Biomaterial Database

The importance of C4A null genes in Norwegian patients with systemic lupus erythematosus. 1995

S Skarsvåg

Department of Immunology and Bloodbank, Faculty of Medicine, University of Trondheim, Norway.

C4A null genes were determined by RFLP (Taq I) and SSO-probing on PCR-amplified C4-DNA in 51 Scandinavian patients with systemic lupus erythematosus (SLE) and 124 controls. Associations of the alleles DRB1*0301, DQA1*0501, DQB1*0201 had previously been found in this SLE group, as well as increased frequency of HLA-DRB1 and -DQ homozygosity. The frequency of the allele C4A*Q0 was increased among the patients (RR = 2.3, P = 0.0172). The SSO-probing revealed additional cases of C4A*Q0 homozygotes among the controls, leading to diverging RR values for C4A*Q0 homozygotes depending on the technique used. The RFLP method gave an RR of 9.7 (P = 0.0028), while the SSO-probing resulted in an RR of 4.8 (P = 0.0153), demonstrating that unprecise characterization of C4A*Q0 in a relatively small material has great effect on the calculated RR. Multiple 2 x 2 tests were performed in an attempt to detect the strongest association of the alleles DRB1*0301, DQA1*0501 and C4A*Q0 (in linkage disequilibrium). These comparisons showed a trend towards stronger association for DAQ1*0501 and DRB1*0301 than for C4A*Q0, and no interaction between the HLA alleles and the allele C4A*Q0. This may suggest that HLA class II molecules themselves and/or an unknown susceptibility gene located near the DQA1 and DRB1 loci are involved in the pathogenesis of SLE.

UI	MeSH Term	Description	Entries
D008180	Lupus Erythematosus, Systemic	A chronic, relapsing, inflammatory, and often febrile multisystemic disorder of connective tissue, characterized principally by involvement of the skin, joints, kidneys, and serosal membranes. It is of unknown etiology, but is thought to represent a failure of the regulatory mechanisms of the autoimmune system. The disease is marked by a wide range of system dysfunctions, an elevated erythrocyte sedimentation rate, and the formation of LE cells in the blood or bone marrow.	Libman-Sacks Disease,Lupus Erythematosus Disseminatus,Systemic Lupus Erythematosus,Disease, Libman-Sacks,Libman Sacks Disease
D008297	Male		Males
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D012150	Polymorphism, Restriction Fragment Length	Variation occurring within a species in the presence or length of DNA fragment generated by a specific endonuclease at a specific site in the genome. Such variations are generated by mutations that create or abolish recognition sites for these enzymes or change the length of the fragment.	RFLP,Restriction Fragment Length Polymorphism,RFLPs,Restriction Fragment Length Polymorphisms
D005260	Female		Females
D005802	Genes, MHC Class II	Genetic loci in the vertebrate major histocompatibility complex that encode polymorphic products which control the immune response to specific antigens. The genes are found in the HLA-D region in humans and include H-2M, I-A, and I-E loci in mice.	Class II Genes,Genes, Class II,Genes, HLA Class II,MHC Class II Genes,Class II Gene,Gene, Class II
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000293	Adolescent	A person 13 to 18 years of age.	Adolescence,Youth,Adolescents,Adolescents, Female,Adolescents, Male,Teenagers,Teens,Adolescent, Female,Adolescent, Male,Female Adolescent,Female Adolescents,Male Adolescent,Male Adolescents,Teen,Teenager,Youths
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults