Glutamate formiminotransferase deficiency (OMIM 229100) is an autosomal recessive disorder marked by clinical heterogeneity. The severe phenotype, first identified in patients of Japanese descent, includes high levels of formiminoglutamate (FIGLU) in the urine in response to histidine loading, megaloblastic anemia, and mental retardation. The mild phenotype is marked by high levels of FIGLU in the urine in the absence of histidine loading, mild developmental delay and no hematological abnormalities. The gene for human glutamate formiminotransferase-cyclodeaminase consists of 15 exons and is located at 21q22.3. The protein consists of a tetramer of dimers, with dimerization essential for both formiminotransferase and cyclodeaminase activity. / Genomic DNA extracted from cell lines from three patients with suspected glutamate formiminotransferase deficiency was analyzed by PCR and sequencing of individual exons. Cell lines WG 1758 and WG 1759 are from two siblings of Germanic descent. Both siblings are heterozygous for the mutations c457 C → T and c940 G → C. The c457 C → T changes a conserved arginine to a cysteine in a loop involved in the binding of formiminotetrahydrofolate to the enzyme. The c940 G → C mutation converts an arginine to a proline in an alpha-helix essential for the dimerization of the formiminotransferase domain. Cell line WG 1795 is from a patient of Danish descent. The patient appears to be hemizygous for a c1033 insG mutation. Quantitative PCR suggests the presence of a deletion on the other chromosome, which minimally encompasses exon 9. All of the FTCD gene changes were absent in 100 control individuals (200 alleles).
Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.33776 |
Date | January 2001 |
Creators | Hilton, John Frederick. |
Contributors | Rosenblatt, D. S. (advisor) |
Publisher | McGill University |
Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
Language | English |
Detected Language | English |
Type | Electronic Thesis or Dissertation |
Format | application/pdf |
Coverage | Master of Science (Department of Biology.) |
Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
Relation | alephsysno: 001875314, proquestno: MQ78893, Theses scanned by UMI/ProQuest. |
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