DNase I hypersensitivity mapping and promoter polymorphism analysis of human C4

Journal Article · Sat Apr 01 04:00:00 EST 1995 · Immunogenetics

DOI:https://doi.org/10.1007/BF00163992· OSTI ID:91085

Vaishnaw, A K; Hargreaves, R; Morley, B J ^[1]

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1. Hammersmith Hospital, London (United Kingdom); and others

Human complement component C4 is encoded by two structurally distinct loci in the major histocompatibility complex (MHC) class III region. The two isotypes, C4A and C4B, differ at only four residues in the C4d fragment, but C4 constitutes the most polymorphic of the complement components. It is not known, however, whether the regions involved in the regulation of C4 expression also display polymorphic variation. By using the technique of DNase I hypersensitivity mapping, we established that the only area of transcriptional activity for C4 in the hepatocyte cell line, HepG2, occurs approximately 500 base pairs upstream of the transcriptional start site. This region was found to be remarkably constant in sequence when analyzed in the context of differing MHC haplotypes including HLA B57, C4A6, C4B1, DR7, which has been correlated with reduced expression of the C4A isotype. Similarly, polymerase chain reaction followed by single-strand conformation polymorphism analysis failed to demonstrate any promoter polymorphisms in 103 individuals comprising 52 systemic lupus erythermatosus patients and 51 healthy controls. 36 refs., 3 figs., 2 tabs.

• Sponsoring Organization: USDOE
• OSTI ID: 91085
• Journal Information: Immunogenetics, Journal Name: Immunogenetics Journal Issue: 6 Vol. 41; ISSN IMNGBK; ISSN 0093-7711
• Country of Publication: United States
• Language: English

Related Subjects

55 BIOLOGY AND MEDICINE
BASIC STUDIES
GENE MUTATIONS
GENE REPRESSORS
GENES
GENETIC MAPPING
GLYCOPROTEINS
HISTOCOMPATIBILITY COMPLEX
HUMAN CHROMOSOME 6
NUCLEOTIDES
PATIENTS
POLYMERASE CHAIN REACTION
RHEUMATIC DISEASES