Spinal muscular atrophy due to a “de novo” 1.3Mb deletion: Implication for genetic counseling

• Published in: Neuromuscular disorders : NMD Vol. 23; no. 5; pp. 388 - 390
• Main Authors: da Silva, Luciana Rodrigues Jacy, Colovati, Mileny Esbravatti Stephano, Coprerski, Bruno, de Andrade, Carlos Eugênio Fernandez, Zanoteli, Edmar, Raskin, Salmo, Oliveira, Mariana Moysés, Melaragno, Maria Isabel, Perez, Ana Beatriz Alvarez
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-05-2013
• Subjects: Genetic counseling; SMN gene; SNP array; Spinal muscular atrophy; Genetic counseling; SNP array; Spinal muscular atrophy; SMN gene
• ISSN: 0960-8966; 1873-2364
• DOI: 10.1016/j.nmd.2013.01.009

We report a 3-year-old female with type I spinal muscular atrophy (SMA) born to a young and non-consanguineous couple. The child presented at two months of life with intense muscle weakness affecting predominantly proximal portions of the limbs, especially the legs, muscle hypotonia, fasciculation of the tongue, and severe respiratory muscle involvement. She remained in an intensive care unit with an assisted ventilation system from the fourth month of life. She died at 3years of age from pulmonary infection. Molecular analysis confirmed the diagnosis of SMA but revealed that only the father was an asymptomatic carrier. Because SMN1 is mapped in a complex region containing repetitive elements due to an inverted duplication of approximately 500kb, we carry out an SNP array and detected a 1.3Mb deletion including the SMN1 and SMN2 genes that explain the disease.