Genetic polymorphism of the sixth component of complement (C6) in the pig

Summary
Using agarose gel isoelectric focusing and immunoblotting with rabbit anti-rabbit C6, a genetic polymorphism has been found in the sixth component of complement (C6) in six breeds of pigs. The C6 locus was highly polymorphic. Family data indicated that pig C6 pheno-types were inherited by means of five codomonant alleles named C6 ^A, C6 ^B, C6 ^C, C6 ^D and C6 ^E at a single autosomal locus. C6 deficiency in two of 241 individuals tested was found, which suggested the presence of a null allele in pig populations. Marked breed differences among the gene frequencies and heterozygosities at C6 locus were observed.     

Genetic polymorphism of the sixth component (C6) of rat complement

The complement protein C6 has been shown to be genetically polymorphic in the rat. Isoelectric focusing of plasma samples from 19 inbred strains demonstrated two electrophoretically distinguishable migration patterns, each consisting of three bands. Breeding studies with the use of the BN and DA strains showed that the C6 patterns were inherited in a manner consistent with the co-dominant autosomal expression of two alleles (C6 A and C6 B). The distribution of the C6 alleles in a backcross mating was compared with eight independently segregating marker genes: RT1.A, RT2, Gdc -1, Igk-1, Hbb, Svp-1, Fh-1, and Es-6. There was no detectable linkage between C6 and any of these eight loci.     

Genetic polymorphism of the sixth component of complement (C6) in mice

Immunofixation after isoelectric focusing revealed two forms of mouse C6, C6A and C6M, both of which consist of two major protein bands and one or more acidic minor bands. They were distinguishable by their different isoelectric point (pI) ranges: C6M has more acidic pI ranges (pH < 6.2) than C6A (pH < 6.3). C6A was found in common inbred mice of Mus musculus domesticus, while C6M was found in inbred and wild mice of M. m. molossinus (Japanese wild mice, an Asian subspecies). Breeding experiments showed that these two forms of C6 were controlled by a single codominant autosomal locus. We propose the designation C-6 for this locus with two alleles, C-6 ^a and C-6 ^m , which encode for C6A and C6M, respectively. Linkage analysis indicated that the locus is not closely linked to the following loci: Idh-1, agouti, Amy-1, brown, Gpd-1, Mup-1, Pgm-2, Pgm-1, albino, Hbb, Es-1, Mod-1, Sep-1, Es-3, Igh-1, beige, Es-10, Sod-1, and C-3.     

Polymorphism of the sixth component of complement (C6) in the dog

Isoelectric focusing was used to identify five alleles at the locus determining the production of the sixth component of complement (C6) in the dog. Four of these alleles,C6 ¹, C6², C6⁴,andC6 ⁵,were studied in family pedigrees and shown to be inherited in a codominant autosomal fashion. All alleles except forC6 ⁴occurred commonly in the multiple breeds tested. This investigation was supported by Grant HL 17265 awarded by the National Institute of Heart, Lung, and Blood Diseases, DHEW, and by Grants CA 18105 and CA 31787 awarded by the National Cancer Institute.     

Genetic polymorphism of the sixth component of complement (C6) in the rhesus monkey.

With isoelectric focusing, the complement protein C6 has been shown to be genetically polymorphic in the rhesus monkey. Three codominant alleles of a single autosomal locus, Rh C6, have been recognized: C6A, C6B, and C6R, with gene frequencies of 0.592, 0.354, and 0.053 in a random rhesus monkey population. Hardy-Weinberg analysis of the phenotypic frequencies in this population yielded observed values very close to those expected. Both natural mating between individuals carrying the various alleles and artificial combinations of sera of the different C6 types demonstrate patterns consistent with this model. Analysis of several families of monkeys confirmed the Mendelian autosomal codominant inheritance with numbers of offspring very close to expected values and no offspring types inconsistent with the mating pair types.     

Genetic polymorphism and linkage of the sixth and seventh complement components (C6 and C7) in the common marmoset

Using polyacrylamide gel isoelectric focusing and standard specific hemolytic detection methods, genetic polymorphisms have been found in the sixth and seventh complement components (C6 and C7) in two laboratory groups of Common marmosets. The C6 locus is highly variable and the products of six alleles were observed; three C7 alleles were found. Comprehensive breeding data indicated that both sets of alleles are inherited in an autosomal codominant manner. Many of the C6 variants differed only by a minute charge interval. The C7 variant bands differed by large charge intervals and could only be clearly seen in plasmas that had been preincubated with neuraminidase. A linkage analysis of C6 and C7 phenotypes in three, two-generation families gives reasonable evidence that the two loci are linked in marmosets as they are in humans.This work was supported by a grant from the Advisory Board to the Research Councils.     

Genetic polymorphism and close linkage of two plasma protein loci in dogs

By using a simple method of two-dimensional horizontal electrophoresis, phenotypes of an unidentified plasma protein (PA4) were determined in 967 dogs belonging to 43 different breeds. Two codominant, autosomal alleles (F and S) of PA4 were reported. While many of the breeds of middle and north-eastern Asia (akita inu, Alaskan malamute, chow chow, samoyed, Siberian husky and Tibetan terrier) showed a substantial frequency (0.1 to 0.6) of the S allele, a majority of the European breeds had only the F allele. Evidence was provided that the PA4 locus is closely linked to the plasma pretransferrin 1 locus (PRT1). No recombinant was observed in 45 informative offspring studied. In nearly all breeds, the PA4 S allele was almost always in coupling phase with the PRT1 F allele.     

Genetic linkage relations of the sixth component of complement (C6)

Summary Linkage relations between the C6 and 33 other genetic marker loci have been analyzed in Norwegian pedigrees, including 114 matings with 388 informative children, by use of the MOSM computer program. No suggestion of linkage was found. Very close or close linkage (<0.06) has been ruled out for males between C6 and the following 19 marker loci: GPT, HLA+Bf, Rh, C3, Hp, PGM ₃, Km, Gm, Fy, Gc, AB0, Jk, GLO ₁, K, MNSs, PTC, ACP ₁, PGM ₁ and Pi. For several of the relations even loose linkage is unlikely.     

Genetic variation of the sixth component of complement (C6) in the Manx shearwater (Puffinus p. puffinus)

A polymorphism in the sixth complement component (C6) has been investigated by isoelectric focusing. The results indicate that C6 is coded by genes at a single autosomal locus. Six structural alleles have been identified, a null allele is also postulated. Five island colonies of Shearwater were investigated, two alleles C6 A and C6 B predominate in all sites.
The ability of rabbit C5 and C7 to combine successfully with avian C6 indicates the functional sites of these molecules are highly conserved.     

The genetics of the sixth and seventh components of complement in the dog: Polymorphism,linkage, locus duplication,and silent alleles

The complement components C6 and C7 exhibit genetic polymorphism in the domestic dog. In the case of C6, there is a single locus with a null allele and two structural alleles; in the case of C7, there are two linked loci, each with three structural alleles. There is a null allele or locus deletion at one of these loci. In all cases, inheritance is autosomal and codominant. The C7 loci are closely linked to each other and to C6. This complex is not close to the dog major histocompatibility complex (MHC) locus.     

Genetic polymorphism of horse serum protein 3 (SP3)

Summary. Two-dimensional agarose gel (pH 8.6)-horizontal polyacrylamide gel (pH 9.0) electrophoresis of horse serum samples, followed by general protein staining, revealed genetic polymorphism of an unidentified protein tentatively designated serum protein 3 (SP3). The SP3 fractions appeared distinctly when a 14% concentration of acrylamide was used in the separation gels. The 2-D mobilities of SP3 fractions were quite similar to that of albumin. Family data were consistent with the hypothesis that the observed SP3 phenotypes were controlled by four co-dominant, autosomal alleles ( D,F,I,S ). Evidence was provided that the F allele can be further divided into two alleles ( F ₁ and F ₂); the mobilities of F₁ and F₂ variants were very similar. Each of the SP3 alleles gave rise to one fraction and each of the heterozygous types showed two fractions. More than 600 horses representing five different breeds (Swedish Trotter, North-Swedish Trotter, Thoroughbred, Arab and Polish Tarpan) were typed for SP3, and allele frequency estimates were calculated. SP3 was highly polymorphic in all breeds studied.     

Genetic variation of the sixth component of complement (C6) in the Manx shearwater (Puffinus p. puffinus)

A polymorphism in the sixth complement component (C6) has been investigated by isoelectric focusing. The results indicate that C6 is coded by genes at a single autosomal locus. Six structural alleles have been identified, a null allele is also postulated. Five island colonies of Shearwater were investigated, two alleles C6 A and C6 B predominate in all sites. The ability of rabbit C5 and C7 to combine successfully with avian C6 indicates the functional sites of these molecules are highly conserved.     

Genetic polymorphism of complement component C8

Summary Extensive genetic polymorphism of complement component C8 was demonstrated by isoelectric focusing of serum or plasma samples followed by immunoblotting procedures. Using these methods, we could detect both - (C81) and (C82) chain polymorphisms in the same gel. Two-dimensional (2D) electrophoresis of C8 immunoprecipitates was used to obtain further information of the C8 patterns. Evidence was obtained that the C81 polymorphism resides in the structural gene of the C8 chain. Both C8 systems show autosomal, chiefly codominant inheritance, and the distribution of phenotypes agrees with the Hardy-Weinberg equilibrium. Our findings suggest at least five different alleles in the C81 system; the gene frequencies of the two most common ones, C81 ^*A and C81 ^*B being 0.59 and 0.39, respectively. In C82 we found evidence for at least three codominant alleles, the gene frequencies for the two most common ones, C82 ^*B and C82 ^*A being 0.94 and 0.05, respectively. In addition, family studies disclosed the existence of a null allele, C82 ^* Q0.     

Genetic polymorphism of the second component of human complement (C2)

Summary Proteins were separated by prolonged isoelectric focusing in polyacrylamide gels, whereupon C2 bands were detected by a specific hemolytic assay. This was performed by treating the gel with iodine to increase C2 activity, and then developing C2 bands with an agarose gel overlay containing sensitized sheep cells and diluted human serum as a complement source deficient in functional C2. The gene frequencies observed in a material of 122 unrelated adults were: C2¹:0.97 and C2²:0.03.C2 linkage relations and C2 haplotype associations have been examined a family material. It is concluded that C2 is very closely linked to HLA loci.     

补体第六成分（C6）在汉族5个群体中的多态分布

用聚丙烯酰胺等电聚焦技术和免疫酶标法,调查分析了汉族5个群体补体第六成分(C6)的遗传多态性,得出基因频率如下。郑州汉族:C6*A 0.4521、C6*B 0.5228、C6*B_2 0.0183、和C6*R 0.0068。兰州汉族:C6*A 0.4612、C6*B 0.5218和C6*B_2 0.0170。呼和浩特汉族:C6*A 0.4452、C6*B 0.5286、C6*B_2 0.0214和C6*R 0.0048。西安汉族:C6*A 0.4899、C6*B 0.4874、C6*B_2 0.0126和C6*R 0.0101。广东梅州客家人:C6*A 0.4569、C6*B 0.5152和C6*B_2 0.0279。C6*R为罕见等位基因之频率。     

Assignment of the gene locus for the sixth component (C6) of complement in mice to chromosome 15

A structural locus (C-6) for the sixth component of complement in mice is assigned to chromosome 15. Three-point linkage analysis indicated that the order of loci is C-6, Gpt-1, Gdc-1, and that the map distances are 25.9±4.9 between C-6 and Gpt-1, and 36.4±5.5 between C-6 and Gdc-1. Since Gdc-1 is more distal than Gpt-1, and C-6 is 26 cM away from Gpt-1, it is estimated that the C-6 is proximal to the centromere. In addition, a new C6 form found in AKR mice is described. We propose the designation C6B for it and C-6 ^b for the allele encoding C6B.Abbreviations used in this paper IEF isoelectric focusing - GPT glutamic-pyruvic transaminase - GDC L-glycerol 3-phosphate dehydrogenase - cM centimorgan     

Genetic polymorphism of human complement component C81 in the Japanese population

Summary Genetic polymorphism of human C81 has been investigated using polyacrylamide gel isoelectric focusing (PAGIEF) in the presence of 3.1 M urea followed by electroblotting with enzyme immunoassay. In 448 individuals phenotypes of C81 were classified into three common and four rare patterns, and these were considered to be controlled by two common alleles, C81^*A and C81^* B, and three rare alleles which were tentatively designated C81^*A1J and C81^*A2J for acidic variants and C81^*B1J for the basic variant. The alleles of C81^*A2J and C81^*B1J are new rare alleles, but C81^*A1J might correspond to C81^*A1 in the former studies. Family data were in accordance with the hereditary rules. The gene frequencies were estimated as C81^*A is 0.6228, C81^*B is 0.3672, C81^*A1J is 0.0078, C81^*A2J is 0.0011, and C81^*B1J is 0.0011, respectively. The gene frequencies of the two common alleles agreed approximately with other ethnic groups. PAGIEF of neuraminidase-treated plasma samples followed by electroblotting with enzyme immunoassay is applicable to the study of heterogeneity of C81.