Uncovering the Genetic and Molecular Features of Huntington's Disease in Northern Colombia.

Huntington's disease (HD) is a genetic disorder caused by a CAG trinucleotide expansion in the huntingtin (HTT) gene. Juan de Acosta, Atlántico, a city located on the Caribbean coast of Colombia, is home to the world's second-largest HD pedigree. Here, we include 291 descendants of this pedigree with at least one family member with HD. Blood samples were collected, and genomic DNA was extracted. We quantified the HTT CAG expansion using an amplicon sequencing protocol. The genetic heterogeneity was measured as the ratio of the mosaicism allele's read peak and the slippage ratio of the allele's read peak from our sequence data. The statistical and bioinformatic analyses were performed with a significance threshold of p < 0.05. We found that the average HTT CAG repeat length in all participants was 21.91 (SD = 8.92). Of the 291 participants, 33 (11.3%, 18 females) had a positive molecular diagnosis for HD. Most affected individuals were adults, and the most common primary and secondary alleles were 17/7 (CAG/CCG) and 17/10 (CAG/CCG), respectively. The mosaicism increased with age in the participants with HD, while the slippage analyses revealed differences by the HD allele type only for the secondary allele. The slippage tended to increase with the HTT CAG repeat length in the participants with HD, but the increase was not statistically significant. This study analyzed the genetic and molecular features of 291 participants, including 33 with HD. We found that the mosaicism increased with age in the participants with HD, particularly for the secondary allele. The most common haplotype was 17/7_17/10. The slippage for the secondary allele varied by the HD allele type, but there was no significant difference in the slippage by sex. Our findings offer valuable insights into HD and could have implications for future research and clinical management.

Two sides of the same coin: ADHD affects reactive but not proactive inhibition in children.

Children with attention-deficit/hyperactivity disorder (ADHD) present a deficit in inhibitory control. Still, it remains unclear whether it comes from a deficit in reactive inhibition (ability to stop the action in progress), proactive inhibition (ability to exert preparatory control), or both.We compared the performance of 39 children with ADHD and 42 typically developing children performing a Simon choice reaction time task. The Simon task is a conflict task that is well-adapted to dissociate proactive and reactive inhibition. Beyond classical global measures (mean reaction time, accuracy rate, and interference effect), we used more sophisticated dynamic analyses of the interference effect and accuracy rate to investigate reactive inhibition. We studied proactive inhibition through the congruency sequence effect (CSE).Our results showed that children with ADHD had impaired reactive but not proactive inhibition. Moreover, the deficit found in reactive inhibition seems to be due to both a stronger impulse capture and more difficulties in inhibiting impulsive responses. These findings contribute to a better understanding of how ADHD affects inhibitory control in children.

Executive Function and Theory of Mind in Children with ADHD: a Systematic Review.

In developmental research, the relationship between Executive Function (EF) and Theory of Mind (ToM) has been extensively assessed, and EF has been considered a condition for ToM. However, few researchers have studied the relationship between EF and ToM in clinical populations, especially that of Attention Deficit Hyperactivity Disorder (ADHD), a neurodevelopmental disorder characterized by symptoms of inattention and motor hyperactivity/impulsivity, in which EF is largely impaired. Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) model, 201 English and Spanish articles evaluating EF and ToM in ADHD were chosen. Fifteen papers met the inclusion criteria and were selected for further analysis. The first study dates from 2001. Most of the studies' designs are cross-sectional, include mostly male children, have a small sample size, and were conducted in European countries. Unlike tasks assessing EF, tasks assessing ToM were heterogeneous across studies. The EFs most correlated with ToM were inhibitory control, working memory, cognitive flexibility, and attention. Interest in studying the relationship between EF and ToM in ADHD is recent,but increasing based on new findings and tuning of ToM instruments. However, while an association between EF and ToM is indicated in ADHD, the degree of prediction and predictability of one over the other cannot yet be established because of the studies' heterogeneity.

Theory of Mind in Huntington's Disease: A Systematic Review of 20 Years of Research.

Background: People with Huntington's disease (HD) exhibit neurocognitive alterations throughout the disease, including deficits in social cognitive processes such as Theory of Mind (ToM). Objective: The aim is to identify methodologies and ToM instruments employed in HD, alongside relevant findings, within the scientific literature of the past two decades. Methods: We conducted a comprehensive search for relevant papers in the SCOPUS, PubMed, APA-PsyArticles, Web of Science, Redalyc, and SciELO databases. In the selection process, we specifically focused on studies that included individuals with a confirmed genetic status of HD and investigated ToM functioning in patients with and without motor symptoms. The systematic review followed the PRISMA protocol. Results: A total of 27 papers were selected for this systematic review, covering the period from 2003 to 2023. The findings consistently indicate that ToM is globally affected in patients with manifest motor symptoms. In individuals without motor symptoms, impairments are focused on the affective dimensions of ToM. Conclusions: Based on our analysis, affective ToM could be considered a potential biomarker for HD. Therefore, it is recommended that ToM assessment be included as part of neuropsychological evaluation protocols in clinical settings. Suchinclusion could aid in the identification of early stages of the disease and provide new opportunities for treatment, particularly with emerging drugs like antisense oligomers. The Prospero registration number for this review is CRD42020209769.

ADGRL3, FGF1 and DRD4: Linkage and Association with Working Memory and Perceptual Organization Candidate Endophenotypes in ADHD.

Attention deficit hyperactivity disorder (ADHD) is a highly heritable neurobehavioral disorder that affects children worldwide, with detrimental long-term consequences in affected individuals. ADHD-affected patients display visual-motor and visuospatial abilities and skills that depart from those exhibited by non-affected individuals and struggle with perceptual organization, which might partially explain impulsive responses. Endophenotypes (quantifiable or dimensional constructs that are closely related to the root cause of the disease) might provide a more powerful and objective framework for dissecting the underlying neurobiology of ADHD than that of categories offered by the syndromic classification. In here, we explore the potential presence of the linkage and association of single-nucleotide polymorphisms (SNPs), harbored in genes implicated in the etiology of ADHD (ADGRL3, DRD4, and FGF1), with cognitive endophenotypes related to working memory and perceptual organization in 113 nuclear families. These families were ascertained from a geographical area of the Caribbean coast, in the north of Colombia, where the community is characterized by its ethnic diversity and differential gene pool. We found a significant association and linkage of markers ADGRL3-rs1565902, DRD4-rs916457 and FGF1-rs2282794 to neuropsychological tasks outlining working memory and perceptual organization such as performance in the digits forward and backward, arithmetic, similarities, the completion of figures and the assembly of objects. Our results provide strong support to understand ADHD as a combination of working memory and perceptual organization deficits and highlight the importance of the genetic background shaping the neurobiology, clinical complexity, and physiopathology of ADHD. Further, this study supplements new information regarding an ethnically diverse community with a vast African American contribution, where ADHD studies are scarce.

Impulsive and Omission Errors: Potential Temporal Processing Endophenotypes in ADHD.

Temporal processing (TP) is associated with functions such as perception, verbal skills, temporal perspective, and future planning, and is intercorrelated with working memory, attention, and inhibitory control, which are highly impaired in individuals with attention deficit hyperactivity disorder (ADHD). Here we evaluate TP measures as potential endophenotypes in Caribbean families ascertained from probands affected by ADHD. A total of 232 individuals were recruited and clinically evaluated using an extensive battery of neuropsychological tasks and reaction time (RT)-based task paradigms. Further, the heritability (genetic variance underpinning phenotype) was estimated as a measure of the genetics apportionment. A predictive framework for ADHD diagnosis was derived using these tasks. We found that individuals with ADHD differed from controls in neuropsychological tasks assessing mental control, visual-verbal memory, verbal fluency, verbal, and semantic fluency. In addition, TP measures such as RT, errors, and variability were also affected in individuals with ADHD. Moreover, we determined that only omission and commission errors had significant heritability. In conclusion, we have disentangled omission and commission errors as possible TP endophenotypes in ADHD, which can be suitable to assess the neurobiological and genetic basis of ADHD. A predictive model using these endophenotypes led to remarkable sensitivity, specificity, precision and classification rate for ADHD diagnosis, and may be a useful tool for patients' diagnosis, follow-up, and longitudinal assessment in the clinical setting.

Prepotent response inhibition and reaction times in children with attention deficit/hyperactivity disorder from a Caribbean community.

Impairment in inhibitory control has been postulated as an underlying hallmark of attention deficit/hyperactivity disorder (ADHD), which can be utilized as a quantitative trait for genetic studies. Here, we evaluate whether inhibitory control, measured by simple automatized prepotent response (PR) inhibition variables, is a robust discriminant function for the diagnosis of ADHD in children and can be used as an endophenotype for future genetic studies. One hundred fifty-two school children (30.9% female, 67.8% with ADHD) were recruited. The ADHD checklist was used as the screening tool, whilst the DSM-IV Mini International Neuropsychiatry Interview, neurologic interview and neurologic examination, and the WISC III FSIQ test were administered as the gold standard procedure to assert ADHD diagnosis. A Go/No-Go task using a naturalistic and automatized visual signal was administered. A linear multifactor model (MANOVA) was fitted to compare groups including ADHD status, age, and gender as multiple independent factors. Linear discriminant analysis and the receiver operating characteristic curve were used to assess the predictive performance of PR inhibition variables for ADHD diagnosis. We found that four variables of prepotent response reaction time- and prepotent response inhibition established statistically significant differences between children with and without ADHD. Furthermore, these variables generated a strong discriminant function with a total classification capability of 73, 84% specificity, 68% sensitivity, and 90% positive predictive value for ADHD diagnosis, which support reaction times as a candidate endophenotype that could potentially be used in future ADHD genetic research.

Adaptación al español de cuatro instrumentos para evaluar la teoría de la mente en niños y adolescentes / Spanish adaptation of four instruments to asses Theory of Mind in Children and adolescents

Resumen Introducción: La teoría de la mente (ToM) es una de las dimensiones de la Cognición Social más relevantes y de gran interés para la investigación en psicología del desarrollo, psicología cognitiva, neuropsicología y neurociencias sociales, así como en la labor clínica. Esto ha conllevado a la generación de instrumentos validados para la evaluación de esta función; sin embargo, en español son pocos los que hay y aún menos los adaptados para población infantil y adolescente. Objetivo: En el presente trabajo se presenta la adaptación de la Batería de la ToM, el inventario de la ToM, el Test de Paso en Falso y el Test de la Mirada, cuatro instrumentos con tareas clásicas para evaluar la ToM. Método: El proceso de adaptación se hizo en dos fases, una de traducción al español y otra de adaptación cultural. Para verificar los resultados se hizo un pilotaje para todos los instrumentos con 20 participantes en edades entre 4 y 13 años y 20 participantes entre 6 y 17 años. Resultados: Se presentan los cuatro instrumentos adaptados en español con los principales ajustes en cada uno de ellos. Discusión: Se discute sobre la importancia de generar un protocolo de valoración de la ToM haciendo una validación estadística de estos instrumentos.

Abstract Introduction: Theory of Mind (ToM) is one of the most important dimensions of Social Cognition (SC); it is of great interest for research in Development Psychology, Cognitive Psychology, Neuropsychology, and Social Neuroscience as well as for clinical practice. It has stimulated the creation and validation of instruments to asses this dimension as a cognitive process, but there are few instruments like these in Spanish and less to evaluating children and adolescents. Objective: This paper reports the adaptation into Spanish of four instruments to asses ToM: The Theory of Mind Battery, The Theory of Mind Inventory-2, the Reading the Mind in the Eyes and the Faux Pas Test. Method: The adaptation process was made in two steps first, translation and, second, cultural adaptation. To verify the results a pilot testing was carried out in two groups, one with children between 4 and 13 years old and other with children and adolescents between 6 and 17 years old. Results: Instruments adapted into Spanish are presented as results highlighting the main adjustments made to each tool. Discussion: The importance of creating a protocol with statistical validation to asses ToM are discussed.

Influencia del riesgo social en la teoría de la mente y funciones ejecutivas de adolescentes colombianos / Influence of Social Risk in the Theory of Mind and Executive Functions of Colombian Teenagers

Resumen El objetivo del presente estudio fue determinar la influencia del riesgo social en el rendimiento, en tareas de Funciones Ejecutivas (FE) y Teoría de la Mente (ToM) en adolescentes colombianos. Participaron 78 adolescentes (41 en riesgo social y 37 controles) entre los 13 y 16 años de edad seleccionados a través de un muestreo intencional. Se administró el Test de Palabras y Colores de Stroop, el Test de la Pirámide de México y el Test de Falso Paso para evaluar control inhibitorio, planificación y ToM, respectivamente. A pesar de que no se encontraron diferencias significativas en las FE de control inhibitorio y planificación, se encontraron diferencias en el desempeño en algunas dimensiones de la prueba de ToM. Adicionalmente, mientras que al interior del grupo sin riesgo social se observó una relación entre la ToM y las FE evaluadas, al interior del grupo en riesgo social estos procesos no estuvieron relacionados. Se concluye que un entorno de riesgo social parece no afectar las FE de control inhibitorio y planificación o la habilidad para detectar comportamientos inapropiados, pero sí la habilidad para realizar inferencias acerca de los estados mentales de los otros. Asimismo, un entorno de riesgo social es un factor ambiental que parece disociar el proceso de desarrollo de la cognición social y de los procesos ejecutivos en adolescentes, desarrollo que debería darse de manera paralela.

Abstract The objective of the present study was to determine the influence of social risk in the performance of Colombian adolescents in ToM and EF tasks. The participants were 78 adolescents (41 in social risk and 37 controls) between 13 and 16 years of age. The Stroop Test, the Pyramid of Mexico subtest and the Faux Pas Recognition Test where used to assess inhibitory Control, Planning and ToM in the participants, respectively. Although no significant differences were found in the executive functions of Inhibiting Control and Planning, some differences were found in the performance of the ToM test. Additionally, whereas in the control group a relationship between ToM and executive functions was observed, in the at social risk group these processes were not related. These findings reveal that being at social risk does not affect the Executive Functions of Control and Planning but it does have an effect in the ability to make inferences about the mental states of others. Moreover, being at social risk can be an environmental factor that can dissociate the development process of social cognition and executive functions, which are supposed to occur parallelly.

Conglomerados de clases latentes en 408 miembros de 120 familias nucleares de Barranquilla con un caso índice afectado de trastorno de atención hiperactividad (TDAH) / Latent class clusters in 408 members of 120 nuclear families from Barranquilla with a proband attention deficit hyperactivity disorder (adhd) affected case

Resumen Introducción: el análisis de conglomerados de clases latentes (ACCL) es un procedimiento estadístico para agrupamientos, dependiendo de la respuesta a cada ítem. Se ha usado con el trastorno de atención hiperactividad (TDAH), para derivar tipos sutiles de casos en estudios genéticos. Objetivo: analizar los CCL de 408 miembros de 120 familias con un caso índice de TDAH, en relación con los síntomas registrados en la entrevista psiquiátrica. Pacientes y métodos: a partir de un caso índice (niño escolarizado de Barranquilla con diagnóstico estándar de oro de TDAH) se construyeron familias nucleares, las cuales de evaluaron para el diagnóstico de TDAH y comorbilidades. La muestra fue de 408 miembros de 120 familias, edad 26,6 ± 15,4 años. Con el programa para computador Latent-Gold 4,0 se hizo el ACCL con la respuesta nominal para cada síntoma de TDAH, y la presencia o no de comorbilidades con TOD y TDC. Se usó el sexo y la edad como covariables categóricas. Se hizo un análisis cruzado de cada conglomerado con el diagnóstico estándar de oro. Resultados: el mejor modelo (índices de verosimilitud) fue de 6 CCL (p Bootstrap = 0,08). El conglomerado 1 (32,5 %) son adultos, predominio de sexo femenino, probabilidad < 20 % de síntomas y comorbilidades. El segundo (17,4 %) son adultos y niños de sexo masculino con 40 a 80 % de síntomas de TDAH combinado. El grupo tres (15,7 %) son niños con ~100 % síntomas de TDAH combinado, TOD y TDC. El cuarto conglomerado (14,3 %) son adultos de ambos sexos con 20 a 50 % probabilidades de hiperactividad-impulsividad, TOD (70 %) y TDC (40 %). El grupo 5 (10,6 %) en un 80 % adultos con 30 a 90 % probabilidades de inatención sin comorbilidades. El conglomerado 6 (9,5 %) con altas probabilidades de síntomas de inatención. Conclusiones: se derivaron 6 CCL. Cuatro conglomerados son de afectados, 1 de no afectados y 1 con similar proporción de afectados y no afectados, los cuales podrían ser usados en análisis con marcadores genéticos de susceptibilidad para TDAH.

Summary Introduction: Latent class cluster analysis (LCCA) is a statistical procedure to sort a sample, according to item response of each member of a sample. It has been used with ADHD in order to derive mild cases for genetic studies. Objective: To analyze LCC from 408 members of 120 nuclear families with a ADHD proband, related to registered symptoms obtained with a structured psychiatric interview. Patient and methods: From a proband (school -gold standard- ADHD affected child from Barranquilla) nuclear families were recruited, which were assess for ADHD and comorbidities diagnoses. Sample was 408 members of 120 nuclear families, mean age 26,6 ± 15,4 years old. Using Latent Gold 4,0 software, an ACCL with each ADHD categorical symptoms, and comorbidities with ODD and CD was run. Gender and age were used as categorical active covariables. A cross tabulation analysis between LCC and ADHD gold standard diagnosis was done. Results: The best model (maximum likelihood index) was a 6 LCC (p Bootstrap = 0,08). Cluster 1 (32,5%) were predominantly female adults with low (< 20%) probability of ADHD symptoms. Cluster 2 (17,4%) were adults and children with 40 to 80% probabilities of combined ADHD symptoms. Cluster 3 (15,7%) were children with ~100% of ADHD combined symptoms with ODD and CD comorbidities. Cluster 4 (14,3%) were adults of both genders with 20 to 50% probabilities of hyperactivity - impulsivity and ODD (70%) and CD (40%). Cluster 5 (10,6%) were 80% adults with 30 to 90% probabilities of inattentive symptoms without comorbidities. Cluster 6 (9,5%) had high probabilities of inattentive symptoms. Conclusions: A 6 LCC model was obtained. Four LCC were ADHD affected, one was unaffected and one with similar proportion of affected and unaffected members, which would are able to be used for genetic analyses with ADHD susceptibility gene markers.

Déficit en habilidades sociales en niños con Trastorno por Déficit de Atención-Hiperactividad, evaluados con la Escala BASC / Déficit em habilidades sociais em crianças com Transtorno por Déficit de Atenção-Hiperatividade, avaliados com a escala BASC / Social skills deficits in children diagnosed with Attention Deficit Hyperactivity Disorder evaluated with the BASC scale

Se analizaron las Habilidades Sociales (HS) de 159 niños de ambos sexos, escolarizados, con Trastorno por Déficit de Atención-Hiperactividad (TDAH), entre los 6 y los 11 años de edad. La valoración de las HS se realizó con la escala Behavioral Assessment System for Children para padres y maestros. Los resultados mostraron que los niños con TDAH presentan puntajes más bajos en las dimensiones de habilidades sociales como escuchar, esperar turnos, reconocer señales sociales y tener capacidad de adaptabilidad. Sin embargo, en compañerismo, los participantes con TDAH combinado poseen habilidades semejantes a los no afectados. Esto replantea lo encontrado en la mayoría de los estudios en donde únicamente se evidencian deficiencias...

The study analyzed the Social Skills (SS) of 159 male and female school children between the ages of 6 and 11, suffering from Attention Deficit Hyperactivity Disorder (ADHD). The evaluation of SS was carried out with the Behavioral Assessment System for Children for use by parents and teachers. The results showed that children with ADHD feature lower scores in social skills such as listening, respecting turns, recognizing social signals, and adaptability. However, participants with ADHD proved to have companionship skills similar to those of unaffected children. This makes it necessary to rethink the findings of the majority of studies, which only reveal deficiencies...

Analisaram-se as Habilidades Sociais (HS) de 159 crianças, escolarizadas, com Transtorno por Déficit de Atenção-Hiperatividade (TDAH), entre 6 e 11 anos de idade. A valoração das HS se realizou com a escala Behavioral Assessment System for Children para pais e mestres. Os resultados mostraram que as crianças com TDAH apresentam pontuações mais baixas nas dimensões de HS como escutar, esperar a vez, reconhecer sinais sociais e ter capacidade de adaptabilidade. Contudo, em companheirismo, os participantes com TDAH combinado possuem habilidades semelhantes aos não afetados. Isso repropõe o encontrado na maioria dos estudos nos quais unicamente se evidenciam deficiências...