BACKGROUND The combination of ataxia and hypogonadism was first described more than a century ago, but its genetic basis has remained elusive. METHODS We performed whole-exome sequencing in a patient with ataxia and hypogonadotropic hypogonadism, followed by targeted sequencing of candidate genes in similarly affected patients. Neurologic and reproductive endocrine phenotypes were characterized in detail. The effects of sequence variants and the presence of an epistatic interaction were tested in a zebrafish model. RESULTS Digenic homozygous mutations in RNF216 and OTUD4, which encode a ubiquitin E3 ligase and a deubiquitinase, respectively, were found in three affected siblings in a consanguineous family. Additional screening identified compound heterozygous truncating mutations in RNF216 in an unrelated patient and single heterozygous deleterious mutations in four other patients. Knockdown of rnf216 or otud4 in zebrafish embryos induced defects in the eye, optic tectum, and cerebellum; combinatorial suppression of both genes exacerbated these phenotypes, which were rescued by nonmutant, but not mutant, human RNF216 or OTUD4 messenger RNA. All patients had progressive ataxia and dementia. Neuronal loss was observed in cerebellar pathways and the hippocampus; surviving hippocampal neurons contained ubiquitin-immunoreactive intranuclear inclusions. Defects were detected at the hypothalamic and pituitary levels of the reproductive endocrine axis. CONCLUSIONS The syndrome of hypogonadotropic hypogonadism, ataxia, and dementia can be caused by inactivating mutations in RNF216 or by the combination of mutations in RNF216 and OTUD4. These findings link disordered ubiquitination to neurodegeneration and reproductive dysfunction and highlight the power of whole-exome sequencing in combination with functional studies to unveil genetic interactions that cause disease. (Funded by the National Institutes of Health and others.)

The aim of this review is to summarize the recent literature regarding abnormalities in sensory functioning in individuals with autism spectrum disorder (ASD), including evidence regarding the neurobiological basis of these symptoms, their clinical correlates, and their treatment. Abnormalities in responses to sensory stimuli are highly prevalent in individuals with ASD. The underlying neurobiology of these symptoms is unclear, but several theories have been proposed linking possible etiologies of sensory dysfunction with known abnormalities in brain structure and function that are associated with ASD. In addition to the distress that sensory symptoms can cause patients and caregivers, these phenomena have been correlated with several other problematic symptoms and behaviors associated with ASD, including restrictive and repetitive behavior, self-injurious behavior, anxiety, inattention, and gastrointestinal complaints. It is unclear whether these correlations are causative in nature or whether they are due to shared underlying pathophysiology. The best-known treatments for sensory symptoms in ASD involve a program of occupational therapy that is specifically tailored to the needs of the individual and that may include sensory integration therapy, a sensory diet, and environmental modifications. While some empirical evidence supports these treatments, more research is needed to evaluate their efficacy, and other means of alleviating these symptoms, including possible psychopharmacological interventions, need to be explored. Additional research into the sensory symptoms associated with ASD has the potential to shed more light on the nature and pathophysiology of these disorders and to open new avenues of effective treatments.

Objectives-This paper summarizes and evaluates recent advances in the genetics of Gilles de la Tourette Syndrome (GTS).Methods-This is a review of recent literature focusing on: 1) the genetic etiology of GTS; 2) common genetic components of GTS, Attention Deficit Hyperactivity Disorder (ADHD), and Obsessive Compulsive Disorder (OCD); 3) recent linkage studies of GTS; 4) chromosomal translocations in GTS; and 5) candidate gene studies.Results-Family, twin and segregation studies provide strong evidence for the genetic nature of GTS. GTS is a heterogeneous disorder with complex inheritance patterns and phenotypic manifestations. Family studies of GTS and OCD indicate that an early onset form of OCD is likely to share common genetic factors with GTS. While there apparently is an etiological relationship between GTS and ADHD, it appears that the common form of ADHD does not share genetic factors with GTS. The largest genome wide linkage study to date observed evidence for linkage on chromosome 2p23.2 (P=3.8 × 10 −5 ). No causative candidate genes have been identified, and recent studies suggest that the newly identified candidate gene SLITRK1 is not a major risk gene for the majority of individuals with GTS. Conclusion-The genetics of GTS are complex and not well understood. The Genome Wide Association Study (GWAS) design can hopefully overcome the limitations of linkage and candidate gene studies. However, large-scale collaborations are needed to provide enough power to utilize the GWAS design for discovery of causative mutations. Knowledge of susceptibility mutations and biological pathways involved should eventually lead to new treatment paradigms for GTS. KeywordsTourette's Disorder; Genetics; Family study; ReviewIn the original description of the syndrome that bears his name, Georges Gilles de la Tourette observed that the disorder was familial [1]. Subsequently, there has been considerable research devoted to systematically examining whether that original observation could be replicated and whether the observed familiality is due in part to genetic factors. These studies have included family studies, twin studies, genetic linkage studies and genetic association (candidate gene)Correspondence to: Dr. David L. Pauls, PNGU, 185 Cambridge Street, Massachusetts General Hospital, Boston, MA 02114; dpauls@pngu.mgh.harvard.edu; fax: (617)726-0830. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. NIH Public Access Family StudiesFamily studies have repeatedly demonstrated that Gilles de la Tourette Syndrome (GTS) is highly familial. Establishing that there is familial ag...