The Neurocognitive and Behavioral Profiles of 3 Brothers With Becker Muscular Dystrophy

Abstract

Becker muscular dystrophy patients generally carry in-frame mutations in the dystrophin gene, allowing the production of partially functional dystrophin protein. The presence of cognitive and behavioral comorbidities and the relation with the location of mutations has been scarcely investigated in Becker. This case report describes the neurocognitive and behavioral profiles of 3 brothers with Becker carrying an in-frame deletion of exons 45-48. The 3 cases underwent 2 consecutive neuropsychological assessments of which one assessment took place when they completed their primary education (age range of the cases: 11.2 -12.1 years). Intellectual abilities were normal to high and all cases had difficulties with processing speed and math. The brothers differed in intellectual abilities, executive functions, working memory, attention and reading abilities. Variability in cognitive development was noted as well. This report suggests that cognitive and behavioral functions in Becker vary regardless of gene mutation and exposer to similar environmental factors.

Wechsler Scale Intelligence Testing in Males with Dystrophinopathies: A Review and Meta-Analysis

“…Previous research has shown an association between the location of the dystrophin gene mutation, affecting specific dystrophin isoforms in the brain (i.e., Dp140 and Dp71), and cognitive impairments. However, the exact phenotype-genotype relationship in both DMD and BMD remains unclear [ 11 , 13 , 20 , 21 , 22 , 23 , 24 ]. The study by Cotton, Voudouris, and Greenwood, published in 2001 [ 25 ], was the first meta-analysis describing (impaired) intelligence in DMD.…”

“…We aim to give an update on the VIQ-PIQ split in DMD and BMD, as this is a clinically relevant split that is reformulated in the newest versions as verbal comprehension and perceptual organization. VIQ and PIQ in dystrophinopathies are still reported in recent studies [ 23 , 24 , 39 ].…”

Natural history of Becker muscular dystrophy: a multicenter study of 225 patients

“…5 Furthermore, patients with BMD, as well as DMD can develop central nervous system (CNS) disorders. 6,7 The association between the terminal portion pathogenic variants in DMD and CNS lesions has been demonstrated in DMD and BMD. [8][9][10] BMD can be suspected based on hyperCKemia in neonates, 11 leading to an increased number of diagnosed patients.…”

“…Early cardiac treatment can delay or slow the progression of cardiomyopathy, especially in patients with BMD having extra‐skeletal muscle involvement, although there have been cases of rapid deterioration of cardiac function due to delayed diagnosis caused by lack of awareness of rare neuromuscular diseases 5 . Furthermore, patients with BMD, as well as DMD can develop central nervous system (CNS) disorders 6,7 . The association between the terminal portion pathogenic variants in DMD and CNS lesions has been demonstrated in DMD and BMD 8–10 …”