Causation in cerebral palsy: Parental beliefs and associated emotions.

AIM: To better understand parents' beliefs about causation in cerebral palsy (CP) and the emotions related to those beliefs. METHOD: We surveyed 226 parents of children with CP aged 1 to 18 years, recruited from the Victorian Cerebral Palsy Register, to evaluate their beliefs about the causes of CP, including genetic causes, causes specific to their own child, and their attitudes and emotions in relation to these. RESULTS: Although 92% of participants reported that understanding the causes of their child's CP was important, uncertainty about the cause was expressed by 13%. The most frequently endorsed causal factors, in general and in their own child respectively, were intrapartum hypoxia (81%, 36%) or brain damage (69%, 22%), brain damage during pregnancy (73%, 28%), and preterm birth (66%, 28%). Genetic causes were deemed relevant by 13% of participants and hospital or professional error by 16%. Parents shared related feelings of anger (59%), sadness (80%), guilt (61%), and confusion (53%); parental anger was more likely when their child's CP was attributed to intrapartum events. INTERPRETATION: Substantial parental interest in understanding the causes of CP, together with uncertainty about the causes, parents' causal attributions, and significant emotional sequelae, highlight a strong need for provision of information and support for families of children recently diagnosed with CP. WHAT THIS PAPER ADDS: Understanding the causes of their child's cerebral palsy (CP) was important to parents. Parents most often endorsed intrapartum factors as a cause of CP. Parents reported experiencing strong emotions about the causes of their child's CP.

Informing a value care model: lessons from an integrated adult neurogenomics clinic.

BACKGROUND: Advances in genomics provide improved opportunities for diagnosis of complex neurogenetic disorders, yet the optimal approach to translate these benefits to the outpatient clinic is unclear. AIMS: We retrospectively reviewed referral indications and outcomes of an integrated multidisciplinary team (MDT) clinic pathway for adults with suspected neurogenetic disorders. The associated cost implications were estimated. METHODS: Consecutive patients who attended the neurogenomics clinic from January 2017 to April 2020 were included. The clinic comprised neurologists, clinical geneticists and genetic counsellors, who assessed each patient concurrently. RESULTS: Ninety-nine new patients were referred spanning 45 different clinical diagnoses. Following MDT clinical assessment, 23% (23/99) of referral diagnoses were revised prior to molecular testing. Eighty-one patients (82%) underwent genetic testing, including 43 exome-based panels, 15 whole-genome sequencing, 14 single gene tests, 27 repeat-primed polymerase chain reaction testing and two chromosomal microarrays. Overall, 33/99 patients (33%) received a diagnosis, either a molecular diagnosis (n = 24, of which 22 were diagnostic and two were predictive) or a clinical diagnosis (n = 9). Of the clinical diagnosis cohort, five patients received a diagnosis without molecular testing and four patients whose negative testing (one diagnostic and three predictive) allowed exclusion of genetic differentials and, hence, confirmation of clinical diagnoses. The diagnostic rate following MDT and diagnostic testing was 30% (28/94), excluding the five predictive testing cases. MDT assessment aligned with eventual molecular diagnoses in 96% of cases. The estimated average costs were AU$1386 per patient undergoing MDT assessment and AU$4159 per diagnosis achieved. CONCLUSIONS: We present an integrated multidisciplinary neurogenomics clinic pathway providing a diagnostic yield of 33% (30% excluding predictive testing cases), with costing implications. The relatively high diagnostic yield may be attributed to multidisciplinary input integrating accurate phenotyping of complex disorders and interpretation of genomic findings.

A novel synonymous KMT2B variant in a patient with dystonia causes aberrant splicing.

BACKGROUND: Heterozygous KMT2B variants are a common cause of dystonia. A novel synonymous KMT2B variant, c.5073C>T (p.Gly1691=) was identified in an individual with childhood-onset progressive dystonia. METHODS: The splicing impact of c.5073C>T was assessed using an in vitro exon-trapping assay. The genomic region of KMT2B exons 23-26 was cloned into the pSpliceExpress plasmid between exon 2 and 3 of the rat Ins2 gene. The c.5073C>T variant was then introduced through site-directed mutagenesis. The KMT2B wild-type and c.5073C>T plasmids were transfected separately into HeLa cells and RNA was extracted 48 hours after transfection. The RNA was reverse transcribed to produce cDNA, which was PCR amplified using primers annealing to the flanking rat Ins2 sequences. RESULTS: Sanger sequencing of the PCR products revealed that c.5073C>T caused a novel splice donor site and therefore a 5-bp deletion of KMT2B exon 23 in mature mRNA, leading to a coding frameshift and premature stop codon (p.Lys1692AsnfsTer7). CONCLUSION: To our knowledge, this is the first report of a KMT2B synonymous variant associated with dystonia. Reassessment of synonymous variants may increase diagnostic yield for inherited disorders including monogenic dystonia. This is of clinical importance, given the generally favourable response to deep brain stimulation for KMT2B-related dystonia.