very likely to have a germline mosaicism for the DMD gene mutation. For the de novo DMD mutation, although genetic analysis of peripheral blood DNA has indicated that the proband's mother was not a carrier, germline mosaicism could still not be ruled out, and prenatal gene diagnosis should be provided for subsequent pregnancies.