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C Rittner

Publications and source records attributed to C Rittner.

At least 91 records · Page 5Linked to original sources
PubMed1989

Possible association of sudden infant death with partial complement C4 deficiency revealed by post-mortem DNA typing of HLA class II and III genes.

Based on evidence of an increased rate of respiratory infections in sudden infant death (SID) infants as well as the observation of familial occurrence, we analysed in a retrospective study class II and class II genes of the major histocompatibility complex in 40 cases of SID by Southern blot analysis of DNA obtained post mortem from tissue samples. In 24 cases, the parents were interviewed and confirmatory human lymphocyte antigen (HLA) and DNA typing was carried out. Using HLA-DR beta and -DQ beta probes, no evidence of an abnormal HLA-DR frequency distribution in SID infants was detected (P = 0.97). Using DNA probes for the tandemly arranged complement C4 and steroid 21-hydroxylase genes, an increased number of C4B gene deletions in SID cases was found. The increase in C4 gene deletions was significant (P = 0.0125) in infants with recurrent infections. These data indicate a possible role of partial C4 deficiency as a genetically predisposing risk factor in SID.

Complement C4↗
PubMed1989

DNA polymorphism of the human complement C8 beta gene: formal genetics and intragenic localization.

The eighth component of human complement consists of three subunits of different molecular mass, which are coded for by three separate genetic loci. Polymorphisms have been described at the protein level for the alpha and beta subunits by means of sodium dodecyl sulfate gel electrophoresis and isoelectric focusing. Using a full-length human C8 beta cDNA probe, we have studied more than 100 individuals by Southern blot analysis to detect DNA polymorphisms. We have found two restriction fragment length polymorphisms (RFLPs) with the enzymes Taq I and Bam HI. The Taq I polymorphism is defined by two alleles, i.e., a single 4.9 kb fragment or two 2.8/2.1 kb fragments. The allele frequencies are 0.68 and 0.32, respectively. The second RFLP with Bam HI is correlated with the Taq I variants: 3 kb Bam HI; 4.9 kb Taq I and 3.3 kb Bam HI; 2.8/2.1 kb Taq I. Both RFLPs could be mapped to the 3' portion of the C8 beta gene. Based on the size of genomic restriction fragments, the C8 beta gene can be estimated to have a size of 32-36 kb. Because of the even frequency distribution, the C8 beta DNA polymorphisms may be useful in gene mapping and disease association studies.

Alleles↗
PubMed1989

[Roentgen identification of unknown cadavers and living persons].

Four cases of successful x-ray identification of unknown dead with progressed postmortem changes are reported. Some of the x-ray plates are 25 years old and have been taken during growth process. Skull and spine are especially qualified for identification because the skeleton shows individual, highly specific markers in these regions which do not change during live and after death. The exclusion of identity was possible with regard to a 50 years old patient. She presented a 19 years old urogram as her own to receive a pension after an occupational accident in 1970. Two other cases of x-ray identification (tibia operation and skull) have been already described by us (1988).

Adult↗
PubMed1988

Family studies in scleroderma (systemic sclerosis) demonstrating an HLA-linked increased chromosomal breakage rate in cultured lymphocytes.

An increased chromosomal breakage rate (ICBR) was found in 27 of 28 patients with scleroderma (systemic sclerosis, SS) - 5 with the syndrome including calcinosis cutis, Raynaud phenomenon, esophagus hypomotility, sclerodactyly and telangiectasia (CREST), 4 incomplete CREST, 1 overlapping syndrome, 18 progressive systemic sclerosis (PSS). Not only the patients, but also about half of their first-degree relatives showed an increased chromosomal breakage rate (more than 5 breaks per 100 metaphases). This character segregated as a dominant marker in nine families of scleroderma patients. In the six informative of the nine families, the ICBR trait showed close linkage with the HLA region on chromosome 6 (total lod score 5.5 at theta = 0). In these families, ICBR was predominantly observed in linkage with HLA haplotype A1, Cw7, B8, C4AQ0B1, DR3 which is frequently observed in autoimmune diseases. The nature of the agent inducing chromosomal breakage in cultured lymphocytes of some, but not all family members of scleroderma patients remains to be clarified.

Cells, Cultured↗
PubMed1988

Antigenic determinants expressed by human C4 allotypes; a study of 325 families provides evidence for the structural antigenic model.

The antigenic determinants of human C4 have been defined by human IgG antisera, Rodgers (Rg) and Chido (Ch), in hemagglutination-inhibition assays (HAI). Eight (2 Rg and 6 Ch) are of high frequency, greater than 90%, and 1, WH, is of low frequency, 15%. The phenotypic combinations are complex; generally, C4A expresses Rg, and C4B has Ch, but reverse antigenicities have been established both by HAI and by sequence data of selected C4 allotypes. A study of 325 families provides data on the antigenic expression of each C4 allotype and demonstrates strong associations. A structural model for the antigenic determinants of C4 proteins has been proposed and is completely supported by the family material. Of the 16 possible antigenic combinations for C4 proteins, only 3 are undetected. A new Ch combination has been recorded in two French families. The reported sequence variation within the C4d region can account for the antigenic determinants but leaves the location of electrophoretic variation in C4 still unclear.

Blood Group Antigens↗
PubMed1987

Chromosomal assignment of human cytochrome P-450 (debrisoquine/sparteine type) to chromosome 22.

In order to determine on which chromosome the gene controlling human cytochrome P-450 (debrisoquine/sparteine type) is located a linkage study of polymorphic sparteine oxidation (PSO) to various polymorphic markers was carried out. Positive information for linkage between PSO and the P1 blood group was obtained with a maximal LOD-score of LOD = 3.35 for both male and female recombination fraction estimates of theta m = theta f = 0.0. The P1 blood group has been recently mapped to the long arm of chromosome 22. Thus it can be concluded that the gene controlling human cytochrome P-450 (debrisoquine/sparteine) is situated on the long arm of chromosome 22 in close vicinity to P1.

Alleles↗
PubMed1986

Polymorphism of the human complement C4 and steroid 21-hydroxylase genes. Restriction fragment length polymorphisms revealing structural deletions, homoduplications, and size variants.

Several autoimmune disorders as well as congenital adrenal hyperplasia (CAH) are either associated or closely linked with genetic variants of the fourth component of complement (C4A and C4B) and the enzyme steroid 21-hydroxylase (21-OH). These proteins are encoded by genes that are located downstream from the genes for complement proteins, C2 and factor B (BF) between HLA-B and -DR in the major histocompatibility complex (MHC). Previous studies of variants and null alleles were based on electrophoretic mobility of C4 protein and linkage with disease phenotypes. These data did not permit analysis of the basis for the observed null alleles and duplicated variants. We studied this region of the MHC in 126 haplotypes for a structural analysis of the four adjacent loci, C4A, 21-OHA, C4B, and 21-OHB. About half of the C4 genes typed as C4 null are deleted and several unrecognized homoduplicated C4 alleles were detected. Hence the frequencies of different C4 structural variants must be recalculated based on a direct analysis of the genes. Analysis of the C4/21-OH genes of patients with the classical (salt-wasting) form of CAH showed that some involve a deletion of the C4B and 21-OHB genes; whereas for two only the 21-OHB gene is deleted, i.e., the C4B gene is present. Together, these data provide a better understanding of the mechanisms generating and importance of deleted C4 and 21-OH null alleles in human disease.

Adrenal Hyperplasia, Congenital↗
PubMed1986

Human C81 (alpha-gamma) polymorphism: detection in the alpha-gamma subunit on SDS-PAGE, formal genetics and linkage relationship.

The molecular basis of human C81 (alpha-gamma) polymorphism could be elucidated by immunoprecipitation of human C81 allotypes and separation of the alpha-gamma and beta subunits on sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE) under nonreducing conditions. If the C8 molecules were completely reduced, C81 polymorphism was no longer detectable on SDS-PAGE. It is concluded that C81 variation depends on charge rather than molecular weight differences. Four C81 allotypes, the common A and B and two rare allotypes provisionally named A2 and B1, could be distinguished. The rare allotype A1 as detected by isoelectric focusing with subsequent C8 (alpha-gamma)-dependent functional overlay could no longer be visualized on SDS-PAGE. This allotype may therefore be elicited only in the intact C8 molecule. The beta-chain polymorphism named C82, probably also reflecting charge variation of the C8 molecule, could not be detected yet on SDS-PAGE. The distributions of C81 phenotypes and their respective allele frequencies were in good agreement with previously reported data. In the study of 30 families with 100 offspring, no deviation from the rule of at least four codominant alleles at one genetic locus was found. Linkage between C81 gene(s) and PGM1a encoded on chromosome 1 could be confirmed. The following estimates were obtained: (formula; see text) with S theta being the standard error of the maximum likelihood estimate theta. The new technique for allotyping human C81 at the subunit may provide a new tool for the differentiation of qualitative and quantitative variation of the eighth component of human complement.

Alleles↗
PubMed1984

Population and formal genetics of the human C81(alpha-gamma) polymorphism.

One hundred and ninety-six unrelated healthy individuals and 30 families with 75 offspring have been studied for the C81(alpha-gamma) polymorphism. The following allele frequencies were calculated: C81*A = 0.5536; C81*B = 0.4286; C81*A1 = 0.0178. Observed and expected phenotype frequencies were in a good agreement according to the Hardy Weinberg law. No exceptions from the mode of inheritance were found. In family W the segregation of the rare allele C81*A1 could be followed. Comparing the results of this study with previous data from Boston and Oslo, a combined technology including C8-dependent lysis and C8 structural variation is suggested for future investigations.

Alleles↗
PubMed1984

Reactivity pattern of 15 HLA-Dw1 homozygous typing cells in primary mixed lymphocyte culture.

The Dw1 specificity was highly correlated with the serologically determined HLA-DR1 antigen in the Eighth International Histocompatibility Workshop 1980. By testing a large number of HLA-Dw1, DR1 defined homozygous typing cells (HTC) in a checkerboard primary mixed lymphocyte reaction, on a panel of about 30 HLA-DR1 heterozygous individuals, and in family segregation, three Dw1 "subtypes" could be defined in association with certain HLA-A, -B, and -C-antigens. HTC TA, FRI, and FRA carrying the HLA haplotypes A11, B35, Cw4 or A3, B35, Cw4 in the homozygous state gave positive typing results with most HLA-DR1 positive panel members and stimulated only four other Dw1 HTCs (SRR less than or equal to 35%). In contrast to this operationally "broad" specificity, Dw1-HTC-HEN (HLA-A2, B44, C-, homozygous) was non-stimulatory to all HTCs except one, but gave high responses against these, leading to the definition of a "narrow" specificity included in the "broad" one. Another such "narrow" specificity was represented by HTC FEE (HLA-A2, B27, Cw2 homozygous). Typing patterns with FEE were mostly different from those defined with other HTC. In family studies a specific typing pattern for this HTC could be shown to segregate with HLA. However, within some of these responses a contribution of the HLA haplotype in the trans position must be assumed.

Alleles↗
PubMed1984

Genetics of human C4 polymorphism: detection and segregation of rare and duplicated haplotypes.

Applying a combined technology for the detection of allotypic variation of the fourth component of human complement (C4), including immunofixation with anti-C4 and C4-dependent lysis after agarose electrophoresis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis of C4 to separate the C4A and B alpha-chains, and the determination of Rodgers (Rg) and Chido (Ch) determinants of C4 in serum and at the blotted C4 alpha-chains, we detected rare human C4 allotypes and studied the genetic linkage. Partial inhibitors (p.i.) of anti-Rg and anti-Ch sera were found; the C4A51 allotype characterized as Rg p.i. and the C4A1 and C4B51 allotypes as Ch p.i. were genetically inherited. The C4A1 allotype has a unique Rg- Ch+ C4A alpha-chain. Duplicated C4A loci, A*3, A*2, and A*5, A*2 were both associated with a C4BQO and the HLA haplotype A3-Cw4-Bw35-DR1. These additions to the already known extensive C4 polymorphism may help to sort out their significance for the biological functions of human C4.

Complement C4↗
PubMed1984

Partial C4 deficiency in subacute sclerosing panencephalitis.

In an immunogenetic study, 23 subacute sclerosing panencephalitis (SSPE) patients and their families were studied for the HLA region markers HLA-A, B, C, DR, BF, C2, C4A, C4B, GLO I, and PGM3. In addition, C3, C4, and factor B serum levels were determined. A highly significant association of C4A QO with SSPE was found. Furthermore, two rare haplotypes, C4A QOB QO, two C4ACh+ allotypes, and four Ch partial inhibitors were detected, which possibly impair the function of the C4 molecules. HLA-DR5 was increased. In addition, a number of rare HLA-A, C, B, DR haplotypes were observed. It is postulated that rare C4 molecular deficiency might be a predisposing factor in the pathogenesis of SSPE.

Complement C4↗
PubMed1984

[Population genetics and the coagulation factor XIII A polymorphism].

Platelets of 235 blood donors were typed for FXIII A polymorphism using agarose gel electrophoresis with subsequent immunofixation with anti-FXIIIA serum. The allele frequencies obtained (FXIIIA 1 = 0.7787, FXIIIA 2 = 0.2212) are in agreement with previously published data for Caucasoid populations. FXIIIA may be an additional valuable marker for paternity and linkage studies.

Alleles↗