Boys with Duchenne muscular dystrophy (DMD) have a higher risk than the general population of having an intellectual disability, according to a new study published in the journal Plos One.
The risk of intellectual disability seems to be higher in patients who have a mutation at the 3’ end of the DMD gene, which disrupts Dp71, the smallest product from the gene.
To describe the cognitive and neurodevelopmental profiles of patients with DMD and explore underlying genotype-phenotype associations in these patients, a team of researchers, led by Kristy Iskandar from the Universitas Gadjah Mada in Yogyakarta, Indonesia, conducted a cross-sectional study involving 51 patients with DMD. Patients were between 5 and 18 years of age.
Read more about DMD comorbidities
The researchers used whole exome sequencing to determine the type of mutation the patients had. They measured the cognitive and adaptive function of the patients with the Wechsler Intelligence Scale for Children and the Vineland Adaptive Behavior Scales. They also used the Autism Mental Status Exam to screen for autism spectrum disorder and the Abbreviated Conner’s Rating Scale to screen for attention-deficit/hyperactivity disorder (ADHD).
The results showed that the mean total IQ score of patients with DMD was lower than the general population, with the boys who had a mutation disrupting Dp71 having the lowest IQ score.
Intellectual disability was seen in 15 patients. However, no patients had autism spectrum disorder, and only 4 (7.8% of all patients) had ADHD.
The authors concluded that Dp71 disruption may not be associated with autism spectrum or ADHD.
DMD is caused by a mutation in the DMD gene, which encodes the dystrophin protein. Dystrophin is vital for maintaining muscle health. It also plays an important role within the central nervous system, and the disease is often associated with brain-related comorbidities.
Iskandar K, Triono A, Sunartini, et al. Dp71 and intellectual disability in Indonesian patients with Duchenne muscular dystrophy. PLoS One. Published online October 31, 2022. doi:10.1371/journal.pone.0276640