Read by QxMD icon Read

Lesch Nyhan

Evgenia Sklirou, Uta Lichter-Konecki
Phenylketonuria is a defect in phenylalanine metabolism resulting in the excretion of phenylketones and severe intellectual disability. The principle of eliminating the offending amino acid from the diet as a successful treatment strategy was demonstrated. The development of a low methionine diet to treat homocystinuria was established after identifying the transsulfuration pathway resulting in cysteine synthesis. Both conditions are examples of disorders of amino acid metabolism. Lesch-Nyhan syndrome, a rare disorder of purine metabolism resulting in intellectual disability and self-injurious behavior, is a classical inborn error of metabolism...
April 2018: Pediatric Clinics of North America
Jiao Huang, Chu Zhang, Qinxian Guo, Xianfeng Zhang, Lizhen Ma, Yuhong Zhan, Yu Chen
BACKGROUND: Lesch-Nyhan syndrome (LNS) is a congenital X-linked recessive neurogenetic disorder caused by mutations in the hypoxanthine-guanine phosphoribosyltransferase (HPRT) gene. The main clinical manifestation includes hyperuricemia, juvenile-onset gouty arthritis, and neurological developmental disorders. Studies have reported more than 400 HPRT gene mutation sites, but the incidence of LNS in the Chinese population is extremely low. METHODS: Here we report a 16-year-old male patient who suffered neurological dysfunction at an early age and gouty arthritis in his youth...
January 1, 2018: Clinical Laboratory
Maria G Zizzo, Monica Frinchi, Domenico Nuzzo, Hyder A Jinnah, Giuseppa Mudò, Daniele F Condorelli, Francesco Caciagli, Renata Ciccarelli, Patrizia Di Iorio, Flavia Mulè, Natale Belluardo, Rosa Serio
Mutations in the HGPRT1 gene, which encodes hypoxanthine-guanine phosphoribosyltransferase (HGprt), housekeeping enzyme responsible for recycling purines, lead to Lesch-Nyhan disease (LND). Clinical expression of LND indicates that HGprt deficiency has adverse effects on gastrointestinal motility. Therefore, we aimed to evaluate intestinal motility in HGprt knockout mice (HGprt¯). Spontaneous and neurally evoked mechanical activity was recorded in vitro as changes in isometric tension in circular muscle strips of distal colon...
December 20, 2017: Autonomic Neuroscience: Basic & Clinical
Adam C Cotton, R B Bell, H A Jinnah
Treatment recommendations for rare disorders often are limited by a lack of data from objective clinical trials. As a result, recommendations are often based on expert opinion. Because expert opinions sometimes conflict, many patients turn to the Internet for guidance from others who may have tried a treatment. The increasing numbers of patients and families who post opinions regarding outcomes allow for systematic data collection regarding specific treatments from the patient perspective. We used social media research methods to determine the opinions of family members or other caregivers regarding permanent removal of teeth for treatment of self-injurious biting (SIB) in patients with Lesch-Nyhan disease (LND), a particularly difficult treatment decision where expert opinion is divided...
December 15, 2017: JIMD Reports
James C Harris
PURPOSE OF REVIEW: Lesch-Nyhan Syndrome (LNS) is a metabolic disorder involving mutations in the HGPRT1 gene that result in hyperuricemia, intellectual disability, a dystonic movement disorder, and compulsive self-injury with self-mutilation. The aim of this review is to summarize recent research that documents the extended behavioral, neurologic, and neurocognitive phenotype in classic LNS, to describe milder variants of HGprt deficiency that do not self-injure and have less severe neurological and cognitive deficits, and to provide an update on treatment for associated psychiatric and behavioral disorders...
March 2018: Current Opinion in Psychiatry
Khue Vu Nguyen, Robert K Naviaux, William L Nyhan
Lesch-Nyhan disease (LND) is a rare X-linked inherited neurogenetic disorder of purine metabolism in which the enzyme, hypoxanthine-guanine phosphoribosyltransferase (HGprt) is defective. The authors report a novel point mutation that led to HGprt-related neurological dysfunction (HND) in a family in which there was a missense mutation in exon 6 of the coding region of the HPRT1 gene: g.34938G>T, c.403G>T, p.D135Y. Molecular diagnosis is consistent with the genetic heterogeneity of the HPRT1 gene responsible for HGprt deficiency...
November 2, 2017: Nucleosides, Nucleotides & Nucleic Acids
Rosa J Torres, Juan G Puig
X chromosome inactivation (XCI) ratios of normal females can range from a highly skewed ratio of 0:100 to a 50:50 ratio. In several X-linked disorders, female carriers present skewed X inactivation. Hypoxanthine-guanine phosphoribosyltransferase (HPRT) deficiency is an X-linked disorder. Males are affected and present with the complete Lesch-Nyhan disease (LND) or with a partial phenotype (Lesch-Nyhan variant, LNV). Female carriers are usually asymptomatic. The aim of the present study was to analyze the XCI pattern of HPRT-deficiency carrier females...
December 2017: Journal of Human Genetics
Eresha Jasinge, Grace Angeline Malarnangai Kularatnam, Hewa Warawitage Dilanthi, Dinesha Maduri Vidanapathirana, Kandana Liyanage Subhashinie Priyadarshika Kapilani Menike Jayasena, Nambage Dona Priyani Dhammika Chandrasiri, Neluwa Liyanage Ruwan Indika, Pyara Dilani Ratnayake, Vindya Nandani Gunasekara, Lynette Dianne Fairbanks, Blanka Stiburkova
BACKGROUND: Uric acid is the metabolic end product of purine metabolism in humans. Altered serum and urine uric acid level (both above and below the reference ranges) is an indispensable marker in detecting rare inborn errors of metabolism. We describe different case scenarios of 4 Sri Lankan patients related to abnormal uric acid levels in blood and urine. CASE 1: A one-and-half-year-old boy was investigated for haematuria and a calculus in the bladder. Xanthine crystals were seen in microscopic examination of urine sediment...
September 6, 2017: BMC Research Notes
R J Torres, S Puente, A Menendez, N Fernandez-Garcia
Complete deficiency of hypoxanthine-guanine phosphoribosyltransferase (HPRT) activity causes Lesch Nyhan disease (LND), characterized by hyperuricemia, severe action dystonia, choreoathetosis, ballismus, cognitive and attention deficit and self-injurious behavior. Partial HPRT deficiency is present in patients with Lesch-Nyhan variant (LNV), who present with HPRT-related gout and a variable degree of neurological involvement. The diagnosis of HPRT deficiency relies on clinical, biochemical, enzymatic and molecular data...
September 2017: Clinica Chimica Acta; International Journal of Clinical Chemistry
Hannah Muniz Castro, John Alvarez, Robert G Bota, Marc Yonkers, Jeremiah Tao
Attempted and completed self-enucleation, or removal of one's own eyes, is a rare but devastating form of self-mutilation behavior. It is often associated with psychiatric disorders, particularly schizophrenia, substance induced psychosis, and bipolar disorder. We report a case of a patient with a history of bipolar disorder who gouged his eyes bilaterally as an attempt to self-enucleate himself. On presentation, the patient was manic with both psychotic features of hyperreligous delusions and command auditory hallucinations of God telling him to take his eyes out...
March 22, 2017: Mental Illness
Molly Gasperini, Gregory M Findlay, Aaron McKenna, Jennifer H Milbank, Choli Lee, Melissa D Zhang, Darren A Cusanovich, Jay Shendure
The extent to which non-coding mutations contribute to Mendelian disease is a major unknown in human genetics. Relatedly, the vast majority of candidate regulatory elements have yet to be functionally validated. Here, we describe a CRISPR-based system that uses pairs of guide RNAs (gRNAs) to program thousands of kilobase-scale deletions that deeply scan across a targeted region in a tiling fashion ("ScanDel"). We applied ScanDel to HPRT1, the housekeeping gene underlying Lesch-Nyhan syndrome, an X-linked recessive disorder...
August 3, 2017: American Journal of Human Genetics
Helena Biasibetti-Brendler, Felipe Schmitz, Paula Pierozan, Bruna S Zanotto, Caroline A Prezzi, Rodrigo Binkowski de Andrade, Clovis M D Wannmacher, Angela T S Wyse
Hypoxanthine is the major purine involved in the salvage pathway of purines in the brain. High levels of hypoxanthine are characteristic of Lesch-Nyhan Disease. Since hypoxanthine is a purine closely related to ATP formation, the aim of this study was to investigate the effect of intrastriatal hypoxanthine administration on neuroenergetic parameters (pyruvate kinase, succinate dehydrogenase, complex II, cytochrome c oxidase, and ATP levels) and mitochondrial function (mitochondrial mass and membrane potential) in striatum of rats...
June 7, 2017: Molecular Neurobiology
Khue Vu Nguyen, Sebastian Silva, Monica Troncoso, Robert K Naviaux, William L Nyhan
Lesch-Nyhan disease (LND) is a rare X-linked inherited neurogenetic disorder of purine metabolism in which the enzyme, hypoxanthine-guanine phosphoribosyltransferase (HGprt) is defective. The authors report two independent point mutations leading to splicing errors: IVS 2 +1G>A, c.134 +1G>A, and IVS 3 +1G>A, c.318 +1G>A in the hypoxanthine-phosphoribosyltransferase1 (HPRT1) gene which result in exclusion of exon 2 and exon 3 respectively, in the HGprt enzyme protein from different members of two Chiloé Island families...
July 3, 2017: Nucleosides, Nucleotides & Nucleic Acids
Luca Ronda, Marialaura Marchetti, Riccardo Piano, Anastasia Liuzzi, Romina Corsini, Riccardo Percudani, Stefano Bettati
PURPOSE: Because of the evolutionary loss of the uricolytic pathway, humans accumulate poorly soluble urate as the final product of purine catabolism. Restoration of uricolysis through enzyme therapy is a promising treatment for severe hyperuricemia caused by deficiency of hypoxanthine-guanine phosphoribosyltransferase (HPRT). To this end, we studied the effect of PEG conjugation on the activity and stability of the enzymatic complement required for conversion of urate into the more soluble (S)-allantoin...
July 2017: Pharmaceutical Research
Nitesh Tewari, Vijay Prakash Mathur, Divesh Sardana, Kalpana Bansal
Lesch-Nyhan syndrome (LNS) is an X-linked recessive disorder of purine metabolism caused by a mutation in Xq26.2-q26.3 (OMIM 308000.0004). The presence of the diagnostic triad, i.e. signs of self-injurious behavior (SIB) and results of pedigree analysis and novel molecular biology & genetic testing, confirms the diagnosis of LNS. With a level of hypoxanthine guanine phosphoribosyl-transferase 1 (HPRT1) enzyme activity < 2%, patients develop neurological, neurocognitive, and neuromotor symptoms along with SIB...
February 2017: Intractable & Rare Diseases Research
Cristina Zennaro, Federica Tonon, Paola Zarattini, Milan Clai, Alessandro Corbelli, Michele Carraro, Marialaura Marchetti, Luca Ronda, Gianluca Paredi, Maria Pia Rastaldi, Riccardo Percudani
Excess of uric acid is mainly treated with xanthine oxidase (XO) inhibitors, also called uricostatics because they block the conversion of hypoxanthine and xanthine into urate. Normally, accumulation of upstream metabolites is prevented by the hypoxanthine-guanine phosphoribosyltransferase (HPRT) enzyme. The recycling pathway, however, is impaired in the presence of HPRT deficiency, as observed in Lesch-Nyhan disease. To gain insights into the consequences of purine accumulation with HPRT deficiency, we investigated the effects of the XO inhibitor allopurinol in Hprt-lacking (HPRT-/-) mice...
2017: PloS One
Khue Vu Nguyen, William L Nyhan
The present work is the development of a simple and specific kinetic method based on RT-PCR technique coupled with direct sequencing for quantification of various amyloid precursor protein-mRNA isoforms (APP-mRNA isoforms) in biological samples, especially for identifying the most abundant one that may decisive for the normal status or disease risk. Application of this kinetic method to the Lesch-Nyhan disease (LND) was performed and results indicated an epistasis between mutated hypoxanthine phosphoribosyltransferase1 (HPRT1) and APP genes...
March 16, 2017: Neuroscience Letters
Khue Vu Nguyen, Robert K Naviaux, William L Nyhan
Lesch-Nyhan disease (LND) is a rare X-linked inherited neurogenetic disorder of purine metabolism in which the enzyme, hypoxanthine-guanine phosphoribosyltransferase (HGprt) is defective. The authors report three novel independent mutations in the coding region of the HPRT1 gene from genomic DNA of (a) a carrier sister of two male patients with LND: c.569G>C, p.G190A in exon 8; and (b) two LND affected male patients unrelated to her who had two mutations: c.648delC, p.Y216X, and c.653C>G, p.A218G in exon 9...
February 2017: Nucleosides, Nucleotides & Nucleic Acids
Giulia Mori, Riccardo Percudani
In the last fifteen years, genomics and other -omics sciences have revolutionized our understanding of biological processes at the molecular level. An illustrative example is urate metabolism. Before the publication of the complete human genome, in 2003 it was believed that a single enzyme (urate oxidase) was responsible for uricolysis that is the conversion of urate into the more soluble allantoin. Now we know with great detail that this process requires the consecutive action of three enzymes that have been lost by gene inactivation in our hominoid ancestor...
2016: Giornale Italiano di Nefrologia: Organo Ufficiale Della Società Italiana di Nefrologia
Scott Bell, Ilaria Kolobova, Liam Crapper, Carl Ernst
Lesch-Nyhan syndrome (LNS) is a rare X-linked disorder caused by mutations in HPRT1, an important enzyme in the purine salvage pathway. Symptoms of LNS include dystonia, gout, intellectual disability, and self-mutilation. Despite having been characterized over 50 years ago, it remains unclear precisely how deficits in hypoxanthine and guanine recycling can lead to such a profound neurological phenotype. Several studies have proposed different hypotheses regarding the etiology of this disease, and several treatments have been tried in patients, though none have led to a satisfactory explanation of the disease...
November 2016: Molecular Syndromology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"