Combined exome and whole transcriptome sequencing identifies a de novo intronic SRCAP variant causing DEHMBA syndrome with severe sleep disorder.

Rare heterozygous variants in exons 33-34 of the SRCAP gene are associated with Floating-Harbor syndrome and have a dominant-negative mechanism of action. At variance, heterozygous null alleles falling in other parts of the same gene cause developmental delay, hypotonia, musculoskeletal defects, and behavioral abnormalities (DEHMBA) syndrome. We report an 18-year-old man with DEHMBA syndrome and obstructive sleep apnea, who underwent exome sequencing (ES) and whole transcriptome sequencing (WTS) on peripheral blood. Trio analysis prioritized the de novo heterozygous c.5658+5 G > A variant. WTS promptly demostrated four different abnormal transcripts affecting >40% of the reads, three of which leading to a frameshift. This study demonstrated the efficacy of a combined ES-WTS approach in solving undiagnosed cases. We also speculated that sleep respiratory disorder may be an underdiagnosed complication of DEHMBA syndrome.

Nucleotide substitutions at the p.Gly117 and p.Thr180 mutational hot-spots of SKI alter molecular dynamics and may affect cell cycle.

Heterozygous deleterious variants in SKI cause Shprintzen-Goldberg Syndrome, which is mainly characterized by craniofacial features, neurodevelopmental disorder and thoracic aorta dilatations/aneurysms. The encoded protein is a member of the transforming growth factor beta signaling. Paucity of reported studies exploring the SGS molecular pathogenesis hampers disease recognition and clinical interpretation of private variants. Here, the unpublished c.349G>A, p.[Gly117Ser] and the recurrent c.539C>T, p.[Thr180Met] SKI variants were studied combining in silico and in vitro approach. 3D comparative modeling and calculation of the interaction energy predicted that both variants alter the SKI tertiary protein structure and its interactions. Computational data were functionally corroborated by the demonstration of an increase of MAPK phosphorylation levels and alteration of cell cycle in cells expressing the mutant SKI. Our findings confirmed the effects of SKI variants on MAPK and opened the path to study the role of perturbations of the cell cycle in SGS.

Placing joint hypermobility in context: traits, disorders and syndromes.

BACKGROUND: Joint hypermobility (JHM) is a common physical trait. It may occur alone or in combination with musculoskeletal (MSK) pain, outside or within more complex phenotypes. Hypermobility spectrum disorders (HSD) are diagnosed in individuals with JHM and related MSK pain, when an alternative diagnosis cannot be identified. Conversely, the Ehlers-Danlos syndrome (EDS) encompasses a group of rare hereditary connective tissue disorders featuring JHM along with other pleiotropic manifestations. The 2017 EDS Classification identifies 13 different subtypes. Hypermobile EDS (HEDS) is the only EDS variant still lacking a confirmatory test. SOURCES OF DATA: Literature was reviewed searching for the most relevant papers related to key arguments. Particular attention was focused on papers published after the 2017 Classification. AREAS OF AGREEMENT: Definition, epidemiology, assessment tools and patterns of JHM are presented. The morbid nature of the 2017 EDS Classification and of the 'spectrum' is also illustrated. AREAS OF CONTROVERSY: We discuss current limitations and disagreements concerning the 'spectrum', HSD and HEDS. GROWING POINTS: In the clinical context, elucidation of the pathophysiology of pain related to JHM should develop in parallel with the analysis of pleiotropic manifestations of syndromes with JHM. AREAS TIMELY FOR DEVELOPING RESEARCH: Future challenges concerning classification, nosology, diagnosis and management of JHM, EDS and related disorders are discussed.

Specifications and validation of the ACMG/AMP criteria for clinical interpretation of sequence variants in collagen genes associated with joint hypermobility.

Deleterious variants in collagen genes are the most common cause of hereditary connective tissue disorders (HCTD). Adaptations of the American College of Medical Genetics and Genomics/Association for Molecular Pathology (ACMG/AMP) criteria are still lacking. A multidisciplinary team was set up for developing specifications of the ACMG/AMP criteria for COL1A1, COL1A2, COL2A1, COL3A1, COL5A1, COL5A2, COL11A1, COL11A2 and COL12A1, associated with various forms of HCTD featuring joint hypermobility, which is becoming one of the most common reasons of referral for molecular testing in this field. Such specifications were validated against 209 variants, and resulted effective for classifying as pathogenic and likely pathogenic null alleles without downgrading of the PVS1 level of strength and recurrent Glycine substitutions. Adaptations of selected criteria reduced uncertainties on private Glycine substitutions, intronic variants predicted to affect the splicing, and null alleles with a downgraded PVS1 level of strength. Segregation and multigene panel sequencing data mitigated uncertainties on non-Glycine substitutions by the attribution of one or more benignity criteria. These specifications may improve the clinical utility of molecular testing in HCTD by reducing the number of variants with neutral/conflicting interpretations. Close interactions between laboratory and clinicians are crucial to estimate the a priori utility of molecular test and to improve medical reports.

Opitz syndrome: improving clinical interpretation of intronic variants in MID1 gene.

BACKGROUND: Loss-of-function variants in MID1 are the most common cause of Opitz G/BBB syndrome (OS). The interpretation of intronic variants affecting the splicing is a rising issue in OS. METHODS: Exon sequencing of a 2-year-old boy with OS showed that he was a carrier of the de novo c.1286-10G>T variant in MID1. In silico predictions and minigene assays explored the effect of the variant on splicing. The minigene approach was also applied to two previously identified MID1 c.864+1G>T and c.1285+1G>T variants. RESULTS: Minigene assay demonstrated that the c.1286-10G>T variant generated the inclusion of eight nucleotides that predicted generation of a frameshift. The c.864+1G>T and c.1285+1G>T variants resulted in an in-frame deletion predicted to generate a shorter MID1 protein. In hemizygous males, this allowed reclassification of all the identified variants from "of unknown significance" to "likely pathogenic." CONCLUSIONS: Minigene assay supports functional effects from MID1 intronic variants. This paves the way to the introduction of similar second-tier investigations in the molecular diagnostics workflow of OS. IMPACT: Causative intronic variants in MID1 are rarely investigated in Opitz syndrome. MID1 is not expressed in blood and mRNA studies are hardly accessible in routine diagnostics. Minigene assay is an alternative for assessing the effect of intronic variants on splicing. This is the first study characterizing the molecular consequences of three MID1 variants for diagnostic purposes and demonstrating the efficacy of minigene assays in supporting their clinical interpretation. Review of the criteria according to the American College of Medical Genetics reassessed all variants as likely pathogenic.

Generation of the induced pluripotent stem cell line UNIBSi017-A from an individual with cardiospondylocarpofacial syndrome and the MAP3K7 c.737-7A > G variant.

TAK1 is a serine threonine kinase that mediates signal transduction induced by TGFß and bone morphogenetic proteins, and controls a variety of cell functions by modulating the downstream activation of NF-kkB, JNK, and p38. Heterozygous variants in the coding MAP3K7 gene cause the cardiospondylocarpofacial syndrome, characterized by various abnormalities. Skin fibroblasts derived from a patient carrying the MAP3K7 c.737-7A>G heterozygous variant were reprogrammed using Sendai viral vector system carrying the Yamanaka factors. The generated induced pluripotent stem cells (iPSC) line retained the original genotype, expressed pluripotency markers, and differentiated into cells of the three germ layers.

A novel homozygous variant in COX5A causes an attenuated phenotype with failure to thrive, lactic acidosis, hypoglycemia, and short stature.

Genetic defect in the nuclear encoded subunits of cytochrome c oxidase are very rare. To date, most deleterious variants affect the mitochondrially encoded subunits of complex IV and the nuclear genes encoded for assembly factors. A biallelic pathogenic variant in the mitochondrial complex IV subunit COX5A was previously reported in a couple of sibs with failure to thrive, lactic acidosis and pulmonary hypertension and a lethal phenotype. Here, we describe a second family with a 11-year-old girl presenting with failure to thrive, lactic acidosis, hypoglycemia and short stature. Clinical exome revealed the homozygous missense variant c.266 T > G in COX5A, which produces a drop of the corresponding protein and a reduction of the COX activity. Compared to the previous observation, this girl showed an attenuated metabolic derangement without involvement of the cardiovascular system and neurodevelopment. Our observation confirms that COX5A recessive variants may cause mitochondrial disease and expands the associated phenotype to less severe presentations.

Loss-of-function variants in exon 4 of TAB2 cause a recognizable multisystem disorder with cardiovascular, facial, cutaneous, and musculoskeletal involvement.

PURPOSE: This study aimed to describe a multisystemic disorder featuring cardiovascular, facial, musculoskeletal, and cutaneous anomalies caused by heterozygous loss-of-function variants in TAB2. METHODS: Affected individuals were analyzed by next-generation technologies and genomic array. The presumed loss-of-function effect of identified variants was assessed by luciferase assay in cells transiently expressing TAB2 deleterious alleles. In available patients' fibroblasts, variant pathogenicity was further explored by immunoblot and osteoblast differentiation assays. The transcriptomic profile of fibroblasts was investigated by RNA sequencing. RESULTS: A total of 11 individuals from 8 families were heterozygotes for a novel TAB2 variant. In total, 7 variants were predicted to be null alleles and 1 was a missense change. An additional subject was heterozygous for a 52 kb microdeletion involving TAB2 exons 1 to 3. Luciferase assay indicated a decreased transcriptional activation mediated by NF-κB signaling for all point variants. Immunoblot analysis showed a reduction of TAK1 phosphorylation while osteoblast differentiation was impaired. Transcriptomic analysis identified deregulation of multiple pleiotropic pathways, such as TGFß-, Ras-MAPK-, and Wnt-signaling networks. CONCLUSION: Our data defined a novel disorder associated with loss-of-function or, more rarely, hypomorphic alleles in a restricted linker region of TAB2. The pleiotropic manifestations in this disorder partly recapitulate the 6q25.1 (TAB2) microdeletion syndrome and deserve the definition of cardio-facial-cutaneous-articular syndrome.

Electroclinical features of MEF2C haploinsufficiency-related epilepsy: A multicenter European study.

PURPOSE: Epilepsy is a main manifestation in the autosomal dominant mental retardation syndrome caused by heterozygous variants in MEF2C. We aimed to delineate the electro-clinical features and refine the genotype-phenotype correlations in patients with MEF2C haploinsufficiency. METHODS: We thoroughly investigated 25 patients with genetically confirmed MEF2C-syndrome across 12 different European Genetics and Epilepsy Centers, focusing on the epileptic phenotype. Clinical features (seizure types, onset, evolution, and response to therapy), EEG recordings during waking/sleep, and neuroimaging findings were analyzed. We also performed a detailed literature review using the terms "MEF2C", "seizures", and "epilepsy". RESULTS: Epilepsy was diagnosed in 19 out of 25 (~80%) subjects, with age at onset <30 months. Ten individuals (40%) presented with febrile seizures and myoclonic seizures occurred in ~50% of patients. Epileptiform abnormalities were observed in 20/25 patients (80%) and hypoplasia/partial agenesis of the corpus callosum was detected in 12/25 patients (~50%). Nine patients harbored a 5q14.3 deletion encompassing MEF2C and at least one other gene. In 7 out of 10 patients with myoclonic seizures, MIR9-2 and LINC00461 were also deleted, whereas ADGRV1 was involved in 3/4 patients with spasms. CONCLUSION: The epileptic phenotype of MEF2C-syndrome is variable. Febrile and myoclonic seizures are the most frequent, usually associated with a slowing of the background activity and irregular diffuse discharges of frontally dominant, symmetric or asymmetric, slow theta waves with interposed spike-and-waves complexes. The haploinsufficiency of ADGRV1, MIR9-2, and LINC00461 likely contributes to myoclonic seizures and spasms in patients with MEF2C syndrome.

Craniosynostosis is a feature of CHD7-related CHARGE syndrome.

CHARGE syndrome is a rare genetic multiple-malformation disorder characterized by wide phenotypic variability. It is often caused by heterozygous variants in CHD7 and, more rarely, SEMA3E. Although craniofacial alterations are frequent in this condition, to date craniosynostosis is not considered part of the clinical spectrum. Here, we report bi-coronal craniosynostosis in a newborn affected by CHARGE syndrome caused by the de novo heterozygous c.6157C>T, p.(Arg2053*) CHD7 variant. We found two additional subjects in the literature with different craniosynostoses and distinct CHD7 alterations. The inclusion of CHD7-related CHARGE syndrome in the group of rare causes of syndromic craniosynostoses is proposed.

Review of clinical and molecular variability in autosomal recessive cutis laxa 2A.

ATP6V0A2-related cutis laxa, also known as autosomal recessive cutis laxa type 2A (ARCL2A), is a subtype of hereditary cutis laxa originally characterized by skin, skeletal, and neurological involvement, and a combined defect of N-glycosylation and O-glycosylation. The associated clinical spectrum subsequently expanded to a less severe phenotype dominated by cutaneous involvement. At the moment, ARCL2A was described in a few case reports and series only. An Italian adult woman ARCL2A with a phenotype restricted to skin and the two novel c.3G>C and c.1101dup ATP6V0A2 variants has been reported. A systematic literature review allowed us to identify 69 additional individuals from 64 families. Available data were scrutinized in order to describe the clinical and molecular variability of ARCL2A. About 78.3% of known variants were predicted null alleles, while 11 were missense and 2 affected noncanonical splice sites. Age at ascertainment appeared as the unique phenotypic discriminator with earlier age more commonly associated with facial dysmorphism (p .02), high/cleft palate (p .005), intellectual disability/global developmental delay (p .013), and seizures (p .024). No specific genotype-phenotype correlations were identified. This work confirmed the existence of an attenuated phenotype associated with ATP6V0A2 biallelic variants and offers an updated critique to the clinical and molecular variability of ARCL2A.

Clinical presentation and molecular characterization of a novel patient with variant POC1A-related syndrome.

Biallelic pathogenic variants in POC1A result in SOFT (Short-stature, Onychodysplasia, Facial-dysmorphism, and hypoTrichosis) and variant POC1A-related (vPOC1A) syndromes. The latter, nowadays described in only two unrelated subjects, is associated with a restricted spectrum of variants falling in exon 10, which is naturally skipped in a specific POC1A mRNA. The synthesis of an amount of a POC1A isoform from this transcript in individuals with vPOC1A syndrome has been believed as the likely explanation for such a genotype-phenotype correlation. Here, we illustrate the clinical and molecular findings in a woman who resulted to be compound heterozygous for a recurrent frameshift variant in exon 10 and a novel variant in exon 9 of POC1A. Phenotypic characteristics of this woman included severe hyperinsulinemic dyslipidemia, acanthosis nigricans, moderate growth restriction, and dysmorphisms. These manifestations overlap the clinical features of the two previously published individuals with vPOC1A syndrome. RT-PCR analysis on peripheral blood and subsequent sequencing of the obtained amplicons demonstrated a variety of POC1A alternative transcripts that resulted to be expressed in the proband, in the healthy mother, and in controls. We illustrate the possible consequences of the two POC1A identified variants in an attempt to explain pleiotropy in vPOC1A syndrome.

Exon-Trapping Assay Improves Clinical Interpretation of COL11A1 and COL11A2 Intronic Variants in Stickler Syndrome Type 2 and Otospondylomegaepiphyseal Dysplasia.

Stickler syndrome (SS) is a hereditary connective tissue disorder affecting bones, eyes, and hearing. Type 2 SS and the SS variant otospondylomegaepiphyseal dysplasia (OSMED) are caused by deleterious variants in COL11A1 and COL11A2, respectively. In both genes, available database information indicates a high rate of potentially deleterious intronic variants, but published evidence of their biological effect is usually insufficient for a definite clinical interpretation. We report four previously unpublished intronic variants in COL11A1 (c.2241 + 5G>T, c.2809 - 2A>G, c.3168 + 5G>C) and COL11A2 (c.4392 + 1G>A) identified in type 2 SS/OSMED individuals. The pathogenic effect of these variants was first predicted in silico and then investigated by an exon-trapping assay. We demonstrated that all variants can induce exon in-frame deletions, which lead to the synthesis of shorter collagen XI α1 or 2 chains. Lacking residues are located in the α-triple helical region, which has a crucial role in regulating collagen fibrillogenesis. In conclusion, this study suggests that these alternative COL11A1 and COL11A2 transcripts might result in aberrant triple helix collagen. Our approach may help to improve the diagnostic molecular pathway of COL11-related disorders.

Insights into the molecular pathogenesis of cardiospondylocarpofacial syndrome: MAP3K7 c.737-7A > G variant alters the TGFß-mediated α-SMA cytoskeleton assembly and autophagy.

Transforming growth factor beta-activated kinase 1 (TAK1) is a highly conserved kinase protein encoded by MAP3K7, and activated by multiple extracellular stimuli, growth factors and cytokines. Heterozygous variants in MAP3K7 cause the cardiospondylocarpofacial syndrome (CSCFS) which is characterized by short stature, dysmorphic facial features, cardiac septal defects with valve dysplasia, and skeletal anomalies. CSCFS has been described in seven patients to date and its molecular pathogenesis is only partially understood. Here, the functional effects of the MAP3K7 c.737-7A > G variant, previously identified in a girl with CSCFS and additional soft connective tissue features, were explored. This splice variant generates an in-frame insertion of 2 amino acid residues in the kinase domain of TAK1. Computational analysis revealed that this in-frame insertion alters protein dynamics in the kinase activation loop responsible for TAK1 autophosphorylation after binding with its interactor TAB1. Co-immunoprecipitation studies demonstrate that the ectopic expression of TAK1-mutated protein impairs its ability to physically bind TAB1. In patient's fibroblasts, MAP3K7 c.737-7A > G variant results in reduced TAK1 autophosphorylation and dysregulation of the downstream TAK1-dependent signaling pathway. TAK1 loss-of-function is associated with an impaired TGFß-mediated α-SMA cytoskeleton assembly and cell migration, and defective autophagy process. These findings contribute to our understanding of the molecular pathogenesis of CSCFS and might offer the rationale for the design of novel therapeutic targets.

COL1-related overlap disorder: A novel connective tissue disorder incorporating the osteogenesis imperfecta/Ehlers-Danlos syndrome overlap.

The 2017 classification of Ehlers-Danlos syndromes (EDS) identifies three types associated with causative variants in COL1A1/COL1A2 and distinct from osteogenesis imperfecta (OI). Previously, patients have been described with variable features of both disorders, and causative variants in COL1A1/COL1A2; but this phenotype has not been included in the current classification. Here, we expand and re-define this OI/EDS overlap as a missing EDS type. Twenty-one individuals from 13 families were reported, in whom COL1A1/COL1A2 variants were found after a suspicion of EDS. None of them could be classified as affected by OI or by any of the three recognized EDS variants associated with COL1A1/COL1A2. This phenotype is dominated by EDS-related features. OI-related features were limited to mildly reduced bone mass, occasional fractures and short stature. Eight COL1A1/COL1A2 variants were novel and five recurrent with a predominance of glycine substitutions affecting residues within the procollagen N-proteinase cleavage site of α1(I) and α2(I) procollagens. Selected variants were investigated by biochemical, ultrastructural and immunofluorescence studies. The pattern of observed changes in the dermis and in vitro for selected variants was more typical of EDS rather than OI. Our findings indicate the existence of a wider recognizable spectrum associated with COL1A1/COL1A2.

TAB2 c.1398dup variant leads to haploinsufficiency and impairs extracellular matrix homeostasis.

Transforming growth factor ß-activated kinase 1 (TAK1) mediates multiple biological processes through the nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) and the mitogen-activated protein kinase (MAPK) signaling pathways. TAK1 activation is tightly regulated by its binding partners (TABs). In particular, binding with TAB2 is crucial for cardiovascular development and extracellular matrix (ECM) homeostasis. In our previous work, we reported a novel multisystem disorder associated with the heterozygous TAB2 c.1398dup variant. Here, we dissect the functional effects of this variant in order to understand its molecular pathogenesis. We demonstrate that TAB2 c.1398dup considerably undergoes to nonsense-mediated messenger RNA decay and encodes a truncated protein that loses its ability to bind TAK1. We also show an alteration of the TAK1 autophosphorylation status and of selected downstream signaling pathways in patients' fibroblasts. Immunofluorescence analyses and ECM-related polymerase chain reaction-array panels highlight that patient fibroblasts display ECM disorganization and altered expression of selected ECM components and collagen-related pathways. In conclusion, we deeply dissect the molecular pathogenesis of the TAB2 c.1398dup variant and show that the resulting phenotype is well explained by TAB2 loss-of-function. Our data also offer initial insights on the ECM homeostasis impairment as a molecular mechanism probably underlying a multisystem disorder linked to TAB2.

Characterization of Two Novel Intronic Variants Affecting Splicing in FBN1-Related Disorders.

FBN1 encodes fibrillin 1, a key structural component of the extracellular matrix, and its variants are associated with a wide range of hereditary connective tissues disorders, such as Marfan syndrome (MFS) and mitral valve-aorta-skeleton-skin (MASS) syndrome. Interpretations of the genomic data and possible genotype-phenotype correlations in FBN1 are complicated by the high rate of intronic variants of unknown significance. Here, we report two unrelated individuals with the FBN1 deep intronic variants c.6872-24T>A and c.7571-12T>A, clinically associated with MFS and MASS syndrome, respectively. The individual carrying the c.6872-24T>A variant is positive for aortic disease. Both individuals lacked ectopia lentis. In silico analysis and subsequent mRNA study by RT-PCR demonstrated the effect of the identified variant on the splicing process in both cases. The c.6872-24T>A and c.7571-12T>A variants generate the retention of intronic nucleotides and lead to the introduction of a premature stop codon. This study enlarges the mutation spectrum of FBN1 and points out the importance of intronic sequence analysis and the need for integrative functional studies in FBN1 diagnostics.

Cardiac valvular Ehlers-Danlos syndrome is a well-defined condition due to recessive null variants in COL1A2.

Cardiac valvular Ehlers-Danlos syndrome (EDS) is a rare EDS subtype, caused by specific recessive variants in the gene encoding pro-α2-chain of type I collagen (COL1A2). Cardiac valvular EDS is mainly characterized by generalized/peripheral joint hypermobility, moderate-severe cardiac valvular disease, skin hyperextensibility and other minor soft tissues features. Only five molecularly confirmed patients have been reported to date. Here, we describe two additional affected sisters, who share the homozygous c.3601G>T nonsense variant in COL1A2. Clinical data and literature review allowed to better define the clinical spectrum of cardiac valvular EDS which now emerges as a more recognizable EDS variant with progressive heart valve disease firstly affecting the mitral valve. Possibly distinguishing features include bilateral flatfeet with hindfoot pronation, lower eyelid ptosis and hypoplasia of the interphalangeal creases. The absence of bone fragility in our patients indicates that cardiac valvular EDS is also separated from patients with autosomal recessive osteogenesis imperfecta and variants in COL1A2, as well as from individuals with autosomal dominant osteogenesis imperfecta and severe cardiac valvular disease.

Severity classes in adults with hypermobile Ehlers-Danlos syndrome/hypermobility spectrum disorders: a pilot study of 105 Italian patients.

OBJECTIVES: This study is aimed at identifying discrete severity classes among adults with hypermobile Ehlers-Danlos syndrome (hEDS)/hypermobility spectrum disorders (HSD). METHODS: Subjects were selected according to the old and new nomenclatures and all completed a set of questionnaires exploring pain, fatigue, dysautonomic symptoms, coordination and attention/concentration deficits and quality of life in general. Data were investigated by hierarchical clustering on principal components. Cluster comparisons were then performed by using the two-sample unpaired t test and the standardized mean difference was reported as a measure of effect size. Conditional classification tree analysis and multivariable logistic regression were carried out in order to identify the profiles that were at higher risk to belong to the more severe cluster. Weighted linear combination was used to identify a numerical score measuring this risk. RESULTS: A total of 105 patients were selected and distributed in two distinct severity groups. These groups were statistically separated on the basis of 47 of 59 items/characteristics. One group featured the worse values of most questionnaire items (complex/severe cluster) and the other was dominated by the better values (simplex/milder cluster). Only three items were able to stratify patients according to their risk to belong to the complex cluster. A severity score was then constructed on these three items. CONCLUSION: Adults with hEDS/HSD can be separated in two severity classes, which do not mirror either the old or new criteria for hEDS. The identified severity score could allow a bi-dimensional approach to adults with hEDS/HSD for optimal management planning.

Italian validation of the functional difficulties questionnaire (FDQ-9) and its correlation with major determinants of quality of life in adults with hypermobile Ehlers-Danlos syndrome/hypermobility spectrum disorder.

The 2017 nosology defines the new criteria for hypermobile Ehlers-Danlos syndrome (hEDS), which is now considered one end of a continuous spectrum encompassing isolated, nonsyndromic joint hypermobility (JH) and hypermobility spectrum disorders (HSDs). Preliminary data indicate a link between JH and neurodevelopmental disorders and, in particular, developmental coordination disorder (DCD) in children. Assessing DCD in adults is difficult and the recently described functional difficulties questionnaire 9 (FDQ-9) is one of the few available tools. The aims of this study are to (a) validate FDQ-9 written in Italian and present normal values in 230 Italian controls; (b) explore the relationship of FDQ-9 with the brief pain inventory, composite autonomic symptom score 31, multidimensional fatigue inventory, attention deficit/hyperactivity disorder self-report version 1.1, and the SF-36 for quality of life in 105 Italian adults with hEDS/HSD. Validation of the FDQ-9 in Italian was carried out by translation, cross-cultural adaptation and test/retest reliability analysis. A case-control study was performed comparing the FDQ-9 outcome between 105 patients and 105 sex- and age-matched controls. Fifty-nine percent of the patients resulted positive compared to the 3.8% of controls (p value < .00001). In patients, FDQ-9 positive result associated with positive attention deficit/hyperactivity disorder self-report version 1.1 (OR = 4.04). Multivariate regression analysis comparing FDQ-9 with the other questionnaires demonstrated a strong association between positive FDQ-9 and the number of painful joints. Our preliminary data open wider management and therapeutic perspectives for coordination difficulties in hypermobile individuals.