RESUMO
Phosphomannomutase deficiency (PMM2-CDG) leads to cerebellar atrophy with ataxia, dysmetria, and intellectual deficits. Despite advances in therapy, the cognitive and adaptive profile remains unknown. Our study explores the adaptive profile of 37 PMM2-CDG patients, examining its association with parental stress and medical characteristics. Assessment tools included ICARS for the cerebellar syndrome and NPCRS for global disease severity. Behavioral and adaptive evaluation consisted of the Vineland Adaptive Behavior Scale and the Health of the Nation Outcome Scales. Psychopathological screening involved the Child Behavior Checklist and the Symptom Check-List-90-R. Parental stress was evaluated using Parental Stress Index. Results were correlated with clinical features. No significant age or sex differences were found. 'Daily living skills' were notably affected. Patients severely affected exhibited lower adaptive skill values, as did those with lipodystrophy and inverted nipples. Greater severity in motor cerebellar syndrome, behavioral disturbances and the presence of comorbidities such as hyperactivity, autistic features and moderate-to-severe intellectual disability correlated with greater parental stress. Our study found no decline in adaptive abilities. We provide tools to assess adaptive deficits in PMM2-CDG patients, emphasizing the importance of addressing communication, daily living skills, and autonomy, and their impact on parental stress in clinical monitoring and future therapies.
Assuntos
Ataxia Cerebelar , Doenças Cerebelares , Criança , Humanos , Masculino , Feminino , Estudos Transversais , Doenças Cerebelares/diagnóstico , PaisRESUMO
The number of genes implicated in neurodevelopmental conditions is rapidly growing. Recently, variants in PPP2R1A have been associated with syndromic intellectual disability and a consistent, but still expanding, phenotype. The PPP2R1A gene encodes a protein subunit of the serine/threonine protein phosphatase 2A enzyme, which plays a critical role in cellular function. We report an individual showing pontocerebellar hypoplasia (PCH), microcephaly, optic and peripheral nerve abnormalities, and an absence of typical features like epilepsy and an abnormal corpus callosum. He bears an unreported variant in an atypical region of PPP2R1A. In silico studies, functional analysis using immunofluorescence, and super-resolution microscopy techniques were performed to investigate the pathogenicity of the variant. This analysis involved a comparative analysis of the patient's fibroblasts with both healthy control cells and cells from an individual with the previously described phenotype. The results showed reduced expression of PPP2R1A and the presence of aberrant protein aggregates in the patient's fibroblasts, supporting the pathogenicity of the variant. These findings suggest a potential association between PPP2R1A variants and PCH, expanding the clinical spectrum of PPP2R1A-related neurodevelopmental disorder. Further studies and descriptions of additional patients are needed to fully understand the genotype-phenotype correlation and the underlying mechanisms of this novel phenotype.