Tyrosine hydroxylase deficiency: a treatable disorder of brain catecholamine biosynthesis

Tyrosine hydroxylase deficiency is an autosomal recessive disorder resulting from cerebral catecholamine deficiency. Tyrosine hydroxylase deficiency has been reported in fewer than 40 patients worldwide. To recapitulate all available evidence on clinical phenotypes and rational diagnostic and therapeutic approaches for this devastating, but treatable, neurometabolic disorder, we studied 36 patients with tyrosine hydroxylase deficiency and reviewed the literature. Based on the presenting neurological features, tyrosine hydroxylase deficiency can be divided in two phenotypes: an infantile onset, progressive, hypokinetic-rigid syndrome with dystonia (type A), and a complex encephalopathy with neonatal onset (type B). Decreased cerebrospinal fluid concentrations of homovanillic acid and 3-methoxy-4-hydroxyphenylethylene glycol, with normal 5-hydroxyindoleacetic acid cerebrospinal fluid concentrations, are the biochemical hallmark of tyrosine hydroxylase deficiency. The homovanillic acid concentrations and homovanillic acid/5-hydroxyindoleacetic acid ratio in cerebrospinal fluid correlate with the severity of the phenotype. Tyrosine hydroxylase deficiency is almost exclusively caused by missense mutations in the TH gene and its promoter region, suggesting that mutations with more deleterious effects on the protein are incompatible with life. Genotype-phenotype correlations do not exist for the common c.698G>A and c.707T>C mutations. Carriership of at least one promotor mutation, however, apparently predicts type A tyrosine hydroxylase deficiency. Most patients with tyrosine hydroxylase deficiency can be successfully treated with l-dop

Phenotypic insights into ADCY5-associated disease

Background Adenylyl cyclase 5 (ADCY5) mutations is associated with heterogenous syndromes: familial dyskinesia and facial myokymia; paroxysmal chorea and dystonia; autosomal‐dominant chorea and dystonia; and benign hereditary chorea. We provide detailed clinical data on 7 patients from six new kindreds with mutations in the ADCY5 gene, in order to expand and define the phenotypic spectrum of ADCY5 mutations. Methods In 5 of the 7 patients, followed over a period of 9 to 32 years, ADCY5 was sequenced by Sanger sequencing. The other 2 unrelated patients participated in studies for undiagnosed pediatric hyperkinetic movement disorders and underwent whole‐exome sequencing. Results Five patients had the previously reported p.R418W ADCY5 mutation; we also identified two novel mutations at p.R418G and p.R418Q. All patients presented with motor milestone delay, infantile‐onset action‐induced generalized choreoathetosis, dystonia, or myoclonus, with episodic exacerbations during drowsiness being a characteristic feature. Axial hypotonia, impaired upward saccades, and intellectual disability were variable features. The p.R418G and p.R418Q mutation patients had a milder phenotype. Six of seven patients had mild functional gain with clonazepam or clobazam. One patient had bilateral globus pallidal DBS at the age of 33 with marked reduction in dyskinesia, which resulted in mild functional improvement. Conclusion We further delineate the clinical features of ADCY5 gene mutations and illustrate its wide phenotypic expression. We describe mild improvement after treatment with clonazepam, clobazam, and bilateral pallidal DBS. ADCY5‐associated dyskinesia may be under‐recognized, and its diagnosis has important prognostic, genetic, and therapeutic implications

Characterization of greater middle eastern genetic variation for enhanced disease gene discovery

The Greater Middle East (GME) has been a central hub of human migration and population admixture. The tradition of consanguinity, variably practiced in the Persian Gulf region, North Africa, and Central Asia1-3, has resulted in an elevated burden of recessive disease4. Here we generated a whole-exome GME variome from 1,111 unrelated subjects. We detected substantial diversity and admixture in continental and subregional populations, corresponding to several ancient founder populations with little evidence of bottlenecks. Measured consanguinity rates were an order of magnitude above those in other sampled populations, and the GME population exhibited an increased burden of runs of homozygosity (ROHs) but showed no evidence for reduced burden of deleterious variation due to classically theorized ‘genetic purging’. Applying this database to unsolved recessive conditions in the GME population reduced the number of potential disease-causing variants by four- to sevenfold. These results show variegated genetic architecture in GME populations and support future human genetic discoveries in Mendelian and population genetics

Defective p53 response and apoptosis associated with an ataxia-telangiectasia-like phenotype

Ataxia-telangiectasia mutated (ATM), the protein defective in ataxia-telangiectasia, plays a central role in DNA damage response and signaling to cell cycle checkpoints. We describe here a cell line from a patient with an ataxia-telangiectasia-like clinical phenotype defective in the p53 response to radiation but with normal ATM activation and efficient downstream phosphorylation of other ATM substrates. No mutations were detected in ATM cDNA. A normal level of interaction between p53 and peptidyl-prolyl-isomerase Pin1 suggests that posttranslational modification was intact in these cells but operating at reduced level. Defective p53 stabilization was accompanied by defective induction of p53 effector genes and failure to induce apoptosis in response to DNA-damaging agents. Continued association between p53 and murine double minute-2 (Mdm2) occurred in irradiated ATL2ABR cells in response to DNA damage, and incubation with Mdm2 antagonists, nutlins, increased the stabilization of p53 and its transcriptional activity but failed to induce apoptosis. These results suggest that ATM-dependent stabilization of p53 and induction of apoptosis by radiation involve an additional factor(s) that is defective in ATL2ABR cells

GNAO1-related movement disorder with life-threatening exacerbations: movement phenomenology and response to DBS.

GNAO1 (OMIM 139311) encodes an Gα0 CNS protein responsible for regulation of GABA-B and α2-receptors, and neurotransmitter release. Mutations of GNAO1 are reported in patients with epileptic encephalopathy (EE) at times with a movement disorder (MD); some display severe hyperkinetic movements without EE, three underwent Deep Brain Stimulation (DBS) with reduction in exacerbations.1–4 (see online supplementary table 3, supporting information (SI))

Genetic epilepsy with febrile seizures plus: refining the spectrum

Objective: Following our original description of generalized epilepsy with febrile seizures plus (GEFS1) in 1997, we analyze the phenotypic spectrum in 409 affected individuals in 60 families (31 new families) and expand the GEFS1 spectrum. Methods: We performed detailed electroclinical phenotyping on all available affected family members. Genetic analysis of known GEFS1 genes was carried out where possible. We compared our phenotypic and genetic data to those published in the literature over the last 19 years. Results: We identified new phenotypes within the GEFS1 spectrum: focal seizures without preceding febrile seizures (16/409 [4%]), classic genetic generalized epilepsies (22/409 [5%]), and afebrile generalized tonic-clonic seizures (9/409 [2%]). Febrile seizures remains the most frequent phenotype in GEFS1 (178/409 [44%]), followed by febrile seizures plus (111/409 [27%]). One third (50/163 [31%]) of GEFS1 families tested have a pathogenic variant in a known GEFS1 gene. Conclusion: As 37/409 (9%) affected individuals have focal epilepsies, we suggest that GEFS1 be renamed genetic epilepsy with febrile seizures plus rather than generalized epilepsy with febrile seizures plus. The phenotypic overlap between GEFS1 and the classic generalized epilepsies is considerably greater than first thought. The clinical and molecular data suggest that the 2 major groups of generalized epilepsies share genetic determinants.National Health and Medical Research Council of Australia [628952, 1091593, 466671, 1006110, 1104831, 1032603, 1063799]SCI(E)ARTICLE121210-12198

Sociable (social) science – crafting new relationships between research and government

The civil service represents a significant community of analysts and researchers, but their work can at times seem independent from that taking place within academia. Ben Hepworth describes how the UK’s Ministry of Justice has worked to reframe its relationship with external academics and how a more collaborative and co-productive approach has enabled the department to approach emerging challenges in innovative ways