Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2003-5-21
pubmed:abstractText
We report the modulating action of the L436F new polymorphism identified in the GLB1 gene of a patient affected by GM1 gangliosidosis with onset at 17 months and rapidly progressive psychomotor deterioration. Sequencing analysis and familial restriction studies revealed that the maternal allele of this patient carried the L436F polymorphism in cis with the known R201C mutation. The new mutation R68W was identified in his paternal allele. Since the GLB1 activity of the patient's leukocytes was very low and compatible with both the type-I and the type-II form of the disease, the potential impact of each mutation was investigated by expression studies in COS1 cells, and Western blots. Expression study of the R68W mutated allele resulted in no GLB1 activity. Transfection with a vector carrying the R201C mutation gave rise to a residual GLB1 activity, which, interestingly, was severely reduced in transfection with the L436F/R201C allele. These expression studies, together with co-transfection experiments, suggest that the R201C/L436F GLB1 "complex allele" leads to this patient's clinical and biochemical findings. The type-II phenotype of the disease is subdivided into late infantile and juvenile forms. The clinical and molecular characterization of this patient as late-infantile GM1 gangliosidosis is in keeping with a clear-cut division between the two sub forms of the type-II phenotype. The modulating role of the L436F polymorphism should be stressed as a cause of this patient's condition. This model suggests that the combination of missense mutations or polymorphisms should be evaluated when diagnosing inherited genetic disorders.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0340-6717
pubmed:author
pubmed:issnType
Print
pubmed:volume
113
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
44-50
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:12644936-Alleles, pubmed-meshheading:12644936-Amino Acid Substitution, pubmed-meshheading:12644936-Animals, pubmed-meshheading:12644936-Blotting, Western, pubmed-meshheading:12644936-COS Cells, pubmed-meshheading:12644936-Cercopithecus aethiops, pubmed-meshheading:12644936-DNA Mutational Analysis, pubmed-meshheading:12644936-DNA Primers, pubmed-meshheading:12644936-Gangliosidosis, GM1, pubmed-meshheading:12644936-Humans, pubmed-meshheading:12644936-Infant, pubmed-meshheading:12644936-Leukocytes, pubmed-meshheading:12644936-Male, pubmed-meshheading:12644936-Mutagenesis, Site-Directed, pubmed-meshheading:12644936-Phenotype, pubmed-meshheading:12644936-Polymerase Chain Reaction, pubmed-meshheading:12644936-Polymorphism, Genetic, pubmed-meshheading:12644936-Transfection, pubmed-meshheading:12644936-beta-Galactosidase
pubmed:year
2003
pubmed:articleTitle
Modulating action of the new polymorphism L436F detected in the GLB1 gene of a type-II GM1 gangliosidosis patient.
pubmed:affiliation
Department of Paediatrics, University of Florence, Children's Hospital A.Meyer, Via Luca Giordano 13, 50132, Florence, Italy.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Case Reports, Research Support, Non-U.S. Gov't