Ellis‐van Creveld syndrome (EvC) is a chondral and ectodermal dysplasia caused by biallelic mutations in the EVC, EVC2 and WDR35 genes. A proportion of cases with clinical diagnosis of EvC, however, do not carry mutations in these genes. To identify the genetic cause of EvC in a cohort of mutation‐negative patients, exome sequencing was undertaken in a family with 3 affected members, and mutation scanning of a panel of clinically and functionally relevant genes was performed in 24 additional subjects with features fitting/overlapping EvC. Compound heterozygosity for the c.2T>C (p.Met1?) and c.662C>T (p.Thr221Ile) variants in DYNC2LI1, which encodes a component of the intraflagellar transport‐related dynein‐2 complex previously found mutated in other short‐rib thoracic dysplasias, was identified in the 3 affected members of the first family. Targeted resequencing detected compound heterozygosity for the same missense variant and a truncating change (p.Val141*) in 2 siblings with EvC from a second family, while a newborn with a more severe phenotype carried 2 DYNC2LI1 truncating variants. Our findings indicate that DYNC2LI1 mutations are associated with a wider clinical spectrum than previously appreciated, including EvC, with the severity of the phenotype likely depending on the extent of defective DYNC2LI1 function.

Deleterious variants of DYNC2H1 gene are associated with a wide spectrum of skeletal ciliopathies (SC). We used targeted parallel sequencing to analyze 25 molecularly unsolved families with different SCs. Deleterious DYNC2H1 variants were found in six sporadic patients and two monozygotic (MZ) twins. Clinical diagnoses included short rib-polydactyly type 3 in two cases, and asphyxiating thoracic dystrophy (ATD) in one case. Remarkably, clinical diagnosis fitted with EvC, mixed ATD/EvC and short rib-polydactyly/EvC phenotypes in three sporadic patients and the MZ twins. EvC/EvC-like features always occurred in compound heterozygotes sharing a previously unreported splice site change (c.6140-5A>G) or compound heterozygotes for two missense variants. These results expand the DYNC2H1 mutational repertoire and its clinical spectrum, suggesting that EvC may be occasionally caused by DYNC2H1 variants presumably acting as hypomorphic alleles.

Introduction: Dystonia type 24 is due to the mutation of the ANO3 gene. It generally consists of craniocervical dystonia associated with tremor; however, other neurological manifestations may also occur. Scientific literature has been expanding on its phenotype over the past few years. Case: Here we present two siblings affected by dystonia 24 associated to a novel missense mutation of the ANO3 gene. Description of their phenotype, with regard to motor and non-motor features, may improve the knowledge on DYT 24. Consistent with previous reports, our patients presented with cranio-cervical involvement, and they also exhibited different severity and phenotypes. However non-motor symptoms were present too. Conclusion: Dystonia 24 spectrum is continuously expanding. This case suggests that the ANO3 missense muta-tion should be sought in all cases of dystonia and isolated tremor and that non-motor symptoms are an integral part of dystonic syndromes. It also shows that clinical and treatment features may vary from patient to patient, even if they may present the same mutation.

Upregulated signal flow through RAS and the mitogen-associated protein kinase (MAPK) cascade is the unifying mechanistic theme of the RASopathies, a family of disorders affecting development and growth. Pathogenic variants in more than 20 genes have been causally linked to RASopathies, the majority having a dominant role in promoting enhanced signaling. Here, we report that SPRED2 loss of function is causally linked to a recessive phenotype evocative of Noonan syndrome. Homozygosity for three different variants-c.187C>T (p.Arg63∗), c.299T>C (p.Leu100Pro), and c.1142_1143delTT (p.Leu381Hisfs∗95)-were identified in four subjects from three families. All variants severely affected protein stability, causing accelerated degradation, and variably perturbed SPRED2 functional behavior. When overexpressed in cells, all variants were unable to negatively modulate EGF-promoted RAF1, MEK, and ERK phosphorylation, and time-course experiments in primary fibroblasts (p.Leu100Pro and p.Leu381Hisfs∗95) documented an increased and prolonged activation of the MAPK cascade in response to EGF stimulation. Morpholino-mediated knockdown of spred2a and spred2b in zebrafish induced defects in convergence and extension cell movements indicating upregulated RAS-MAPK signaling, which were rescued by expressing wild-type SPRED2 but not the SPRED2Leu381Hisfs∗95 protein. The clinical phenotype of the four affected individuals included developmental delay, intellectual disability, cardiac defects, short stature, skeletal anomalies, and a typical facial gestalt as major features, without the occurrence of the distinctive skin signs characterizing Legius syndrome. These features, in part, characterize the phenotype of Spred2-/- mice. Our findings identify the second recessive form of Noonan syndrome and document pleiotropic consequences of SPRED2 loss of function in development.

The expanded CAG repeat number in HTT gene causes Huntington disease (HD), which is a severe, dominant neurodegenerative illness. The accurate determination of the expanded allele size is crucial to confirm the genetic status in symptomatic and presymptomatic at-risk subjects and avoid genetic polymorphism-related false-negative diagnoses. Precise CAG repeat number determination is critical to discriminate the cutoff between unexpanded and intermediate mutable alleles (IAs, 27–35 CAG) as well as between IAs and pathological, low-penetrance alleles (i.e., 36–39 CAG repeats), and it is also critical to detect large repeat expansions causing pediatric HD variants. We analyzed the HTT-CAG repeat number of 14 DNA reference materials and of a DNA collection of 43 additional samples carrying unexpanded, IAs, low and complete penetrance alleles, including large (>60 repeats) and very large (>100 repeats) expansions using a novel triplet-primed PCR-based assay, the AmplideX PCR/CE HTT Kit. The results demonstrate that the method accurately genotypes both normal and expanded HTT-CAG repeat numbers and reveals previously undisclosed and very large CAG expansions >200 repeats. We also show that this technique can improve genetic test reliability and accuracy by detecting CAG expansions in samples with sequence variations within or adjacent to the repeat tract that cause allele drop-outs or inaccuracies using other PCR methods.

Dentato-Rubral-pallidoluysian atrophy (DRPLA) is a rare autosomal, dominant, progressive neurodegenerative disease that causes involuntary movements, mental and emotional problems. DRPLA is caused by a mutation in the ATN1 gene that encodes for an abnormal polyglutamine stretch in the atrophin-1 protein. DRPLA is most common in the Japanese population, where it has an estimated incidence of 2 to 7 per million people. This condition has also been seen in families from North America and Europe. We obtained a reprogrammed iPSC line from a Caucasian patient with a juvenile onset of the disease, carrying 64 CAG repeat expansion in the ATN1 gene.

Objective: Huntington disease (HD) generally manifests in adulthood. Large mutations with CAG repeat expansion in HTT gene may rarely cause juvenile Huntington disease (JHD) in early childhood or adolescence with atypical clinical features, i.e., atypical parkinsonism, if compared to adult patients. Our objective is to characterize the rare occurrence of clinical manifestations in children carrying mutations in the low-mild size, generally causing adult HD with typical choreic movements. Methods: We are following up a subgroup of young subjects with HD mutation who manifested with disabling psychiatric condition since early childhood or adolescence. We are collecting data by the observational studies Registry and ENROLL-HD since 2004. Among 60 JHD patients we are currently following-up, we selected people who carry a mutation in the mild range of CAG expansions (i.e., expected to manifest in adulthood), psychiatric manifestations and no neurological signs or movement disorders suggestive of HD. All patients were genetically (i.e., CAG size analysis) and clinically (i.e., total motor score within the Unified HD Rating Scale) characterized. Results: We found four subjects who showed the characteristics for this analysis. All four subjects presented a CAG expansion size <45 repeats. Two patients manifested a schizophrenia-like disturbance during their adolescence, with the later appearance of motor signs after age 20. In the other two cases, patients presented symptoms of autistic spectrum disorder, since infancy. One of them showed also a schizophrenia-like disturbance and, later, HD onset with motor signs after 20. A 45 year old patient is currently manifesting an autistic disorder in absence of others neurological signs. Conclusion: The description of JHD includes sometimes children with psychiatric manifestations associated with adult motor onset. We advise to pay careful attention to such rare conditions that might represent either psychiatric conditions erroneously classified as JHD or prodromic adult HD cases.

Background Paroxysmal movement disorders are rare and heterogeneous genetic conditions characterized by the recurrence of transient involuntary movements. Phenomenology Shown The phenomenology of a paroxysmal kinesigenic dyskinesia in a young professional athlete. Educational Value Providing basic clinical and genetic elements for the early recognition and diagnosis of a rare movement disorder.

Background Huntington's disease is a rare, neurodegenerative disease caused by an expanded CAG repeat mutation in the huntingtin gene. Compared with adult-onset Huntington's disease, juvenile Huntington's disease (onset <= 20 years) is even rarer and has not been studied extensively. We aimed to further characterise juvenile Huntington's disease by examining the effect of CAG repeat size on disease presentation, progression, and survival. Methods We did a retrospective analysis of patients with juvenile Huntington's disease aged 20 years or younger, according to the length of their CAG repeat and who had disabling psychiatric symptoms (with motor symptoms) or motor symptoms alone, and of patients with adult-onset Huntington's disease manifesting aged 30-60 years with 40 or more CAG repeats, from the REGISTRY and ENROLL-HD platforms and from two institutional databases (Lega Italiana Ricerca Huntington Foundation and the Instituto Neurociencias de Buenos Aires and the Sanatorio de la Trinidad Mitre). Patients with psychiatric but no motor symptoms were excluded. We compared symptoms at onset and longitudinally in patients with juvenile Huntington's disease with highly expanded (HE subgroup) or low expansion (LE subgroup) mutations, grouped by hierarchical clustering analysis. We also compared disease progression (longitudinal change in Unified Huntington's Disease Rating Scale-Total Motor Score) and survival of patients with juvenile and adult-onset Huntington's disease. Findings We extracted medical records from 580 patients entered into the studies or databases between June 23, 2004, and March 31, 2018, of whom 36 patients met our definition of juvenile Huntington's disease and 197 for adult-onset Huntington's disease. According to caregiver reports, gait disturbance was more often a first presenting symptom in the HE subgroup (eight [80%] of 10 patients) than in the LE subgroup (seven [27%] of 26 patients; p=0.0071), whereas loss of hand dexterity was more common in the LE subgroup (11 [42%] of 26 patients) than in the HE subgroup (0 [0%] of 10 patients; p=0.0160). Compared with the LE subgroup, development delay (0 [0%] in the LE subgroup vs nine [90%] in the HE subgroup; p<0.0001), severe gait impairment (nine [35%] in the LE subgroup vs nine [90%] in the HE subgroup; p=0.0072), and seizures (three [11%] in the LE subgroup vs eight [80%] in the HE subgroup; p<0.0001) prevailed over time in the HE subgroup. Disease progression was more rapid in juvenile Huntington's disease (n=14) than in adult-onset Huntington's disease (n=52; generalised estimating equation model, p=0.0003). Of 121 deceased patients, median survival was shorter in the juvenile Huntington's disease (n=17) cohort than in adult-onset Huntington's disease (n=104) cohort (hazard ratio 2.18 [95% CI 1.08-4.40]; p=0.002). Interpretation Patients with HE juvenile Huntington's disease differ clinically from patients with LE juvenile Huntington's disease or adult-onset Huntington's disease, suggesting reclassification of this particularly aggressive form of Huntington's disease might be required. Copyright (C) 2018 Elsevier Ltd. All rights reserved.

Huntington's disease (HD) is an incurable, autosomal dominant, hereditary neurodegenerative disorder that typically manifests itself in midlife. This pathology is linked to the deregulation of multiple, as yet unknown, cellular processes starting before HD onset. A human iPS cell line was generated from skin fibroblasts of a subject at the presymptomatic life stage, carrying a polyglutamine expansion in HTT gene codifying Huntingtin protein. The iPSC line contained the expected CAG expansion, expressed the expected pluripotency markers, displayed in vivo differentiation potential to the three germ layers and had a normal karyotype.

Huntington Disease (HD) is an autosomal dominant disorder characterized by motor, cognitive and behavioral features caused by a CAG expansion in the HTT gene beyond 35 repeats. The juvenile form (JHD) may begin before the age of 20years and is associated with expanded alleles as long as 60 or more CAG repeats. In this study, induced pluripotent stem cells were generated from skin fibroblasts of a 8-year-old child carrying a large size mutation of 84 CAG repeats in the HTT gene. HD appeared at age 3 with mixed psychiatric (i.e. autistic spectrum disorder) and motor (i.e. dystonia) manifestations.

Atrioventricular septal defect (AVSD) may occur as part of a complex disorder (e.g., Down syndrome, heterotaxy), or as isolate cardiac defect. Multiple lines of evidence support a role of calcineurin/NFAT signaling in AVSD, and mutations in CRELD1, a protein functioning as a regulator of calcineurin/NFAT signaling have been reported in a small fraction of affected subjects. In this study, 22 patients with isolated AVSD and 38 with AVSD and heterotaxy were screened for NFATC1 gene mutations. Sequence analysis identified three missense variants in three individuals, including a subject with isolated AVSD [p.(Ala367Val)], an individual with AVSD and heterotaxy [p.(Val210Met)], and a subject with AVSD, heterotaxy, and oculo-auriculo-vertebral spectrum (OAVS) [p.(Ala696Thr)], respectively. The latter was also heterozygous for a missense change in TBX1 [p.(Pro86Leu)]. Targeted resequencing of genes associated with AVSD, heterotaxy, or OAVS excluded additional hits in the three mutation-positive subjects. Functional characterization of NFATC1 mutants documented defective nuclear translocation and decreased transcriptional transactivation activity. When expressed in zebrafish, the three NFATC1 mutants caused cardiac looping defects and altered atrioventricular canal patterning, providing evidence of their functional relevance in vivo. Our findings support a role of defective NFATC1 function in the etiology of isolated and heterotaxy-related AVSD.

Background Huntington’s disease (HD) prevalence is variable and depends on genetic background. However, culture, environment and other, yet unknown, biological factors may also play a role in determining its frequency. In Italy we estimate a prevalence of 11/100.000 (Squitieri et al., 2016). Methods LIRH Foundation started to collect clinical and genealogical data together with DNA samples from patients and family members since 2001. Recently, we got in touch with a family from Calabria, Southern Italy, showing a high number of interrelationships and consequent increased risk of transmission of the mutation among people. Results The family includes about 25 affected people with ascertained HD and hundreds at risk. However, there were two generations of people with homozygous CAG repeat expansion due to two intermarriages of mutation carrier people. The main kindred showed a homozygous mother married with a heterozygous father and 5 children whose four had an homozygous condition. They showed a different HD stage and were included into ENROLL-HD. These people had several 100% risk children. Conclusion Nevertheless the large experience and the number of publications on genetic and psychological counseling in HD, the scientific community remains still unprepared on how to communicate such unusual risk of HD transmission. These conditions, moreover, contribute to an unpredictable frequency of the disease in some geographical areas.

Juvenile Onset Huntington's Disease (JOHD) is a rare variant of HD withage of onset ≤20 years, accounting for 3–10% of all HD patients. The rarity occurrence of JOHD cases, who severely progress towards mental and physical disability with atypical clinical manifestations compared to classical HD, are responsible of general lack of knowledge about this variant. We obtained a fully reprogrammed iPS cell line from fibroblasts of a JOHD patient carrying 65 CAG repeats and age at onset at age 15. At the biopsy time, the patient showed an advanced stage after 10 years of disease.

Objective: Gingival overgrowth is a side effect associated with some distinct classes of drugs, such as anticonvulsants, immunosuppressants, and calcium channel blockers. One of the main drugs associated with gingival overgrowth is the antiepileptic phenytoin, which affects gingival tissues by altering extracellular matrix metabolism. It has been shown that mutation of human SOSI gene is responsible for a rare hereditary gingival fibromatosis type 1, a benign gingival overgrowth. The aim of the present study is to evaluate the possible contribution of SOS1 mutation to gingival overgrowth-related phenotype.Design: We selected and screened for mutations a group of 24 epileptic patients who experienced significant gingival overgrowth following phenytoin therapy. Mutation scanning was carried out by denaturing high-performance liquid chromatography analysis of the entire coding region of the SOS1 gene. Novel identified variants were analyzed in-silico by using Alamut Visual mutation interpretation software, and comparison with normal control group was done.Results: Mutation scanning of the entire coding sequence of SOSI gene identified seven intronic variants and one new exonic substitution (c.138G > A). The seven common intronic variants were not considered to be of pathogenic importance. The exonic substitution c.138G > A was found to be absent in 100 ethnically matched normal control chromosomes, but was not expected to have functional significance based on prediction bioinformatics tools.Conclusions: This study represents the first mutation analysis of the SOSI gene in phenytoin-induced gingival overgrowth epileptic patients. Present results suggest that obvious pathogenic mutations in the SOSI gene do not represent a common mechanism underlying phenytoin-induced gingival overgrowth in epileptic patients; other mechanisms are likely to be involved in the pathogenesis of this drug-induced phenotype.