Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
1996-12-17
pubmed:abstractText
Combined subtotal deficiency of C6 and C7, in which both proteins are expressed at very low levels, has been observed in homozygous form in two families. A defect at the 5' splice donor site of intron 15 of the C6 gene explains the low molecular weight of the C6 protein and is probably responsible for its low expressed concentration. The C7 defect is more enigmatic: the protein is of normal molecular weight, low circulating concentration, and altered isoelectric point. An Arg > Ser codon substitution in exon 11 is the only molecular alteration within the mature C7 protein. These defects are associated with a characteristic set of polymorphic DNA markers in the C6/C7 region, forming a distinct haplotype. The haplotype has been found in combination with a number of other haplotypes containing defective genes that lead either to C6 or C7 deficiency, but with different consequences. Where it is combined with a C6-deficient gene, the serum C7 levels can be surprisingly high, possibly because there is no C6 generating C56 to consume the C7. In contrast, where the C7 genes are both defective (but still partially functional), there may be a profound deficit of circulating C7 because there is ample C6 to produce C56 and consume the already small amount of C7. Each molecular defect has also been found in isolation and has the expected effect.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
157
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3648-57
pubmed:dateRevised
2010-8-25
pubmed:meshHeading
pubmed-meshheading:8871666-Amino Acid Sequence, pubmed-meshheading:8871666-Base Sequence, pubmed-meshheading:8871666-Chromosome Mapping, pubmed-meshheading:8871666-Complement C6, pubmed-meshheading:8871666-Complement C7, pubmed-meshheading:8871666-DNA, pubmed-meshheading:8871666-DNA Primers, pubmed-meshheading:8871666-Exons, pubmed-meshheading:8871666-Female, pubmed-meshheading:8871666-Genetic Markers, pubmed-meshheading:8871666-Haplotypes, pubmed-meshheading:8871666-Homozygote, pubmed-meshheading:8871666-Humans, pubmed-meshheading:8871666-Introns, pubmed-meshheading:8871666-Male, pubmed-meshheading:8871666-Molecular Sequence Data, pubmed-meshheading:8871666-Molecular Weight, pubmed-meshheading:8871666-Pedigree, pubmed-meshheading:8871666-Point Mutation, pubmed-meshheading:8871666-Polymerase Chain Reaction, pubmed-meshheading:8871666-Polymorphism, Genetic, pubmed-meshheading:8871666-RNA Splicing
pubmed:year
1996
pubmed:articleTitle
Molecular bases of combined subtotal deficiencies of C6 and C7: their effects in combination with other C6 and C7 deficiencies.
pubmed:affiliation
Molecular Immunopathology Unit, Medical Research Council Center, Cambridge, United Kingdom.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't