Early versus late diagnosis of LAMA2 congenital muscular dystrophy: a distinct consequence

Laminin subunit alpha 2 (LAMA2)-related muscular dystrophy (LAMA2 MD) is caused by homozygous or compound heterozygous mutations in LAMA2 (OMIM#156225), located on chromosome 6q22.

We describe two patients with LAMA2 MD treated at a Taiwanese hospital. Both presented with gradual hypotonia starting in early infancy. A targeted muscular dystrophy/myopathy panel and whole-exome sequencing were used as diagnostic tools in both patients. In Patient 1, a maternally inherited variant (NM_000426.3:c.7525_7528dupCTCA/ p.Ser2510ThrfsTer3) and a paternally inherited variant (c.112 + 2 T > C) were revealed. In Patient 2, compound heterozygote mutations in LAMA2 were identified: 1) c.1583dupA(p.S529Efs*18) in exon 11, inherited paternally, and 2) c.A6931T:p.K2311X in exon 49, inherited maternally. The discovery of these four mutations enriches the genetic spectrum of LAMA2 MD.

We suggest that comprehensive genetic investigations be performed as early as possible in patients with suspected muscular dystrophy to provide appropriate treatment.