Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026827 (hypotonia)
 5,860 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We studied two children who developed normally for the first 3-4 months of life and then displayed a failure-to-thrive syndrome, regression in psychomotor development, pronounced muscular hypotonia, and liver damage. At the age of about 1-2 years, optic atrophy and spastic parapareses were evident. One child died at the age of 2.5 years the other at an age of 4 years. Both children excreted 3-methylglutaconic acid, 0.1-0.4 mol/mol creatinine and 3-methylglutaric acid, 0.02-0.05 mol/mol creatinine. The excretion of 3-hydroxy-3-methylglutaric acid was not increased. One of the children was available for further biochemical studies. The activity of hydroxymethylglutaryl-CoA lyase (EC 4.1.3.4) was moderately reduced in leucocytes and fibroblasts. During a 21-h fast there was a normal formation of ketone bodies and we conclude that the cause of the syndrome is not a deficiency of hydroxymethylglutaryl-CoA lyase. Normal formation of 14CO2 from [1-14C]isovaleric acid and [2-14C]leucine in fibroblasts and leucocytes apparently excludes a deficiency of methylglutaconyl CoA-hydratase (EC 4.2.1.18).
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PMID:3-Methylglutaconic aciduria in two infants. 619 9

Deficiency of mitochondrial 3-hydroxy-3-methylglutaryl CoA lyase (HL, EC4.1.3.4.) is an autosomal recessive genetic disorder characterized by acute episodes of vomiting, hypotonia, and lethargy in the neonatal period or in infancy. Except in Saudi Arabia, where HL deficiency is the most common organic acidemia, the disorder is quite rare with only 41 cases being reported in the English literature, and only five known cases among Japanese. In this study, we present the results of a molecular analysis of all five Japanese patients together with their clinical phenotypes. Five different mutations in the HL gene were identified: one large deletion, one nonsense mutation, one missense mutation, and two splice mutations. Except for G835A (E279K) with its relatively common occurrence among Japanese, these mutations were unique to each family. The results of expression studies with mutated HL cDNAs confirmed the pathogenicity of these mutations and supported the importance of previously identified functional domains of the HL molecule, i.e., the putative catalytic site or dimerization site. In addition, we identified an alternative splicing event that resulted in the skipping of exons 5 and 6. This alternatively spliced product did not show HL activity and was present in various tissues of normal subjects. Clinically, all patients presented with similar symptoms, except that the timing of the initial presentation varied considerably, from 1 day to 1 year 3 months. In general, patients with null-activity mutations presented earlier in life, whereas those with residual activities presented later.
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PMID:Molecular and clinical analysis of Japanese patients with 3-hydroxy-3-methylglutaryl CoA lyase (HL) deficiency. 1112 31

3-Hydroxy-3-methylglutaric aciduria (OMIM 246450) is an autosomal recessive inborn error of the final step of leucine catabolic and ketogenic pathways, caused by deficiency of the enzyme 3-hydroxy-3-methylglutaryl CoA lyase (HL, HMGCL, EC 4.1.3.4). Clinically, deficiency of the enzyme results in metabolic acidosis, hyperammonemia, and infantile hypoketotic hypoglycaemia usually presenting during the first year of life with vomiting, lethargy, hypotonia, and sometimes with respiratory distress and coma. HL deficiency is relatively common in Arabic populations but seems to be rare in Europe. Our recent experience suggests that HL deficiency is the most frequent organic aciduria in the Portuguese population. We herein report on the molecular study of the HMGCL gene in 11 cases originated from the Northern area of Portugal. We detected the E37X (c.109G > T) mutation, in 84.1% of the alleles, one allele carried the V168fs(-2) (504_505delCT) and other allele the novel D204N (c.610G > A) mutation. The mutation of the last allele remained unidentified. The relatively high frequency of the "common" HMGCL Portuguese mutation makes useful the development of a rapid and specific molecular confirmation of new cases with HL deficiency in our country.
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PMID:The E37X is a common HMGCL mutation in Portuguese patients with 3-hydroxy-3-methylglutaric CoA lyase deficiency. 1530 32