Wilson Disease

The volume and structural covariance network of thalamic nuclei in patients with Wilson's disease: an investigation of the association with neurological impairment

OBJECTIVE

This study aimed to examine the volumes of thalamic nuclei and the intrinsic thalamic network in patients with Wilson's disease (WDs), and to explore the correlation between these volumes and the severity of neurological symptoms.

METHODS

A total of 61 WDs and 33 healthy controls (HCs) were included in the study. The volumes of 25 bilateral thalamic nuclei were measured using structural imaging analysis with Freesurfer, and the intrinsic thalamic network was evaluated through structural covariance network (SCN) analysis.

RESULTS

The results indicated that multiple thalamic nuclei were smaller in WDs compared to HCs, including mediodorsal medial magnocellular (MDm), anterior ventral (AV), central median (CeM), centromedian (CM), lateral geniculate (LGN), limitans-suprageniculate (L-Sg), reuniens-medial ventral (MV), paracentral (Pc), parafascicular (Pf), paratenial (Pt), pulvinar anterior (PuA), pulvinar inferior (PuI), pulvinar medial (PuM), ventral anterior (VA), ventral anterior magnocellular (VAmc), ventral lateral anterior (VLa), ventral lateral posterior (VLp), ventromedial (VM), ventral posterolateral (VPL), and right middle dorsal intralaminar (MDI). The study also found a negative correlation between the UWDRS scores and the volume of the right MDm. The intrinsic thalamic network analysis showed abnormal topological properties in WDs, including increased mean local efficiency, modularity, normalized clustering coefficient, small-world index, and characteristic path length, and a corresponding decrease in mean node betweenness centrality. WDs with cerebral involvement had a lower modularity compared to HCs.

CONCLUSIONS

The findings suggest that the majority of thalamic nuclei in WDs exhibit significant volume reduction, and the atrophy of the right MDm is closely related to the severity of neurological symptoms. The intrinsic thalamic network in WDs demonstrated abnormal topological properties, indicating a close relationship with neurological impairment.

Wilson Disease in Children in the Eastern Region of Morocco: Analysis of 24 Cases

Wilson's disease (WD), or "hepato-lenticular degeneration," is a rare genetic disorder of autosomal recessive inheritance causing toxic tissue accumulation of copper, mainly in the liver, brain, and cornea. Its phenotypic and genotypic heterogeneity characterizes it. This study aimed to clarify the clinical features and spectrum of Wilson's disease in children from the eastern region of Morocco and to study the evolutionary profile and survival in this population while discussing and highlighting the various diagnostic and therapeutic difficulties encountered in the management of WD in our context. This retrospective study encompassed 24 children diagnosed with Wilson's disease, selected from the gastroenterology-hepatology and pediatric nutrition units at Mohamed VI University Hospital in Oujda, Morocco, over a span of nine years, from January 2015 to November 2023. Our series results show 14 boys and 10 girls; the median age of discovery was 11 years, with extremes ranging from 18 months to 15 years. The consanguinity was found in 13 patients. Clinically, the edemato-ascitic syndrome was noted in 14 patients with an alteration of the general state; icterus was found in 13 patients; signs of portal hypertension were present in six patients; and neurological signs in seven cases. Skin manifestations occurred in three cases, and arthralgia in three cases. Six children were diagnosed on the occasion of a family screening. Biologically, hepatic cytolysis was found in 20 patients, with signs of hepatocellular failure in 15 cases. Hemolytic anemia was present in nine patients. Ceruloplasminemia was decreased in 21 patients and cupremia in 19 patients. Cupruria was increased in 22 cases. The Kayser-Fleicher ring was found in 10 cases. Abdominal ultrasound showed ascites in 16 patients, hepatomegaly in 1, splenomegaly in two cases, hepatosplenomegaly in five cases, and cirrhosis in two. MRI showed signal abnormalities in 11 patients. Therapeutically, D-penicillamine was initially introduced in 18 patients and zinc acetate in 6 patients. The evolution was favorable for 15 patients still followed up in the department. Three patients died of hepatocellular failure, and two died of hepatic encephalopathy. Four patients were lost to follow-up.

A study of linear measurement and clinical correlation of brain atrophy in Wilson's disease

Background

The aim of this study was to explore the clinical relevance of linear measures of Wilson's disease (WD).

Methods

Relative values of brain atrophy in 30 patients with WD and 30 healthy volunteers were measured and compared using a manual measurement method. Linear measurement indicators of brain atrophy in patients with and without mental disorders were also compared. In addition, correlations of patients' age, disease duration, and Unified Wilson's Disease Rating Scale (UWDRS) scores with brain atrophy indicators were determined.

Results

The results showed that the e-value, Huckman number, Evans index, and lateral ventricular body index were higher in the WD group compared with the control group. The age of patients with WD was negatively correlated with the k-value and significantly positively correlated with the brainstem index. WD duration was prominently positively correlated with the d-value and negatively correlated with the j-value. In addition, neurological function scores were significantly positively correlated with the c-value, e-value, caudate nucleus index, Huckman number, Evans index, and lateral ventricular body index. By contrast, patients with psychiatric symptoms had a higher a-value and fourth ventricular index than those without psychiatric symptoms.

Conclusion

Therefore, it can be concluded that patients with WD and those with psychiatric symptoms have more severe brain atrophy compared to normal subjects. The patient's age, disease duration, and neurological function scores were positively correlated with the severity of brain atrophy.

1H-NMR-based metabolomic study of striatal injury in rats with copper-loaded Wilson's disease by Chinese and Western medicine intervention

OBJECTIVE

To investigate the metabolic mechanisms of Chinese and Western medicines on the metabolic network of striatal injury in a copper-loaded rat model of Wilson disease (WD) from a metabolomic perspective.

METHODS

We divided 60 rats into 4 groups of 15 rats each according to a random number table, namely the control group, the model group, the Bushen Huoxue Huazhuo Recipe group, and the penicillamine group, and subsequently replicated the WD copper-loaded rat model according to the literature method for a total of 12 weeks. From the 7th week onwards, each intervention group was given an equivalent dose of the corresponding drug, and the control and model groups were given an equal volume of saline gavage until the end of the model replication. We used ¹H NMR metabolomics techniques combined with multivariate statistical methods to describe the changes in the striatal metabolic profile of nerve injury in Wilson's disease and to analyze the effect of different treatments on their biomarker interventions.

RESULTS

Nerve cell damage was evident in the WD copper-loaded rat model and could be reduced to varying degrees by different methods of intervention in the striatal nerve cells. The content of glycine, serine metabolism, and valine metabolism decreased in WD copper-loaded rat model; aspartate content increased after penicillamine intervention; glycolytic metabolism, valine metabolism, taurine metabolism, and tyrosine metabolism increased in the group of Bushen Huoxue Huazhuo Recipe.

CONCLUSION

Different intervention methods of Chinese and Western medicine affect aspartate, glycolysis, taurine, tyrosine, valine, and carbon metabolism in striatal tissues of WD copper-loaded rats, and can regulate the metabolism of small molecules, which in turn have certain repairing effects on nerve damage in WD copper-loaded rats.

Construction of diagnostic prediction model for Wilson's disease

Background

Wilson's disease, also known as hepatolenticular degeneration, is a rare human autosomal recessive inherited disorder of copper metabolism. The clinical manifestations are diverse, and the diagnosis and treatment are often delayed. The purpose of this study is to establish a new predictive diagnostic model of Wilson's disease and evaluate its predictive efficacy by multivariate regression analysis of small trauma, good accuracy, low cost, and quantifiable serological indicators, in order to identify Wilson's disease early, improve the diagnosis rate, and clarify the treatment plan.

Methods

A retrospective analysis was performed on 127 patients with Wilson's disease admitted to the First People's Hospital of Yunnan Province from January 2003 to May 2022 as the experimental group and 73 patients with normal serological indicators who were not diagnosed with Wilson's disease. SPSS version 26.0 software was used for single factor screening and a multivariate binary logistic regression analysis to screen out independent factors. R version 4.1.0 software was used to establish an intuitive nomogram prediction model for the independent influencing factors included. The accuracy of the nomogram prediction model was evaluated and quantified by calculating the concordance index (C-index) and drawing the calibration curve. At the same time, the area under the curve (AUC) of the nomogram prediction model and the receiver operating characteristic (ROC) curve of the Leipzig score was calculated to compare the predictive ability of the nomogram model and the current Leipzig score for Wilson's disease.

Results

Alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (AKP), albumin (ALB), uric acid (UA), serum calcium (Ca), serum phosphorus (P), and hemoglobin (HGB) are closely related to the occurrence of Wilson's disease (p < 0.1). The prediction model of Wilson's disease contains seven independent predictors: ALT, AST, AKP, ALB, UA, Ca, and P. The AUC value of the prediction model was 0.971, and the C-index value was 0.972. The calibration curve was well fitted with the ideal curve. The nomogram prediction model had a good predictive effect on the occurrence of Wilson's disease; the ROC curve of Leipzig score was drawn, and the AUC value was calculated. The AUC of the Leipzig score was 0.969, indicating that the prediction model and the scoring system had predictive value, and the nomogram prediction model had a better predictive effect on the research objects of the center.

Conclusion

ALT, AST, AKP, ALB, UA, Ca, and P are independent predictors of Wilson's disease, and can be used as early predictors. Based on the nomogram prediction model, the optimal threshold was determined to be 0.698, which was an important reference index for judging Wilson's disease. Compared with the Leipzig score, the nomogram prediction model has a relatively high sensitivity and specificity and has a good clinical application value.

First report of Wilson disease and Bruton agammaglobulinemia in the same patient caused by new mutations in ATP7B and BTK genes

INTRODUCTION

Wilson disease is characterized by an alteration in copper metabolism that causes its accumulation in different tissues. Its diagnosis is established by the combination of clinical manifestations and paraclinical and genetic studies. Bruton agammaglobulinemia is an X-linked recessive hereditary disease belonging to the group of primary immunodeficiencies and is produced by mutation in the Bruton tyrosine kinase (BTK) gene.

CASE REPORT

A 14-year-old Colombian patient with clinical characteristics of Bruton agammaglobulinemia presented with liver disease and clinically and molecularly diagnosed with Wilson disease.

DISCUSSION

Bruton agammaglobulinemia and Wilson disease are considered rare diseases because of their low prevalence. We report for the first time a pediatric patient from southwestern Colombia presenting with both entities, and diagnosed clinically and molecularly, an association so far not reported in the literature.

A Patient with Corticobasal Syndrome and Progressive Non-Fluent Aphasia (CBS-PNFA), with Variants in ATP7B, SETX, SORL1, and FOXP1 Genes

Our aim was to analyze the phenotypic-genetic correlations in a patient diagnosed with early onset corticobasal syndrome with progressive non-fluent aphasia (CBS-PNFA), characterized by predominant apraxia of speech, accompanied by prominent right-sided upper-limb limb-kinetic apraxia, alien limb phenomenon, synkinesis, myoclonus, mild cortical sensory loss, and right-sided hemispatial neglect. Whole-exome sequencing (WES) identified rare single heterozygous variants in ATP7B (c.3207C>A), SORL1 (c.352G>A), SETX (c.2385_2387delAAA), and FOXP1 (c.1762G>A) genes. The functional analysis revealed that the deletion in the SETX gene changed the splicing pattern, which was accompanied by lower SETX mRNA levels in the patient's fibroblasts, suggesting loss-of-function as the underlying mechanism. In addition, the patient's fibroblasts demonstrated altered mitochondrial architecture with decreased connectivity, compared to the control individuals. This is the first association of the CBS-PNFA phenotype with the most common ATP7B pathogenic variant p.H1069Q, previously linked to Wilson's disease, and early onset Parkinson's disease. This study expands the complex clinical spectrum related to variants in well-known disease genes, such as ATP7B, SORL1, SETX, and FOXP1, corroborating the hypothesis of oligogenic inheritance. To date, the FOXP1 gene has been linked exclusively to neurodevelopmental speech disorders, while our study highlights its possible relevance for adult-onset progressive apraxia of speech, which guarantees further study.

Effects of High-Frequency Repetitive Transcranial Magnetic Stimulation on Upper Limb Dystonia in Patients With Wilson's Disease: A Randomized Controlled Trial

Background: Upper limb dystonia is a frequent complication of Wilson's disease (WD). It can lead to poor quality of life and disability. Currently, no effective treatment for it exists. Therefore, we carried out a clinical trial to determine whether high frequency repetitive transcranial magnetic stimulation (rTMS) on the primary motor cortex alleviates upper limb dystonia in WD patients.

Methods: This study was a single-center, double-blind, randomized clinical study, included 60 WD patients with upper limb dystonia from a research base of WD in Hefei, China. Participants were randomly divided into a treatment group (TG) and a control group (CG). The TG received rTMS at 10 Hz, while the CG received sham stimulation for 7 consecutive days. Participants were assessed at baseline, after the seventh treatment session, and at 2 and 4 weeks after the seventh treatment session. The primary outcomes included patients' objective muscle tension and stiffness as measured with the MyotonPRO device. The secondary results were scores on clinical scales assessing muscle spasm and motor symptoms, which included the Modified Ashworth Scale (MAS), Unified Wilson's Disease Rating Scale (UWDRS), Burke Fahn Marsden Scale (BFM), and the Activities of Daily Living (ADL) scale.

Results: The analysis revealed that after 10 Hz rTMS, muscle tension (P < 0.01) and stiffness (P < 0.01) as measured by the MyotonPRO device decreased significantly in the TG compared to the CG. Moreover, clinically relevant scale scores, including the MAS (P < 0.01), UWDRS (P < 0.01), BFM (P < 0.01), and ADL (P < 0.01) were also significantly reduced.

Conclusion: High-frequency rTMS over the primary motor cortex may be an effective complementary and alternative therapy to alleviating upper limb dystonia in WD patients.

Clinical Trial Registration:http://www.chictr.org.cn/, identifier: ChiCTR2100046258.

A Review of Neuroimaging in Rare Neurodegenerative Diseases

PURPOSE

Due to the variety of clinical symptoms that occur in rare neurodegenerative diseases and difficulties in the correct diagnosis, there is a need to learn their characteristic imaging findings by using conventional MRI. That knowledge helps to determine the appropriate differential diagnosis and avoid misdiagnosis. The aim of this review is to present the typical neuroimaging signs of the selected neurodegenerative disorders and to create a practical approach to imaging findings useful in everyday clinical practice. Images: Images of progressive supranuclear palsy (PSP), multiple system atrophy (MSA), corticobasal degeneration (CBD), Creutzfeldt-Jakob disease (CJD), Wilson's disease (WD), and cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) are provided to visualize and distinguish the typical features of those diseases and therefore to assist neurologists and neuroradiologists in decision-making process.

CONCLUSIONS

It is important to know the characteristic MRI features of rare neurodegenerative diseases and to use them in everyday clinical practice. MRI is a valuable tool when considering the initial diagnosis because it is proven to be very useful in the differentiation of more advanced stages of the rare neurodegenerative diseases but also from other neurodegenerative disorders.

Neurological features and outcomes of Wilson's disease: a single-center experience

Wilson's disease (WD) is an autosomal recessive genetic disorder of copper metabolism, and WD patients can present with neurologic symptoms. We aimed to report the general characteristics and prognosis of a Turkish series of WD patients with neurological manifestations. A total of 12,352 patients were screened from the patient database, and 53 WD patients were included. Patients were classified based on the predominant neurological syndrome type including tremor, dystonia, parkinsonism, or discrete neurological signs and were classified as having "good outcome," "stable," and "poor outcome" according to their treatment response. There were 32 male and 21 female patients, aged 20-66 years. The mean follow-up was 11.3 ± 4.56 years. Sixty-two percent of patients presented predominantly with neurological symptoms. Neurological WD diagnosis was established after a mean time delay of 2.3 years from the WD diagnosis. The most common neurological manifestation was dystonia, followed by tremor and parkinsonism. Fifteen patients had a family history of WD. Consanguinity was present in 20 patients. Patients were treated with D-penicillamine, trientine, zinc salts, or their combinations. Besides the main treatments, 41 patients were on symptomatic treatment for neurologic symptoms. Thirty-six patients had a "good outcome," five patients were stable, and six patients had "poor outcome." Post-chelation neurological worsening was observed in 11 patients. WD should be considered in differential diagnosis in any patient with unexplained neurologic symptoms. Early diagnosis is important, and appropriate treatment should be promptly initiated to prevent progressive and irreversible damage, with good prognosis and stable disease in the majority of the patients with treatment compliance.

Co-occurring Wilson's disease and non-penicillamine-induced systematic lupus erythematosus: a case report and literature review

Although lupus induced by penicillamine, the first-line medication for Wilson's disease, is well-documented, primary systematic lupus erythematosus (SLE) co-occurring with Wilson's disease has only rarely been reported. Symptom overlap can add to difficulties in making the correct and complete diagnosis of these two systemic diseases. An 18-year-old female was diagnosed with simultaneous Wilson's disease and SLE and was successfully treated with hydroxychloroquine and oral zinc. We also reviewed the literature for cases of Wilson's disease co-occurring with SLE not induced by penicillamine and found six other cases. Clinical presentations, diagnoses, treatments, and outcomes were analyzed and summarized to expand our understanding of this rare condition. The most frequent diagnostic clues to Wilson's disease in patients with SLE included unexplained liver damage despite well-controlled SLE, extrapyramidal symptoms and signs, hyper-intense signals of the basal ganglia bilaterally on T2-weighted and fluid-attenuated inversion recovery (FLAIR) MRI images, and Kayser-Fleischer (K-F) rings on physical examination. Penicillamine should be avoided or used cautiously in Wilson's disease patients complicated by SLE. The overall prognosis is good if treated in a timely manner. Key Points • SLE complicated by Wilson's disease or the co-occurrence of the two conditions in the absence of penicillamine may exist in rare conditions. • The diagnostic clues for identifying Wilson's disease in SLE patients may include unexplained liver damage despite well-controlled SLE, extrapyramidal symptoms and signs, and K-F rings found by physical examination. • Penicillamine should be avoided or used cautiously in Wilson's patients with SLE.

A novel deep intronic variant in ATP7B in five unrelated families affected by Wilson disease

BACKGROUND

Wilson disease is an autosomal recessive metabolic disorder resulting from accumulation of excess copper especially in the liver and brain. This disease is mainly characterized by hepatic disorders and less frequently by neuro-psychiatric disturbances. This recessive disease is due to mutation in ATP7B, which codes for an ATPase involved in copper-transport across the plasma membrane. Molecular diagnosis of WD is positive in approximately 98% of cases. Also, in few cases, WD patients present a single deleterious mutation (heterozygous) or no mutation after sanger and NGS standard sequencing analysis of ATP7B. Therefore, in these problematic WD cases, we hypothesized that deleterious mutations reside in intronic regions of ATP7B.

METHODS

Complete ATP7B gene was sequenced by Next Generation Sequencing including its promoter.

RESULTS

Five unrelated families with Wilson disease shared the same novel, deep intronic NG_008806.1 (ATP7B_v001):c.2866-1521G>A variant in ATP7B. Analysis of RNA transcripts from primary fibroblasts of one patient confirmed the deleterious impact of the intronic variant on splicing and its likely pathologic effect in this compound heterozygote.

CONCLUSION

This discovery of a novel intronic mutation in ATP7B has improved the molecular diagnosis of WD in the French patient cohort to greater than 98%. Thus, we recommend complete sequencing of ATP7B gene, including introns, as a molecular diagnostic approach in cases of clinically confirmed WD which lack pathogenic exon or promoter variants in one or both alleles.

Movement Disorders and Renal Diseases

Movement disorders often emerge from the interplay of complex pathophysiological processes involving the kidneys and the nervous system. Tremor, myoclonus, ataxia, chorea, and parkinsonism can occur in the context of renal dysfunction (azotemia and electrolyte abnormalities) or they can be part of complications of its management (dialysis and renal transplantation). On the other hand, myoglobinuria from rhabdomyolysis in status dystonicus and certain drugs used in the management of movement disorders can cause nephrotoxicity. Distinct from these well-recognized associations, it is important to appreciate that there are several inherited and acquired disorders in which movement abnormalities do not occur as a consequence of renal dysfunction or vice versa but are manifestations of common pathophysiological processes affecting the nervous system and the kidneys. These disorders are the emphasis of this review. Increasing awareness of these conditions among neurologists may help them to identify renal involvement earlier, take timely intervention by anticipating complications and focus on therapies targeting common mechanisms in addition to symptomatic management of movement disorders. Recognition of renal impairment in a patient with complex neurological presentation may narrow down the differentials and aid in reaching a definite diagnosis.

Efficacy of neuromuscular electrical stimulation on Wilson's disease patients with dysphagia

[Purpose] Dysphagia is a neurological symptom that is observed in more than half of patients with Wilson’s disease. It is often associated with aspiration pneumonia, dehydration, and malnutrition, resulting in drastic reduction of the quality of life. Neuromuscular electrical stimulation could be an adjunct therapy for dysphagia treatment. However, there is limited data about the application of NMES for dysphagia in Wilson’s disease. Thus, we explored the potential application of NMES for dysphagia treatment in Wilson’s disease. [Participants and Methods] Sixty Wilson’s disease patients who suffered from dysphagia were randomized into two groups. Swallowing function training was taught to the control group (n=30) while Neuromuscular electrical stimulation therapy was given to treatment group (n=30). Eight weeks post treatment, using the water swallow test and the Standardized Swallowing Assessment, the swallowing function was determined. [Results] None of the patients experienced discomfort before, during or after the intervention. After 8 weeks of therapy, when compared to the control, an increased improvement in swallowing function was noted for the treatment group. [Conclusion] Neuromuscular electrical stimulation treatment can improve swallowing function in Wilson’s disease patients afflicted with dysphagia. Therefore, it has the potential to be a form of therapy in clinical practice.

Wilson disease associated with immune thrombocytopenia: A case report and review of the literature

BACKGROUND

Wilson disease (WD) is a genetic disorder of hepatic copper excretion, leading to copper accumulation in various tissues. The manifestations are quite variable, and hemolytic anemia is the most common hematological presentation. WD associated with thrombocytopenia is very rare.

CASE SUMMARY

We report the case of an 11-year-old Chinese girl with WD that was associated with immune thrombocytopenia (ITP). Thrombocytopenia was the initial chief complaint for her to visit a hematologist, and ITP was diagnosed based on the results of a bone marrow biopsy and positive antiplatelet autoantibodies. About two weeks before the thrombocytopenia was found, the patient developed drooling. Tremors developed in her right hand about one week after being diagnosed with ITP, after which she was admitted to our hospital. Further evaluations were performed. Ceruloplasmin was decreased, with an increased level of copper in her 24-h urine excretion. Kayser Fleischer's ring (K-F ring) was positive. The ultrasound showed liver cirrhosis, and brain magnetic resonance imaging showed that the lenticular nucleus, caudate nucleus, and brainstem presented a low signal intensity in T1-weighted images and high signal intensity in T2-weighted images. WD was diagnosed and a genetic analysis was performed. A compound heterozygous mutation in ATP7B was detected; c.2333G>T (p.Arg778Leu) in exon 8 and c.3809A>G (p.Asn1270Ser) in exon 18. The former was inherited from her father and the latter from her mother. However, her parents showed normal liver function and negative K-F rings. Such a compound mutation in a case of WD associated with ITP in children has not been published previously.

CONCLUSION

WD can associate with thrombocytopenia but the mechanism is still unclear. We recommend that antiplatelet autoantibodies should be tested in WD patients with thrombocytopenia in future to verify the association.

Biochemical Markers for the Diagnosis and Monitoring of Wilson Disease

Wilson disease (WD) is an autosomal recessively-inherited disorder of copper metabolism and characterised by a pathological accumulation of copper. The ATP7B gene encodes for a transmembrane copper transporter essential for biliary copper excretion. Depending on time of diagnosis, severity of disease can vary widely. Almost all patients show evidence of progressive liver disease. Neurological impairments or psychiatric symptoms are common in WD patients not diagnosed during adolescence. WD is a treatable disorder, and early treatment can prevent the development of symptoms in patients diagnosed while still asymptomatic. This is why the early diagnosis of WD is crucial. The diagnosis is based on clinical symptoms, abnormal measures of copper metabolism and DNA analysis. Available treatment includes chelators and zinc salts which increase copper excretion and reduce copper uptake. In severe cases, liver transplantation is indicated and accomplishes a phenotypic correction of the hepatic gene defect. Recently, clinical development of the new copper modulating agent tetrathiomolybdate has started and direct genetic therapies are being tested in animal models. The following review focuses especially on biochemical markers and how they can be utilised in diagnosis and drug monitoring.

Genetics of Movement Disorders and the Practicing Clinician; Who and What to Test for?

PURPOSE OF REVIEW

This review aims to provide the basic knowledge on the genetics of hypokinetic and hyperkinetic movement disorders to guide clinicians in the decision of "who and what to test for?"

RECENT FINDINGS

In recent years, the identification of various genetic causes of hypokinetic and hyperkinetic movement disorders has had a great impact on a better definition of different clinical syndromes. Indeed, the advent of next-generation sequencing (NGS) techniques has provided an impressive step forward in the easy identification of genetic forms. However, this increased availability of genetic testing has challenges, including the ethical issue of genetic testing in unaffected family members, "commercially" available home testing kits and the increasing number and relevance of "variants of unknown significance." The emergent role of genetic factors has important implications on clinical practice and counseling. As a consequence, it is fundamental that practicing neurologists have a proper knowledge of the genetic background of the diseases and perform an accurate selection of who has to be tested and for which gene mutations.