Targeted next generation sequencing reveals a novel intragenic deletion of the LAMA2 gene in a patient with congenital muscular dystrophy.

Mutations in the LAMA2 gene cause laminin α-2 (merosin)-deficient congenital muscular dystrophies, which are autosomal recessive muscle disorders. Laminin α-2 is widely expressed in the basement membrane of skeletal muscle, the myotendinous junctions and extra-synaptically at neuromuscular synapses. In the present study, target next-generation sequencing was used for mutation detection, and polymerase chain reaction (PCR) analysis and Sanger sequencing were used in the identification of small deletions. Subsequently, quantitative PCR (qPCR) was performed to characterize the identified deletion encompassing exon five of the LAMA2 gene. Two causative mutations were identified using target region sequencing which provided the additional information required to facilitate clinical diagnosis. One heterozygous mutation (p. Lys682LysfsX22) was identified and confirmed by Sanger sequencing, and another heterozygous mutation (Exon5del) was found and validated by qPCR. Co-segregation analysis indicated that the Exon5del mutation originated from the proband's mother and the previously reported frameshift mutation (p. Lys682LysfsX22) was inherited from the proband's father. To the best of our knowledge, the present study was the first to report an entire exon five deletion in the LAMA2 gene. [ABSTRACT FROM AUTHOR]