RESUMEN
22q11 deletion syndrome (22q11DS) is a genetic syndrome, prevalence around 1:4000-1:6000 live births, with a complex array of associated features, impacting on healthcare and educational support. This study reports the perceptions of families and individuals with 22q11DS in relation to these needs. Individuals and families of those with 22q11DS were approached though two national charities - the Max Appeal and 22Crew. An initial observational survey design was used to gather views via questions probing access to healthcare and educational experiences. Thirty-four responses were received and the data subjected to descriptive analysis. Over half of the respondents were diagnosed before the age of 1. Ninety-one percent reported ongoing difficulties with learning at school, compounded by school attendance being compromised as a result of medical interventions. Individuals reported engaging heavily with educational support and a high number of health professions (mean 9.5; mode 10). Age of diagnosis of 22q11DS ranged from birth to nine years. Families had ongoing concerns about aspects of education and healthcare services, and lack of knowledge and awareness of the difficulties faced by individuals with 22q11DS was raised. Healthcare and education providers should be aware of the range of services individuals required on a regular basis so as to provide a more holistic approach to care.
Asunto(s)
Síndrome de Deleción 22q11/psicología , Atención a la Salud/métodos , Padres/educación , Padres/psicología , Síndrome de Deleción 22q11/genética , Adolescente , Niño , Femenino , Humanos , Discapacidades para el Aprendizaje/psicología , Reino UnidoRESUMEN
Auditory hallucinations in schizophrenia are alleviated by antipsychotic agents that inhibit D2 dopamine receptors (Drd2s). The defective neural circuits and mechanisms of their sensitivity to antipsychotics are unknown. We identified a specific disruption of synaptic transmission at thalamocortical glutamatergic projections in the auditory cortex in murine models of schizophrenia-associated 22q11 deletion syndrome (22q11DS). This deficit is caused by an aberrant elevation of Drd2 in the thalamus, which renders 22q11DS thalamocortical projections sensitive to antipsychotics and causes a deficient acoustic startle response similar to that observed in schizophrenic patients. Haploinsufficiency of the microRNA-processing gene Dgcr8 is responsible for the Drd2 elevation and hypersensitivity of auditory thalamocortical projections to antipsychotics. This suggests that Dgcr8-microRNA-Drd2-dependent thalamocortical disruption is a pathogenic event underlying schizophrenia-associated psychosis.
Asunto(s)
Síndrome de Deleción 22q11/genética , Corteza Auditiva/metabolismo , Haploinsuficiencia , Proteínas de Unión al ARN/genética , Receptores de Dopamina D2/biosíntesis , Esquizofrenia/genética , Tálamo/metabolismo , Síndrome de Deleción 22q11/tratamiento farmacológico , Animales , Antipsicóticos/uso terapéutico , Modelos Animales de Enfermedad , Resistencia a Medicamentos/genética , Ratones , Ratones Mutantes , MicroARNs/metabolismo , Receptores de Dopamina D2/genética , Esquizofrenia/tratamiento farmacológico , Transmisión Sináptica/genéticaRESUMEN
22q11 deletion syndrome (22q11DS) is a genetic disorder caused by a microdeletion on chromosome 22, which includes the gene coding for catechol-O-methyl-transferase (COMT). High dopamine (DA) levels due to COMT haplo-insufficiency may be associated with the increased risk of developing schizophrenia in adults with 22q11DS. Reduced prepulse inhibition (PPI) of the acoustic startle response has been associated with schizophrenia and with disrupted DAergic transmission in the prefrontal cortex (PFC). COMT Val(158)Met polymorphism has been shown to influence PPI. We report the first study in adults with 22q11DS to examine PPI of the acoustic startle response and its modulation by COMT Val(158)Met polymorphism. Startle reactivity (SR) and PPI of the acoustic startle response were measured in 23 adults with 22q11DS and 21 healthy controls. 22q11DS subjects were genotyped for the functional COMT Val(158)Met polymorphism. 22q11DS Met hemizygotes showed reduced SR and PPI compared with 22q11DS Val hemizygotes. The effect of COMT Val(158)Met polymorphism on PPI was no longer significant when controlling for baseline SR. Met hemizygosity in 22q11DS is associated with reduced SR and influences PPI indirectly. Decreased PFC functioning following excessive PFC DA levels may be one of the mechanisms by which the Met genotype in 22q11DS disrupts SR.