Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.30.2 (endonuclease)
 18,621 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Inherited deficiency of ferrochelatase results in erythropoietic protoporphyria (EPP). Genetic heterogeneity at the locus for human ferrochelatase was investigated. Analysis of genomic DNA of patients with EPP and of control subjects by restriction endonuclease techniques using ten different enzymes detected polymorphisms only at sites recognized by EcoRI, HincII, PstI and TaqI. None of these polymorphisms alone was specific for expression of the disease since each was observed in control subjects as well. Three of these polymorphisms (at EcoRI, HincII and PstI sites) were always associated, indicating linkage. These and other studies demonstrate that the ferrochelatase gene is markedly heterogeneous. It is not yet clear whether some of the mutations associated with these polymorphisms contribute to expression of EPP.
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PMID:Human protoporphyria: genetic heterogeneity at the ferrochelatase locus. 765 62

A pseudogene related to the functional gene (FECH) for the heme biosynthetic enzyme ferrochelatase (ferroheme-protolyase; EC 4.99.1.1.) was isolated from a human genomic library using a ferrochelatase cDNA hybridization probe. The pseudogene shows > 80% overall nucleotide sequence identity to the functional gene (including the 3' untranslated region and polyadenylation signals) but contains no intronic sequences in the region corresponding to the open reading frame of expressed ferrochelatase. Furthermore, the pseudogene sequence contains small deletions and insertions creating frameshifts and numerous termination codons, indicating that it does not encode a functional polypeptide. Northern blot analysis using pseudogene-specific probes failed to demonstrate transcripts in samples of human erythroid cell RNA in which ferrochelatase mRNA was readily detected. Southern blot experiments using restriction endonuclease-digested human genomic DNA probed either with ferrochelatase-specific cDNA fragments or pseudogene-specific genomic sequences confirmed the presence of distinct loci for the expressed and nonfunctional genes, respectively. Localization of the human ferrochelatase pseudogene to 3p22-p23 was determined by fluorescent metaphase chromosomal hybridization in situ using three genomic clones in lambda EMBL3 spanning a contiguous region of approximately 30 kb. This newly identified locus, distinct from the expressed FECH gene, on 18q22, is characteristic of a processed human pseudogene. The existence of the ferrochelatase pseudogene has practical implications for the molecular analysis of mutations responsible for erythropoietic protoporphyria in man.
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PMID:Molecular analysis of functional and nonfunctional genes for human ferrochelatase: isolation and characterization of a FECH pseudogene and its sublocalization on chromosome 3. 803 22