A new hereditary single band variant of the Gc system

Summary A new single band variant (Gc Ar) or the Gc subtypes not identical with the known Gc variants has been detected in the plasma of a healthy blood donor by isoelectric focusing. Using this technique the variant is represented by a single band which has a similar isoelectric point to the Gc 1C2 anodal band. It is well known that the single band Gc phenotypes remain unaltered after neuraminidase treatment. Nevertheless, the new single band variant (Gc Ar) is altered after neuraminidase treatment as is Gc 2A3. After neuraminidase treatment, the Gc Ar band is affected and moved to the nearby position of the Gc 2 band. Investigation of the proband's family shows that the variant occurs combined with the common alleles Gc 1F, Gc 1S and that it has an autosomal dominant inheritance.     

A new hereditary variant of the PGM1 erythrocyte enzyme system determined by isoelectric focusing

Summary A new variant of the PGM _a ¹ erythrocyte enzyme system not identical with the known variants of the system has been detected in the hemolyzed red blood cells of a healthy blood donor by isoelectric focusing. Using this technique the variant is represented by two bands, a strong and slow one more cathodically located than the a3 band and a weak one in the position of the a2 band. Using agarose thinlayer or acetate foil electrophoresis the variant is represented only by a minimal cathodic broadening of the PGM₁ 1 band and therefore it is easily overlooked. Investigation of the propositus' family shows that the variant occurs combined with the common alleles PGM ₁ ^a1 , PGM ₁ ^a2 , and PGM ₁ ^a3 and that it has an autosomal dominant inheritance. Obviously the variant has a very low frequency.     

Gc subtypes identified by isoelectric focusing in Baboons (Papio hamadryas)

Summary Phenotyping for Gc variants by conventional electrophoresis in 835 Papio hamadryas baboons demonstrated a monomorphic population. Gc subtyping by polyacrylamide IEF gels, pH 4–6, on 394 of these baboons revealed the existence of two common alleles which we named Gc _Papio ¹ and Gc _Papio ² . Pedigree data confirmed the inheritance of a single locus, two allele system and the observed gene frequencies were 0.593 for Gc _Papio ¹ and 0.407 for Gc _Papio ² .     

A new BF F variant by polyacrylamide gel isoelectric focusing

Summary Polyacrylamide gel isoelectric focusing followed by electroblotting with enzyme immunoassay was done for the investigation of allotypes of properdin factor B (BF) in serum from 326 Japanese subjects. A new BF F variant tentatively designated BF*Fb1 (b=basic) was detected, the isoelectric point of each band of homozygous BF Fb1 being higher than of BF FF. Family data were in accordance with transmission by mendelian inheritance. The allele frequencies calculated from 326 Japanese subjects were 0.7945, 0.1825, 0.0215, and 0.0015 for BF*S, BF*F, BF*Fb1, and BF*F075, respectively, with that of variant BF*Fb1 being a polymorphic frequency. The distribution of phenotypes fitted the Hardy-Weinberg equilibrium.     

Five new Gc variants detected by isoelectric focusing in agarose gel

Summary Five new genetically determined Gc variants were observed by isoelectric focusing. Seven rare variants 1A4, 1C1, 1C3, 1C9, 1C11, 2A2, and 2A5 were also found in the material comprising Danish ans Swedish paternity cases. All the variants were further analysed by electrophoresis in agarose gel. Two of the new variants had double bands of which the anodal one was susceptible to neuraminidase treatment (Gc 1C13 and 1C14). The three other new variants appeared as a single band, which was unaffected by neuraminidase treatment (Gc 2A9, 2C5, and 2C6). The Gc Ar variant originally detected by electrophoresis was reexamined by isoelectric focusing and named 2C4.     

Population distribution in North and Central America of PGM1 and Gc subtypes as determined by isoelectric focusing (IEF)

Gc subtypes of 20 North and Central American populations and PCM₁ subtypes in 11 populations were analyzed to identify interpopulation variation of the respective gene frequencies for common alleles. A total of 23,304 phenotypings were done. Absolute heterozygosity levels (D) generally increased twofold when phenotyping by isoelectric focusing was compared with conventional electrophoresis. Graphic representation of the Gc subtypes and multivariate analysis to identify genetic affinities of the populations under study reveal genetic clusters consistent with major historical and geographical groupings of man.     

Group-specific component (Gc) and transferrin (Tf) subtypes ascertained by isoelectric focusing

Simultaneous subtyping of Gc and TfC by isoelectric focusing allows us to compute the following gene frequencies for the Belgian population: Gc1S = 0.543 Gc1F = 0.167 Gc2 = 0.290 TfC1 = 0.784 TfC2 = 0.206 TfB = 0.007 TfD = 0.003. The Gc bands were precipitated by sulfosalicylic acid instead of by immunofixation.     

Two new Bf S subtypes revealed by isoelectric focusing and immunofixation

Summary The genetic types of the properdin factor B were analyzed by isoelectric focusing on polyacrylamide gels and subsequent immunofixation. Sera from 516 unrelated, healthy individuals from Southern Germany were examined. Two new subtypes of the Bf*S allele were observed. They were provisionally named Bf*Sb1 and Bf*Sb2 (b = basic), since the position of their bands is located slightly towards the cathode. Whereas Bf Sb2 has, thus far, been found only in a single individual, Bf Sb1 was found in five unrelated persons and in a mother and her child indicating a simple codominant mode of inheritance. The combined frequency of the Bf*Sb alleles was calculated to be 0.0067.     

A new procedure for the determination of transferrinC (TfC) subtypes by isoelectric focusing

Summary The intensity of the silver staining of nucleolus organizing regions (NORs) and the frequency of chromosomal associations were studied before and after antithyroid treatment in seven and eight hyperthyroid patients, respectively.For one patient, the NOR staining was significantly more intense after treatment, while for another the opposite result was found. A higher stainability of chromosome 22 was observed after treatment in six of seven patients. The difference was significant for the group of patients considered as a whole but only for one patient considered separately. Chromosome 22 also showed an increased association frequency. For one patient, the number of large associations and the total number of associating chromosomes was also significantly increased after treatment.A decrease of associating chromosomes 14 and 21 such as was reported by Nilsson et al. (1975) after antithyroid treatment could not be found in our sample. The possible reason for this difference are discussed.Parts of this work are included in the doctoral (MD) thesis of CM     

Placental alkaline phosphatase types and subtypes determined by agarose gel electrophoresis and separator isoelectric focusing

Summary Two techniques for phenotyping the human placental alkaline phosphatase system were developed: high-voltage agarose-gel electrophoresis and thin-layer separator isoelectric focusing on agarose. These methods enabled a more rapid and sensitive phenotyping of all common phenotypes than the traditionally employed starch-gel electrophoresis. An extended polymorphism of placental alkaline phosphatase was revealed by isoelectric focusing. The existence of two suballeles of Pl¹ allele and two suballeles of Pl² allele was postulated.     

Linkages among zein genes determined by isoelectric focusing

Summary Genetic control of the major zein polypeptides in maize (Zea mays L.) was studied by isoelectric focusing (IEF) in agarose. Linkage relationships were determined by making a number of crosses, then determining the expression of zein polypeptides in backcross seeds. Chromosome linkages were determined by using the markers sugary-1 (for chromosome 4), yellow-8, and a waxy 7–9 translocation (for chromosome 7). Nine zeins were in one linkage group on chromosome 4, six in another linkage group on chromosome 4, and four zeins were in one linkage group on chromosome 7. Some IEF single bands consisted of at least two polypeptides, which were detected by subsequent sodium dodecyl sulfate polyacrylamide gel electrophoresis, by aberrant ratios in backcrosses, or by differing recombination percentages. One zein occurred only in homozygous sugary-1 seeds. Three sets of closely-linked zeins were noted that occurred together almost exclusively in certain inbreds.Cooperative investigations of the U.S. Department of Agriculture, Agricultural Research Service, and the Illinois Agricultural Experiment Station, Department of Agronomy, University of Illinois, Urbana, USAMention of firm names or trade products does not imply that they are endorsed or recommended by the U.S. Department of Agriculture over other firms or similar products not mentioned     

Albumin Paris 2: a new genetic variant distinguished by isoelectric focusing.

Until recently, the characterization of genetic variants of human serum albumin was performed by electrophoretic typing prior to the determination of their amino acid substitutions. We describe a procedure using isoelectric focusing in the presence of urea for the analysis of the genetic variation of albumin. This procedure allowed a clear distinction of a new variant, previously found to be identical with albumin Sondrio according to its relative electrophoretic mobilities at 3 pHs. This new variant, the third rare albumin allotype identified in the Ile-de-France region, was called albumin Paris 2.     

Phosphoglucomutase (PGM1) subtypes in a Finnish population determined by isoelectric focusing in agarose gel

The red cell enzyme phosphoglucomutase first locus (PGM1) phenotypes of 639 adult Finns were determined by isoelectric focusing in agarose gel. All the ten commonly occurring phenotypes were detected and the frequencies of the four alleles at the PGM1 locus were as follows: PGMa11 = 0.5313, PGMa21 = 0.1800, PGMa31 = 0.2199 and PGMa41 = 0.0689. The PGM1 phenotypes of 221 mothers with 228 offspring were in accordance with autosomal codominant inheritance.     

Group-specific component (Gc) 'subtypes' of Gc1 by isoelectric focusing in US blacks and whites.

Isoelectric focusing was applied to the Gc polymorphism. In agreement with Constans et al., we found two common 'subtypes' of Gc1 that could not be identified by conventional electrophoretic procedures. They are labeled Gc1F and Gc1S. Gc1F has a slightly lower isoelectric point than Gc1S. In groups of US blacks the allele frequencies were for Gc1F; 0.732 and for Gc1S; 0.147. In whites these figures were 0.149 and 0.572. We also found GcAb in blacks with a frequency of 0.015. The concentrations in serum of Gc protein as measured by radial immunodiffusion did not differ according to phenotype.     

Gc revisited: Six further Gc-phenotypes delineated by isoelectric focusing and by polyacrylamide gel electrophoresis

Summary Six newly observed Gc variants are described. The variants Gc 1A10, 1A11, 1A12, 1A13, and 1C11 have double band patterns. The anodal bands of these variants are susceptible to neuraminidase treatment. Gc 2A7 is a single band variant which is not altered by neuraminidase incubation. Polyacrylamide gel isoelectrofocusing with immunofixation and polyarcylamide gel electrophoresis appear to be efficient methods for the analysis of the Gc system.     

Heterogeneity and specificity of human anti-insulin antibodies determined by isoelectric focusing

Anti-insulin antibodies are present in the majority of insulin treated diabetics, and in some cases these antibodies have been found to be highly specific for limited epitopes on the molecule. To determine how the human response differs from that seen in inbred animals, we have examined the heterogeneity and specificity of human anti-insulin antibodies by isoelectric focusing (IEF). In addition, we have used human insulin to examine the extent of autoreactivity in the serum of subjects treated with animal insulins. The majority of diabetic sera exhibited complex IEF spectra that were composed of discrete bands and unresolved smears. Autoradiography using 125I-beef, pork, and human insulin revealed some affinity differences; however, the predominant antibodies were capable of binding all insulins, including human. These specificity studies were extended by comparing competitive inhibition with excess cold insulins, and sera with highly specific binding of the A chain loop of beef insulin were identified. The spectra by IEF of these highly specific sera were found to be variable. Our results indicate that the majority of insulin-treated diabetics develop a heterogeneous antibody response that is more complex than the response of inbred animals and includes reactivity with autologous insulin. Although infrequent, individuals having antibodies directed at limited regions of the molecule can be identified and will provide valuable tools for dissecting this complex response.     

Reliable classification of six Pi M subtypes by separator isoelectric focusing.

For the first time, segregation of three common PiM alleles in family material is verified by application of separator isoelectric focusing. A new nomenclature system for the Pi M subtypes is used, whereby the common subtypes are designated according to their physicochemical properties; the most anodal type is called Pi M1, the intermediary one Pi M2, and the most cathodal variant Pi M3 (previously called Pi M2). Pi gene frequencies from Finnish, Dutch and Black populations are presented. The PiM2 allele was rather high in Finns (0.12) but low (0.04) in the West African Bozo. The PiM3 was found with a frequency of 0.13 in Dutch, 0.08 in Finns and 0.02 in Bozo. A previous Finnish sample was retested with the new subtyping method and the six-subtype distribution was found to be in good Hardy-Weinberg equilibrium. The validity of the Pi polymorphism for population genetics, linkage analysis and parentage testing is discussed.