The neuroanatomical substrates of autism and ADHD and their link to putative genomic underpinnings.

BACKGROUND: Autism spectrum disorders (ASD) are neurodevelopmental conditions accompanied by differences in brain development. Neuroanatomical differences in autism are variable across individuals and likely underpin distinct clinical phenotypes. To parse heterogeneity, it is essential to establish how the neurobiology of ASD is modulated by differences associated with co-occurring conditions, such as attention-deficit/hyperactivity disorder (ADHD). This study aimed to (1) investigate between-group differences in autistic individuals with and without co-occurring ADHD, and to (2) link these variances to putative genomic underpinnings. METHODS: We examined differences in cortical thickness (CT) and surface area (SA) and their genomic associations in a sample of 533 individuals from the Longitudinal European Autism Project. Using a general linear model including main effects of autism and ADHD, and an ASD-by-ADHD interaction, we examined to which degree ADHD modulates the autism-related neuroanatomy. Further, leveraging the spatial gene expression data of the Allen Human Brain Atlas, we identified genes whose spatial expression patterns resemble our neuroimaging findings. RESULTS: In addition to significant main effects for ASD and ADHD in fronto-temporal, limbic, and occipital regions, we observed a significant ASD-by-ADHD interaction in the left precentral gyrus and the right frontal gyrus for measures of CT and SA, respectively. Moreover, individuals with ASD + ADHD differed in CT to those without. Both main effects and the interaction were enriched for ASD-but not for ADHD-related genes. LIMITATIONS: Although we employed a multicenter design to overcome single-site recruitment limitations, our sample size of N = 25 individuals in the ADHD only group is relatively small compared to the other subgroups, which limits the generalizability of the results. Also, we assigned subjects into ADHD positive groupings according to the DSM-5 rating scale. While this is sufficient for obtaining a research diagnosis of ADHD, our approach did not take into account for how long the symptoms have been present, which is typically considered when assessing ADHD in the clinical setting. CONCLUSION: Thus, our findings suggest that the neuroanatomy of ASD is significantly modulated by ADHD, and that autistic individuals with co-occurring ADHD may have specific neuroanatomical underpinnings potentially mediated by atypical gene expression.

Interindividual Differences in Cortical Thickness and Their Genomic Underpinnings in Autism Spectrum Disorder.

OBJECTIVE: Autism spectrum disorder (ASD) is accompanied by highly individualized neuroanatomical deviations that potentially map onto distinct genotypes and clinical phenotypes. This study aimed to link differences in brain anatomy to specific biological pathways to pave the way toward targeted therapeutic interventions. METHODS: The authors examined neurodevelopmental differences in cortical thickness and their genomic underpinnings in a large and clinically diverse sample of 360 individuals with ASD and 279 typically developing control subjects (ages 6-30 years) within the EU-AIMS Longitudinal European Autism Project (LEAP). The authors also examined neurodevelopmental differences and their potential pathophysiological mechanisms between clinical ASD subgroups that differed in the severity and pattern of sensory features. RESULTS: In addition to significant between-group differences in "core" ASD brain regions (i.e., fronto-temporal and cingulate regions), individuals with ASD manifested as neuroanatomical outliers within the neurotypical cortical thickness range in a wider neural system, which was enriched for genes known to be implicated in ASD on the genetic and/or transcriptomic level. Within these regions, the individuals' total (i.e., accumulated) degree of neuroanatomical atypicality was significantly correlated with higher polygenic scores for ASD and other psychiatric conditions, and it scaled with measures of symptom severity. Differences in cortical thickness deviations were also associated with distinct sensory subgroups, especially in brain regions expressing genes involved in excitatory rather than inhibitory neurotransmission. CONCLUSIONS: The study findings corroborate the link between macroscopic differences in brain anatomy and the molecular mechanisms underpinning heterogeneity in ASD, and provide future targets for stratification and subtyping.

Clinics, prognosis and new therapeutic options in patients with mucosal melanoma: A retrospective analysis of 75 patients.

Mucosal melanomas represent a rare entity with different risk factors and molecular features compared to cutaneous melanomas. They arise most commonly from mucosal surfaces in the head/neck region, the female genital tract (FGT) and the anorectal region. The aim of this study was to evaluate clinics, prognosis, and treatment options of patients with mucosal melanoma, in particular with regard to different primary sites.We retrospectively analyzed 75 patients with mucosal melanomas diagnosed in the years 1993 to 2015 in our department. The primary melanomas were located in the head/neck region (n = 32), the FGT (n = 24), and the anorectal region (n = 19).The median age of the patients was 66 years. At initial diagnosis the primary melanoma was not completely resectable in 11 (15%) patients, 18 (24%) patients had regional lymph node metastases, and 7 (9%) patients distant metastases. During follow-up, 22 (29%) patients suffered from a local recurrence, in particular patients with primary melanoma in the head/neck region without postoperative radiotherapy. By multivariate analysis location of the primary melanoma in the head/neck area or anorectal region and presence of metastases at time of diagnosis represented poor prognostic factors for recurrence-free survival. In 62 tested individuals 7 KIT mutations were found, 2 BRAF mutations in 57 tested patients. Four patients received targeted therapies, 14 checkpoint inhibitors, 4 (1/1 on vemurafenib, 1/7 on ipilimumab, and 2/7 on PD-1 inhibitors) patients showed responses of more than 100 days duration.Mucosal melanomas are often locally advanced or metastatic at initial diagnosis, thus they require extensive staging procedures. The high rate of local recurrences in the head/neck region can be significantly reduced by postoperative radiotherapy. For the potential use of medical treatment a mutation analysis for KIT and BRAF genes should be performed. The use of new immunologic and targeted therapies has to be further evaluated.