title: Hereditary C2 deficiency: Genetic studies and association with the HL-A system.
abstract: Herediatary C2-deficiency has been shown to be transmitted asn an autosomal recessive characteristic. Recent evidence indicates that some genetic factors involved in the control of the complement (C) system in both man and mice are governed by genes localized within the major histocompatibility regionmthis study describes a large pedigree of the paternal family of a C2-deficient patient with systemic lupus erythematosusl It is shown that this condition is transmitted as an autosomal recessive trait, the heterozygous carriers having approximately half normal levels of C2. Furthermore, this trait was shown to be inherited in close linkage with an infrequent HL-A typw, 2,4A2. The maternal, C2-defective chromosome was shown to be transmitted by HL-AW10, W18 haplotypemthis same haplotype was described in a similar study by Fu et al. (6) to be associated with C2 deficiencymfinally, a third haplotype HL-A2,W18 carrying a defective C2 gene was demonstrated in a part of this pedigree.
mesh_terms: D003175:Complement C2 / Q000032:analysis / Q000172:deficiency*; D003165:Complement System Proteins / Q000172:deficiency*; D005260:Female; D006680:HLA Antigens; D006579:Heterozygote; D006649:Histocompatibility Antigens; D006650:Histocompatibility Testing; D006720:Homozygote; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000235:genetics; D008297:Male; D010375:Pedigree
chemical_list: D003175:Complement C2; D006680:HLA Antigens; D006649:Histocompatibility Antigens; D003165:Complement System Proteins