The spectrum of deletions and duplications in the dystrophin (DMD) gene in a cohort of patients with Duchenne muscular dystrophy in Sri Lanka.

BACKGROUND

Duchenne muscular dystrophy (DMD), which affects 1 in 3500 newborn males, is the most common fatal neurodegenerative disorder in children. Deletions and duplications in the DMD gene are the most common underlying etiological factors.

MATERIALS AND METHODS

Fifty consecutive children with DMD were screened for deletions and duplications in the DMD gene using Multiple Ligation-binding Probe Amplification (MLPA).

RESULTS

Forty (80%) children had deletions and 4 (8%) had duplications. Single exon involvement was seen in 8 (16%), two exon involvement was seen in 3 (6%), three exon involvement was seen in 6 (12%) children, and four exon involvement in 1 (2%) child. More than four exon involvement were seen in 26 (52%) children. The most common deletion was the deletion spanning from exon 45 to exon 52, which was seen in 6 (12%) children. The next common exon deletion was single exon 45 deletion seen in 4 (8%) children. The most frequent mutant region fell within exons 45 to 55 (52%) followed by within exons 21 to 44 (26%) and exons 1 to 20 (26%). The least common region fell within exons 56 to 79 (4%).

CONCLUSION

The deletion/duplication pattern seen in this cohort of children with DMD was similar to that reported among other global populations.