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Autism spectrum disorder (ASD) has a complex genetic architecture involving contributions from both de novo and inherited variation. Few studies have been designed to address the role of rare inherited variation or its interaction with common polygenic risk in ASD. Here, we performed whole-genome sequencing of the largest cohort of multiplex families to date, consisting of 4,551 individuals in 1,004 families having two or more autistic children. Using this study design, we identify seven previously unrecognized ASD risk genes supported by a majority of rare inherited variants, finding support for a total of 74 genes in our cohort and a total of 152 genes after combined analysis with other studies. Autistic children from multiplex families demonstrate an increased burden of rare inherited protein-truncating variants in known ASD risk genes. We also find that ASD polygenic score (PGS) is overtransmitted from nonautistic parents to autistic children who also harbor rare inherited variants, consistent with combinatorial effects in the offspring, which may explain the reduced penetrance of these rare variants in parents. We also observe that in addition to social dysfunction, language delay is associated with ASD PGS overtransmission. These results are consistent with an additive complex genetic risk architecture of ASD involving rare and common variation and further suggest that language delay is a core biological feature of ASD. [ABSTRACT FROM AUTHOR]

Objective: Adverse childhood experiences are linked to the development of a number of psychiatric illnesses in adulthood. Our study examined the pattern of adverse childhood experiences and their relation to the age of onset of major psychiatric conditions in individuals from families that had ⩾2 first-degree relatives with major psychiatric conditions (multiplex families), identified as part of an ongoing longitudinal study. Methods: Our sample consisted of 509 individuals from 215 families. Of these, 268 were affected, i.e., diagnosed with bipolar disorder (n = 61), obsessive–compulsive disorder (n = 58), schizophrenia (n = 52), substance dependence (n = 59) or co-occurring diagnoses (n = 38), while 241 were at-risk first-degree relatives who were either unaffected (n = 210) or had other depressive or anxiety disorders (n = 31). All individuals were evaluated using the Adverse Childhood Experiences – International Questionnaire and total adverse childhood experiences exposure and severity scores were calculated. Results: It was seen that affected males, as a group, had the greatest adverse childhood experiences exposure and severity scores in our sample. A Cox mixed effects model fit by gender revealed that a higher total adverse childhood experiences severity score was associated with significantly increased risk for an earlier age of onset of psychiatric diagnoses in males. A similar model that evaluated the interaction of diagnosis revealed an earlier age of onset in obsessive–compulsive disorder and substance dependence, but not in schizophrenia and bipolar disorder. Conclusion: Our study indicates that adverse childhood experiences were associated with an earlier onset of major psychiatric conditions in men and individuals diagnosed with obsessive–compulsive disorder and substance dependence. Ongoing longitudinal assessments in first-degree relatives from these families are expected to identify mechanisms underlying this relationship. [ABSTRACT FROM AUTHOR]

ADHD often affects multiple generations in a family. Previous studies suggested that children with ADHD benefit less from therapy if parents are also affected, since ADHD symptoms interfere with treatment implementation. This two-group randomised controlled trial examined whether targeting maternal ADHD boosts the efficacy of parent–child training (PCT) for the child's ADHD. Here, we report follow-up results 2 years from baseline. Mothers of 144 mother–child dyads (ADHD according to DSM-IV) were examined for eligibility (T1) and randomised to 12 weeks of intensive multimodal treatment comprising pharmacotherapy and DBT-based cognitive behavioural group psychotherapy (TG, n = 77) or clinical management comprising non-specific counselling (CG, n = 67) for Step 1 (concluded by T2). Subsequently, all dyads participated in 12 weekly PCT sessions for Step 2 (concluded by T3). In Step 3, participants received maintenance treatments for 6 months (concluded by T4). At 24 months after baseline (T5), we performed follow-up assessments. The primary endpoint was child ADHD/ODD score (observer blind rating). Outcomes at T5 were evaluated using ANCOVA. Assessments from 101 children and 95 mothers were available at T5. Adjusted means (m) of ADHD/ODD symptoms (range 0–26) in children did not differ between TG and CG (mean difference = 1.0; 95% CI 1.2–3.1). The maternal advantage of TG over CG on the CAARS-O:L ADHD index (range 0–36) disappeared at T5 (mean difference = 0.2; 95% CI − 2.3 to 2.6). Sensitivity analyses controlling for medication and significant predictors of follow-up participation showed unchanged outcomes. Within-group outcomes remained improved from baseline. At the 24-month follow-up, TG and CG converged. The superiority of intensive treatment regarding maternal symptoms disappeared. In general, cross-generational treatment seems to be effective in the long term. (BMBF grant 01GV0605; registration ISRCTN73911400). [ABSTRACT FROM AUTHOR]

Patient awareness of medical conditions may influence treatment seeking and monitoring of these conditions. Accurate awareness of hypertension reported to clinicians evaluating patients for whom clinical history is limited, such as in emergency care, can aid in diagnosis by revealing whether measured hypertension is typical or atypical. Measurement of blood pressure in a laboratory study was assessed at rest, immediately before phlebotomy, and within 10 minutes after. The resting measure was used to determine the accuracy of self-reported hypertension in 283 adults. Parametric analyses were conducted to identify potential variables influencing accuracy of self-reported hypertension. Sensitivity, specificity, and the kappa coefficient of agreement were calculated to determine the influence of alcohol dependence (AD), sex, age, and cigarette smoking on hypertension awareness. Self-report was mildly sensitive, correctly identifying individuals with hypertension in approximately 37% of the cases, but was highly specific (95%) in identifying individuals without hypertension. Similar sensitivities were found in analyses separated by sex. Sensitivity was greater in those over age 55 (53%) in comparison with those <54, as well as in those who were not smoking. Comparison of those with and without a history of AD revealed that both groups show similar accuracy in reporting hypertension. Absence of hypertension can be accurately determined with self-report data in those without hypertension. A significant proportion of those with measured hypertension report an absence of hypertension. [ABSTRACT FROM AUTHOR]

Much research has explored how raising a child with a neurodevelopmental disability influences parents' well-being. However, little research has focused on the unique experiences of parenting multiple children with neurodevelopmental disabilities. We explored the unique experiences of parenting multiple children with neurodevelopmental disabilities with a focus on mothers' well-being and social participation. Ten mothers who parent multiple children with neurodevelopmental disabilities participated in semi-structured interviews. Interviews were analyzed using a reflexive thematic approach. Three themes were identified: ' Knowledge is power ' described positive influences of enhanced disability knowledge and advocacy with each child who experienced disability. ' Shifts in wellbeing' acknowledged these mothers' exhaustion, decreased time for self-care, and invisible work, yet also increased feelings of empowerment, purpose and empathy for others. ' (Dis)Connection and engagement with others' reflected struggles of balancing responsibilities, social and community participation, and experiences with isolation. Yet, mothers' also experienced enhanced disability community and family connections, and a sense of meaning and purpose. Findings highlighted challenges, and many rewarding and unique experiences of parenting multiple children with neurodevelopmental disabilities. Health, education and social service practitioners are encouraged to acknowledge parent's challenges, but also celebrate and draw on families' strengths and knowledge. • Parenting multiple children with disabilities is unique to one child with disability • While often similar, challenges and benefits were exacerbated with multiple children • Unique positive outcomes were feeling knowledgeable and able to strongly advocate • They also found connection in the disability community, and strong sibling bonds [ABSTRACT FROM AUTHOR]

Objectives: Autoimmune diseases (AIDs) cluster in families; however, to what extent AIDs co‐occur in MS multiplex families with two or more affected individuals is still controversial. The study aimed to evaluate coexisting AIDs in this type of families from the Netherlands. Materials and methods: A total of 155 MS multiplex families (155 MS probands, 959 first‐degree relatives and 212 spouses) were characterized for a history of 11 AIDs by means of a self‐administered questionnaire. Results: In 43.2% of MS multiplex families, at least one AID was present in the first‐degree relatives. Overall, the frequency of AIDs was not significantly different between patients with MS (11%), their first‐degree family members (11%) and controls (5.2%). After correction for age at inclusion and gender, the odds ratios (OR) for AIDs were not significant for patients with MS (OR = 1.8 [0.77‐4.34], P = .17) and first‐degree family members (OR = 2.0 [0.98‐4.10], P = .06) when both compared to spouses. The frequency of AIDs in mothers did not differ from that in fathers after correction for sex bias (19% vs 8%, P = .51). A presence of AID was more often reported in maternal than paternal second‐degree relatives (23% vs 10%, P = .0020). Conclusion: Although nearly half of the Dutch MS multiplex families reported an AID, no excess of AIDs was present in patients with MS from multiplex families or their first‐degree family members compared to the spouses. [ABSTRACT FROM AUTHOR]

Sleep disorders often co-occur with autism spectrum disorder. They further exacerbate autism spectrum disorder symptoms and interfere with children's and parental quality of life. This study examines whether gastrointestinal dysfunctions increase the odds of having sleep disorders in 610 children with idiopathic autism spectrum disorder, aged 2-18 years, from the Autism Genetic Resource Exchange research program. The adjusted odds ratio for sleep disorder among those with gastrointestinal dysfunctions compared to those without was 1.74 (95% confidence interval: 1.22-2.48). In addition, the odds of having multiple sleep disorder symptoms among children with gastrointestinal dysfunctions, adjusted for age, gender, behavioral problems, bed wetting, current and past supplements, and current and past medications for autism spectrum disorder symptoms were 1.75 (95% confidence interval: 1.10-2.79) compared to children without gastrointestinal dysfunctions. Early detection and treatment of gastrointestinal dysfunctions in autism spectrum disorder may be means to reduce prevalence and severity of sleep problems and improve quality of life and developmental outcomes in this population. [ABSTRACT FROM AUTHOR]

Gene identification in epilepsy has mainly been limited to large families segregating genes of major effect and de novo mutations in epileptic encephalopathies. Many families that present with common non-acquired focal epilepsies and genetic generalized epilepsies remain unexplained. We assembled a cohort of 'genetically enriched' common epilepsies by collecting and phenotyping families containing multiple individuals with unprovoked seizures. We aimed to determine if specific clinical epilepsy features aggregate within families, and whether this segregation of phenotypes may constitute distinct 'familial syndromes' that could inform genomic analyses. Families with three or more individuals with unprovoked seizures were studied across multiple international centres. Affected individuals were phenotyped and classified according to specific electroclinical syndromes. Families were categorized based on syndromic groupings of affected family members, examined for pedigree structure and phenotypic patterns and, where possible, assigned specific familial epilepsy syndromes. A total of 303 families were assembled and analysed, comprising 1120 affected phenotyped individuals. Of the 303 families, 117 exclusively segregated generalized epilepsy, 62 focal epilepsy, and 22 were classified as genetic epilepsy with febrile seizures plus. Over one-third (102 families) were observed to have mixed epilepsy phenotypes: 78 had both generalized and focal epilepsy features within the same individual (n = 39), or within first or second degree relatives (n = 39). Among the genetic generalized epilepsy families, absence epilepsies were found to cluster within families independently of juvenile myoclonic epilepsy, and significantly more females were affected than males. Of the 62 familial focal epilepsy families, two previously undescribed familial focal syndrome patterns were evident: 15 families had posterior quadrant epilepsies, including seven with occipito-temporal localization and seven with temporo-parietal foci, and four families displayed familial focal epilepsy of childhood with multiple affected siblings that was suggestive of recessive inheritance. The findings suggest (i) specific patterns of syndromic familial aggregation occur, including newly recognized forms of familial focal epilepsy; (ii) although syndrome-specificity usually occurs in multiplex families, the one-third of families with features of both focal and generalized epilepsy is suggestive of shared genetic determinants; and (iii) patterns of features observed across families including pedigree structure, sex, and age of onset may hold clues for future gene identification. Such detailed phenotypic information will be invaluable in the conditioning and interpretation of forthcoming sequencing data to understand the genetic architecture and inter-relationships of the common epilepsy syndromes. [ABSTRACT FROM AUTHOR]

Objective To describe the physical, social, educational and employment status and clinical outcomes of patients with juvenile idiopathic arthritis ( JIA) from multiplex families. Methods All familial JIA patients were treated and had regular follow-up between 1990 and 2015 at King Faisal Specialist Hospital and Research Center ( KFSH- RC), Riyadh, were included. Demographic data, disease duration, active arthritis and articular and extra-articular damage at last follow-up visit were reviewed. Additionally, social, educational and employment history were obtained via personal or phone interviews. Results Twenty-three patients (20 females) belonging to 10 families were included. The mean age was 14.6 (±9) years with mean disease duration of 11.4 (±9) years and mean follow-up duration of 10.5 (±6). Fourteen patients had systemic JIA while eight patients had polyarticular subtype, and one patient had psoriatic arthritis. All patients received concomitant treatment. Twenty-one patients commenced biologic agents; treatment switched to another agent in all of them because of inadequate response. Most patients had progressive disease course. Twelve patients had active polyarthritis and 22 patients showed evidence of articular damage. All patients had raised inflammatory markers. Eighteen patients had short stature and 11 patients had delayed puberty. Two patients had lower limb lymphedema and one patient had a single kidney with refractory hypertension. Three patients underwent hip arthroplasty. Seventeen patients had satisfactory educational achievement and four patients were in employment. Two patients died due to infection. Conclusion Our results showed the largest familial clusters of JIA in the Middle East. Patients with familial JIA had refractory disease with progressive disease course. [ABSTRACT FROM AUTHOR]

Single nucleotide polymorphisms (SNPs)-based genotyping using microarray platform is now frequently used to detect copy number variants (CNVs) in the human genome. Here, we report CNVs identified using Illumina Human Omni 2.5 M oligonucleotide microarrays in 11 multiplex families with autism spectrum disorder (ASD) referred to Autism Research and Treatment Center (ART) and Madinah Maternity and Children Hospital (MMCH). Of the 11 families, 22 patients with ASD (all males) and their parents, were recruited for the present study. In total, 43 individuals were genotyped with high-resolution array. Abnormal microarray results were seen in all 22 patients with ASD. A total of 17 shared CNVs were selected for further analysis. Out of these 17 CNVs, we discovered one novel CNV, previously not described, and 16 recurrent CNVs that overlap with the genomic imbalances defined in the autism database, autism chromosome rearrangement database and database of genomic variants. Recurrent CNVs include 11 common and 5 rare CNVs. All rare CNVs are duplications except a 16-kb deletion on chr2q36.3. Rare gain of copy numbers includes a 2-kb duplication on chr9q21.13, overlapping duplications of 107 kb and 181 kb on chrXp22.33 in 2 different families and a 10-kb duplication on chr18q21.13. A novel loss of copy number on chr3q23 was found in four ASD cases. This CNV results in deletion of intron 2 of calsyntenin 2 ( CLSTN2 ) encoding synaptic protein calsyntenin 2. CLSTN2 is expressed exclusively in the brain, with high levels occurring in cortical gamma-aminobutyric acid (GABA)ergic interneurons and in medial temporal lobe regions. These results verify the diagnostic relevance of genome-wide small common and rare CNVs and provide further evidence of the high diagnostic yield of microarray for genetic testing in children with ASD. [ABSTRACT FROM AUTHOR]

Background: Autism spectrum disorders (ASDs) are more prevalent in males, suggesting a multiple threshold liability model in which females are, on average, protected by sex-differential mechanisms. Under this model, autistic females are predicted to carry a more penetrant risk variant load than males and to share this greater genetic liability with their siblings. However, reported ASD recurrence rates have not demonstrated significantly increased risk to siblings of affected girls. Here, we characterize recurrence patterns in multiplex families from the Autism Genetics Resource Exchange (AGRE) to determine if risk in these families follows a female protective model. Methods: We assess recurrence rates and quantitative traits in full siblings from 1,120 multiplex nuclear families and concordance rates in 305 twin pairs from AGRE. We consider the first two affected children per family, and one randomly selected autistic twin per pair, as probands. We then compare recurrence rates and phenotypes between males and females and between twin pairs or families with at least one female proband (female-containing (FC)) versus those with only male probands (male-only (MO)). Results: Among children born after two probands, we observe significantly higher recurrence in males (47.5%) than in females (21.1%; relative risk, RR = 2.25; adjusted P = 6.22e-08) and in siblings of female (44.3%) versus siblings of male probands (30.4%; RR = 1.46; adj. P = 0.036). This sex-differential recurrence is also robust in dizygotic twin pairs (males = 61.5%, females = 19.1%; RR = 3.23; adj. P = 7.66e-09). Additionally, we find a significant negative relationship between interbirth interval and ASD recurrence that is driven by children in MO families. Conclusions: By classifying families as MO or FC using two probands instead of one, we observe significant recurrence rate differences between families harboring sex-differential familial liability. However, a significant sex difference in risk to children within FC families suggests that female protective mechanisms are still operative in families carrying high genetic risk loads. Furthermore, the male-specific relationship between shorter interbirth intervals and increased ASD risk is consistent with a potentially greater contribution from environmental factors in males versus higher genetic risk in affected females and their families. Understanding the mechanisms driving these sex-differential risk profiles will be useful for treatment development and prevention. [ABSTRACT FROM AUTHOR]

Tourette syndrome (TS) is a neuropsychiatric disorder characterized by recurrent motor and vocal tics, often accompanied by obsessive-compulsive disorder and/or attention-deficit/hyperactivity disorder. While the evidence for a genetic contribution is strong, its exact nature has yet to be clarified fully. There is now mounting evidence that the genetic risks for TS include both common and rare variants and may involve complex multigenic inheritance or, in rare cases, a single major gene. Based on recent progress in many other common disorders with apparently similar genetic architectures, it is clear that large patient cohorts and open-access repositories will be essential to further advance the field. To that end, the large multicenter Tourette International Collaborative Genetics (TIC Genetics) study was established. The goal of the TIC Genetics study is to undertake a comprehensive gene discovery effort, focusing both on familial genetic variants with large effects within multiply affected pedigrees and on de novo mutations ascertained through the analysis of apparently simplex parent-child trios with non-familial tics. The clinical data and biomaterials (DNA, transformed cell lines, RNA) are part of a sharing repository located within the National Institute for Mental Health Center for Collaborative Genomics Research on Mental Disorders, USA, and will be made available to the broad scientific community. This resource will ultimately facilitate better understanding of the pathophysiology of TS and related disorders and the development of novel therapies. Here, we describe the objectives and methods of the TIC Genetics study as a reference for future studies from our group and to facilitate collaboration between genetics consortia in the field of TS. [ABSTRACT FROM AUTHOR]

Dyslexia is a frequent neurodevelopmental learning disorder. To date, nine susceptibility loci have been identified, one of them being DYX9, located in Xq27. We performed the first French SNP linkage study followed by candidate gene investigation in dyslexia by studying 12 multiplex families (58 subjects) with at least two children affected, according to categorical restrictive criteria for phenotype definition. Significant results emerged on Xq27.3 within DYX9. The maximum multipoint LOD score reached 3,884 between rs12558359 and rs454992. Within this region, seven candidate genes were investigated for mutations in exonic sequences ( CXORF1, CXORF51, SLITRK2, FMR1, FMR2, ASFMR1, FMR1NB), all having a role during brain development. We further looked for 5′UTR trinucleotide repeats in FMR1 and FMR2 genes. No mutation or polymorphism co-segregating with dyslexia was found. This finding in French families with Dyslexia showed significant linkage on Xq27.3 enclosing FRAXA, and consequently confirmed the DYX9 region as a robust susceptibility locus. We reduced the previously described interval from 6.8 (DXS1227-DXS8091) to 4 Mb also disclosing a higher LOD score. [ABSTRACT FROM AUTHOR]

The acronym VATER/VACTERL association is used to describe the non-random co-occurrence of vertebral defects (V), anorectal malformations (A), cardiac defects (C), tracheo-esophageal fistula with or without esophageal atresia (TE), renal malformations (R), and limb defects (L). We report a familial case of VATER/VACTERL association in which both the index case and her maternal uncle displayed four major component features of the disorder. A systematic literature search identified 12 previously described familial cases. However, on comparison, both members fulfilled the diagnostic criteria for VATER/VACTERL association only in one instance, and ours is the second such report. Although, a SNP array-based analysis identified no causal genomic alteration, the findings in the present family suggest that genetic factors are implicated in the development of the disorder. [ABSTRACT FROM AUTHOR]

Recent studies suggest that a history of cigarette smoking is a risk factor for multiple sclerosis (MS).We aimed to test the smoking effect in multiplex families, matching for both environmental and genetic factors. In a matched case-control study, 136 MS patients from 106 multiplex MS families were compared with their 204 healthy siblings as controls. Participants completed self-report questionnaires. Conditional logistic regression was used to analyse smoking and MS risk association while controlling for confounding by age and sex. Smoking history was classified in different variables. Within our survey the smoking history of MS patients and the controls did not differ. The odds of MS were comparable for different smoking levels. However, more intense exposure and women showed higher odds ratios, although non-significant. Association studies in families with relatively high genetic loading are unlikely to be confounded by smoking history. [ABSTRACT FROM AUTHOR]

Abstract: Endophenotypes is one emerging strategy in schizophrenia research that is being used to identify the functional importance of genetically transmitted, brain-based deficits present in this disease. Currently, event-related potentials (ERPs) are timely used in this search. Several ERPs, including N400, present deficits in relation to schizophrenia. In order to assess the genetic liability of N400 as a possible endophenotype, a picture semantic matching task (congruent and incongruent pairs of pictures) was performed by 21 unaffected first-degree relatives of patients with schizophrenia, 21 DSM-IV diagnosed schizophrenia probands, and 21 control subjects, matched by age, gender and educational level. Probands and relatives were selected form Multiplex schizophrenia families. Significantly reduced N400 amplitude for congruent categories in N400 was found in probands and relatives in relation to controls. The latency onset and the maximum peak latency of N400 were delayed in both, relatives and probands groups compared to control. The voltage maps of incongruous-minus-congruous difference indicate a more reduced right restricted negativity in probands and relatives, when compared to a widely extended bilateral negativity in controls. No general differences were found between patients and relatives. These results demonstrate an electrophysiological deficit in semantic match processing in clinically unaffected first-degree relatives of patients with schizophrenia, suggesting a possible use of this marker as endophenotype. [Copyright &y& Elsevier]

Abstract: Sustained attention deficits measured by the Continuous Performance Test (CPT) have been proposed as an endophenotype of schizophrenia. However, little is known about whether sustained attention deficits in first-degree relatives of schizophrenic patients are associated with familial loading for schizophrenia. We examined 107 parents and 84 siblings of simplex schizophrenia families as well as 72 parents and 56 siblings of multiplex schizophrenia families, all nonpsychotic, using the Diagnostic Interview for Genetic Studies and two sessions of the CPT (undegraded and degraded). The effect of perceptual load was assessed using the residual of the regression of the degraded score on the undegraded one. Statistical models that can adjust for familial correlations were used to compare the CPT performance of relatives between the two types of families. Siblings from multiplex families exhibited worse performance on the degraded CPT and less proficiency in processing the perceptual load than those from simplex families. No such difference was observed for the parents on either CPT version. We concluded that sustained attention along with perceptual load processing is more impaired in the siblings of schizophrenic patients with high familial loading and that this finding might be useful for future genetic dissection of schizophrenia. [Copyright &y& Elsevier]

We investigated the association of the antibody response to myelin oligodendrocyte glycoprotein (MOG) and myelin basic protein (MBP) with human leukocyte antigen (HLA) class II alleles in 41 patients with sporadic multiple sclerosis (MS) and 12 multiplex MS families. We found significantly increased antibody response to MOG and MBP in MS patients without any difference to asymptomatic relatives. HLA DRB1*04 was associated with IgM reactivity to MOG in MS patients, and DRB1*15 and DRB5 with anti-MOG IgA among asymptomatic relatives. We conclude that antibody responses to MOG and MBP depend on familial background. Moreover, the humoral immune reactivity against MOG is partially under control of certain HLA class II alleles. [Copyright &y& Elsevier]

Lord (1992) published a brief report showing a trend for decreasing nonverbal IQ scores with increasing birth order in a sample of 16 autism multiplex families, and urged replication in a larger sample. In this report, analyses of nonverbal IQ scores for a sample of 144 autism multiplex families indicated that nonverbal IQ scores were significantly lower in secondborn compared with firstborn siblings with autism. This birth order effect was independent of gender as well as the age differences within sib pairs. No such birth order effects were found for social or communicative deficits as measured by the Autism Diagnostic Interview-Revised (ADI-R), but there was a modest tendency for increased scores for ritualistic behaviors for the firstborn sibs. Further, there were no gender differences on nonverbal IQ scores in this sample. Results are discussed in terms of implications for genetic studies of autism. [ABSTRACT FROM AUTHOR]

Known multiple sclerosis (MS) susceptibility variants can only explain half of the disease's estimated heritability, whereas low-frequency and rare variants may partly account for the missing heritability. Thus, here we sought to determine the occurrence of rare functional variants in a large Italian MS multiplex family with five affected members. For this purpose, we combined linkage analysis and next-generation sequencing (NGS)-based whole exome and whole genome sequencing (WES and WGS, respectively). The genetic burden attributable to known common MS variants was also assessed by weighted genetic risk score (wGRS). We found a significantly higher burden of common variants in the affected family members compared to that observed among sporadic MS patients and healthy controls (HCs). We also identified 34 genes containing at least one low-frequency functional variant shared among all affected family members, showing a significant enrichment in genes involved in specific biological processes—particularly mRNA transport—or neurodegenerative diseases. Altogether, our findings point to a possible pathogenic role of different low-frequency functional MS variants belonging to shared pathways. We propose that these rare variants, together with other known common MS variants, may account for the high number of affected family members within this MS multiplex family. [ABSTRACT FROM AUTHOR]

Reflecting on the accompanying article by Jans et al., we draw the following thoughts. Future research on multiplex ADHD families is needed to elucidate mechanisms, timing, and a sequencing of interventions, preferably in treatment naïve participants. Furthermore, in addition to symptom measures, it is likely that multi‐informant measures of functional impairments such as parenting and parent‐child observations may help elucidate the complex mechanisms linking maternal and child ADHD, and eventually lead to more targeted, efficient, and feasible prevention and intervention strategies. [ABSTRACT FROM AUTHOR]