Joubert syndrome (JS) is a recessive disorder that is characterized by midbrain-hindbrain malformation and shows the \"molar tooth sign\" on magnetic resonance imaging. Mutations in 40 genes, including Abelson helper integration site 1 (AHI1), inositol polyphosphate-5-phosphatase (INPP5E), coiled-coil and c2 domain-containing protein 2A (CC2D2A), and ARL2-like protein 1 (ARL13B), can cause JS. Classic JS is a part of a group of diseases associated with JS, and its manifestations include various neurological signs such as skeletal abnormalities, ocular coloboma, renal disease, and hepatic fibrosis. Here, we present a proband with the molar tooth sign, ataxia, and developmental and psychomotor delays in a Dagestan family from Russia. Molecular genetic testing revealed two novel heterozygous variants, c.2924G>A (p.Arg975His) in exon 28 and c.1241C>G (p.Pro414Arg) in exon 12 of the transmembrane protein 67 (TMEM67) gene. These TMEM67 gene variants significantly affected the development of JS type 6. This case highlights the importance of whole exome sequencing for a proper clinical diagnosis of children with complex motor and psycho-language delays. This case also expands the clinical phenotype and genotype of TMEM67-associated diseases.

Joubert syndrome (JS) is a rare, autosomal recessive, genetic syndrome that derives from the defects in a sensory organelle, the primary cilia. It is a multiorgan disorder affecting the brain, kidneys, liver, and eyes. The most common presenting feature in the newborn period is hypotonia, abnormal eye movements, irregular breathing pattern, characterized by episodic hyperpnea and apnea, later on, ataxia, and developmental retardation. Besides, a range of highly variable, systemic and ocular features can be present. We report a case of 2-month-old female infant, the product of a consanguineous marriage, with a sibling affected by JS, presenting with intermittent hyperpnea, apnea, facial dysmorphism, strabismus, oculomotor apraxia, proptosis, retinal dystrophy, chorioretinal coloboma, and large retrobulbar cysts communicating with the coloboma. Magnetic resonance imaging of the brain revealed the characteristic neuroradiologic finding, the \"molar tooth sign.\" The child does not fix or follow the light, and the visual prognosis with all the ocular features of the syndrome present is extremely poor. In addition to adding to the diversity of ocular phenotypes, this case reiterates the importance of identifying the syndrome, understanding the varied ocular phenotypic presentations, need for further research on causative genes, prenatal diagnosis in affected families, interventions, and adequate genetic counseling.

UNASSIGNED: Joubert syndrome is a rare disorder, characterized by a complex midbrain malformation caused by defects in the structure and/or function of the primary cilium.
UNASSIGNED: A 15-year-old boy with mild intellectual disability, hypotonia, mild ataxia, and abnormal eye movements diagnosed as having Joubert Syndrome since childhood, was referred to the Sleep Unit because spells of apnea while sleeping. He did not complain of snoring or daytime somnolence. The macro and microstructure of sleep and the comorbidities such respiratory abnormalities, periodic legs movements (PLM) and paroxysmal motor arousals (PA) and minimal motor events (MME) are described for the first time in Joubert syndrome.
UNASSIGNED: EEG was normal. Video-polysomnography revealed a nocturnal disturbed sleep and periods of hyperpnea accompanied by body movements and followed by a periodic breathing lasting several minutes with no oxygen desaturation. The arousals provoked by apneas triggered paroxysmal motor events with dystonic movements in the hand and right foot accompanied by a spontaneous Babinski. Brain MRI showed the typical \"molar tooth sign\".
UNASSIGNED: Joubert syndrome is a heterogeneous disease. Epileptic seizures have been reported in some cases. Video-PSG is mandatory for the identification of nocturnal breathing abnormalities and sleep-related motor paroxysmal episodes.

Joubert syndrome (JS) is a rare autosomal recessive disease affecting the cilium, an intracellular organelle. It has a wide spectrum of presentations with the involvement of multiple genes. JS has multiple subtypes that are either pure JS or JS with other organ involvement such as the kidneys, liver, and others. However, all subtypes share the involvement of the cerebellar peduncles and the brainstem, which presents as \"a molar tooth sign\" on magnetic resonance imaging, hypotonia, and intellectual disability. It has a higher prevalence among children with few able to survive to adulthood. Unfortunately, survivors live with debilitating comorbidities. Here, we present the case of a 20-year-old patient who presented with a new onset of dysphagia that led to a diagnosis of JS.

Joubert syndrome is an autosomal recessive genetic disorder that was first described in 1969. It can present with neonatal respiratory distress, ocular motility abnormalities, developmental delays, and other congenital cerebellar malformations. It is also connected to autism, hydrocephalus, and duodenal atresia. The incidence and severity of the disease are variable according to different presentations. We report a case of a female infant that was born to nonconsanguineous marriage and diagnosed at the age of four months with Joubert syndrome. The patient presented with global developmental delay and abnormal bilateral eye movements. Upon further investigation, brain magnetic resonance imaging showed a molar tooth sign, which is a characteristic finding and one of the diagnostic criteria of Joubert syndrome. A multidisciplinary team approach with ophthalmology, pediatrics, and physiotherapy departments was used, and the patient showed good progress in ocular, neurological and mental development. In conclusion, Joubert syndrome can be diagnosed early with the help of magnetic imaging and a multidisciplinary approach is necessary to provide good quality of life to these patients.

Joubert syndrome is a genetically heterogeneous disorder that belongs to the group of cerebello-oculo-renal syndromes. It is characterised by neurodevelopmental abnormalities and complex midbrain-hindbrain malformation, visible on brain imaging as a molar tooth sign. It is classified as a ciliopathy and has variable renal involvement. Herein, we report a case of a 9-year-old boy with developmental delay, presented as chronic kidney disease and evaluation showed features of Joubert syndrome. Recognition of specific clinical and radiological findings will help in early diagnosis and appropriate care.

Joubert Syndrome is a rare autosomal recessive genetic disorder characterized by a distinctive midbrain-hindbrain malformation that gives the appearance of \"the molar tooth sign\" on axial magnetic resonance imaging (MRI). Mutations in the implicated genes, affect proteins integral to cellular structures like the primary cilium, basal bodies and centromeres, categorizing Joubert syndrome as a ciliopathy. The most common clinical manifestations include moderate to severe hypotonia in early infancy with ataxia developing later in life, abnormal breathing patterns (tachypnea, apnea), atypical eye movements, development delay and intellectual disabilities. Differential diagnosis between different ciliopathies is challenging due to the overlapping clinical features. French neurologist Marie Joubert was the first to describe the clinical findings in 1969 and later the disorder was named after her. In this report, we present the case of a newborn female patient who was admitted to the neonatal intensive care unit 12 hours after birth, presenting with dyspnea, cyanosis, signs of respiratory distress and seizures. During the course of her hospitalization elevated levels of urea and creatinine were detected and after an abdominal ultrasound and CT evaluation bilateral renal hyperplasia and polycystic kidney disease were discovered. An MRI of the head and neck revealed the presence of inferior vermis agenesis, with a medial crack in cerebellum, a partial dysgenesis of corpus callosum, an underlying and thicker cerebral peduncle, as well as the molar tooth sign suggesting a diagnosis of Joubert syndrome. The diagnosis was ultimately confirmed through molecular genetic testing. Through this case report, we hope to draw attention to this rare and elusive group of disorders and emphasize the value of a prompt diagnosis and a proactive and multidisciplinary approach in the management of these patients.

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Joubert syndrome (JS) is a congenital autosomal-recessive or-in rare cases-X-linked inherited disease. The diagnostic hallmark of the so-called molar tooth sign describes the morphological manifestation of the mid- and hind-brain in axial brain scans. Affected individuals show delayed development, intellectual disability, ataxia, hyperpnea, sleep apnea, abnormal eye, and tongue movements as well as hypotonia. At the cellular level, JS is associated with the compromised biogenesis of sensory cilia, which identifies JS as a member of the large group of ciliopathies. Here we report on the identification of novel compound heterozygous variants (p.Y503C and p.Q485*) in the centrosomal gene PIBF1 in a patient with JS via trio whole exome sequencing. We have studied the underlying disease mechanism in the frog Xenopus, which offers fast assessment of cilia functions in a number of embryological contexts. Morpholino oligomer (MO) mediated knockdown of the orthologous Xenopus pibf1 gene resulted in defective mucociliary clearance in the larval epidermis, due to reduced cilia numbers and motility on multiciliated cells. To functionally assess patient alleles, mutations were analyzed in the larval skin: the p.Q485* nonsense mutation resulted in a disturbed localization of PIBF1 to the ciliary base. This mutant failed to rescue the ciliation phenotype following knockdown of endogenous pibf1. In contrast, the missense variant p.Y503C resulted in attenuated rescue capacity compared to the wild type allele. Based on these results, we conclude that in the case of this patient, JS is the result of a pathogenic combination of an amorphic and a hypomorphic PIBF1 allele. Our study underscores the versatility of the Xenopus model to study ciliopathies such as JS in a rapid and cost-effective manner, which should render this animal model attractive for future studies of human ciliopathies.

Joubert syndrome is a rare inherited cerebellar ataxia with the dysgenesis of the cerebellar vermis, called the molar tooth sign. The combination of a large number of causative genes, more than 27, and the various clinical features involving multiple organs has established many genotypic-phenotypic correlations in Joubert syndrome. TMEM67 is one of the genes that are relatively well established as contributing to Joubert syndrome with liver involvement. Here, we report a 2-month-old boy who was initially treated for urinary tract infection, which further led to the diagnosis of Joubert syndrome accompanied by renal hypodysplasia with two different mutations: c.2522A>C and c.1065 + 4Adel in TMEM67.