Duchenne and Becker Muscular Dystrophy: Contribution of a Molecular and Immunohistochemical Analysis in Diagnosis in Morocco

Abstract

Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) are X-linked recessive disorders caused by mutations of the DMD gene located at Xp21. In DMD patients, dystrophin is virtually absent; whereas BMD patients have 10% to 40% of the normal amount. Deletions in the dystrophin gene represent 65% of mutations in DMD/BMD patients. To explain the contribution of immunohistochemical and genetic analysis in the diagnosis of these dystrophies, we present 10 cases of DMD/BMD with particular features. We have analyzed the patients with immunohistochemical staining and PCR multiplex to screen for exons deletions. Determination of the quantity and distribution of dystrophin by immunohistochemical staining can confirm the presence of dystrophinopathy and allows differentiation between DMD and BMD, but dystrophin staining is not always conclusive in BMD. Therefore, only identification involved mutation by genetic analysis can establish a correct diagnosis.

Duchenne or Becker muscular dystrophy: A clinical, genetic and immunohistochemical study in China

“…Multiplex PCR has been used for a long period of time as the mutation screening method of choice to assess the deletion of selected exons in DMD. [17][18][19][20] Our study proved that a combination of MLPA with sequencing of the DMD gene, which could examine all 79 exons for deletion or duplication mutations, enabled a mutation detection rate of 70% in Chinese DMD/BMD cases. In addition, MLPA has been shown to detect mutations in close proximity to the ligation site of the MLPA probe, which has improved the detection rate of duplications of the DMD gene that have long been under-detected in patients.…”

Ocular findings in muscular dystrophies

“…(Mercuri and Muntoni, 2013) DMD has an unremitting and progressive course, and mainly affects males. (Bellayou et al 2009) Bellayou et al 2009) BMD is a less severe formof the disease and has a slower progression. Bellayou et al 2009, Aartsma-Rus et al2006, Chakkalakal et al 2005.DMD and BMD are Xlinked muscular dystrophies.…”

“…(Bellayou et al 2009) Bellayou et al 2009) BMD is a less severe formof the disease and has a slower progression. Bellayou et al 2009, Aartsma-Rus et al2006, Chakkalakal et al 2005.DMD and BMD are Xlinked muscular dystrophies. The incidence of DMD is around1 in 3,500 male births (2.9 per 10,000 males), whereas the incidence of BMDisaround1 in 18,518 male births (0.5 per 10,000 males).…”

Distrofinopati Hastalarının Demografik, Klinik ve Genetik Özellikleri: Tek Merkez Üçüncü Basamak Deneyimi

“…DMD/BMD mutasyonları genellikle delesyon (%60), veya duplikasyon (%5)'den kaynaklanmaktadır. Geriye kalan kısmı (%35), nokta mutasyonları ve küçük delesyon/ insersiyon mutasyonları oluşturmaktadır Genin, hot spot mutasyon bölgeleri, 3-7. ekzon ve 44-55. ekzondur (3,4).…”