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S T Reeders

Publications and source records attributed to S T Reeders.

At least 37 records · Page 2Linked to original sources
PubMed1994

Mutations in the type IV collagen alpha 3 (COL4A3) gene in autosomal recessive Alport syndrome.

A group of 22 unrelated patients with sporadic or non-X-linked Alport syndrome were screened for mutations in the non-collagenous domain of the type IV collagen alpha 3 (COL4A3) chain gene. The five 3'-exons of this gene, located on chromosome 2qter, were tested by single strand conformation polymorphism analysis and direct sequencing. One patient was heterozygous and another homozygous (Mochizuki et al., Nature Genetics, in press) for a deletion of five nucleotides. A third patient appeared to be a compound heterozygote for two different nonsense mutations. In two patients and the father of a deceased patient we found a heterozygous substitution of an evolutionary conserved leucine by proline. However, segregation data of the mutation and a COL4A3/COL4A4 CA-repeat marker in their families argued against a causative role of the missense mutation. Even drastic changes of strongly conserved amino acids, as in the Leu36Pro case, may not be significant. Autosomal recessive inheritance due to pathogenic COL4A3 mutations accounts for at least 13% of Alport syndrome cases in this sample. It is concluded that COL4A3 is a major gene in the genetically and clinically heterogeneous Alport syndrome.

Base Sequence↗
PubMed1994

Linkage disequilibrium in the region of the autosomal dominant polycystic kidney disease gene (PKD1).

The gene for autosomal dominant polycystic kidney disease (PKD1) is located on chromosome 16p, between the flanking markers D16S84 and D16S125 (26.6prox). This region is 750 kb long and has been cloned. We have looked at the association of 10 polymorphic markers from the region, with the disease and with each other. This was done in a set of Scottish families that had previously shown association with D16S94, a marker proximal to the PKD1 region. We report significant association between two CA repeat markers and the disease but have not found evidence for a single founder haplotype in these families, indicating the presence of several mutations in this population. Our results favor a location of the PKD1 gene in the proximal part of the candidate region.

Alleles↗
PubMed1993

Deletion of the paired alpha 5(IV) and alpha 6(IV) collagen genes in inherited smooth muscle tumors.

The gene encoding alpha 6(IV) collagen, COL4A6, was identified on the human X chromosome in a head-to-head arrangement and within 452 base pairs of the alpha 5(IV) collagen gene, COL4A5. In earlier studies, intragenic deletions of COL4A5 were detected in a subset of patients with Alport syndrome (AS), a hereditary defect of basement membranes. In some families, AS cosegregates with diffuse leiomyomatosis (DL), a benign smooth muscle tumor diathesis. Here it is shown that patients with AS-DL harbor deletions that disrupt both COL4A5 and COL4A6. Thus, type IV collagen may regulate smooth muscle differentiation and morphogenesis.

Amino Acid Sequence↗
PubMed1993

Specificity of Goodpasture autoantibodies for the recombinant noncollagenous domains of human type IV collagen.

Type IV collagen has recently emerged as a family composed of five known chains (alpha 1-alpha 5), each of which contains a carboxyl-terminal noncollagenous domain (NC1) of approximately 230 amino acids. The NC1 domain of the alpha 3(IV) chain is the probable target for autoantibodies in patients with Goodpasture syndrome (GP), as evidenced from studies employing bovine type IV collagen. In the present experiments, the specificity of GP antibodies for the five NC1 domains of human type IV collagen was determined by using recombinant NC1 domains as the antigen. cDNAs encoding each NC1 domain were expressed in E. coli as fusion proteins with a 6-histidine amino-terminal leader. The recombinant NC1 monomers r alpha 1(IV), r alpha 2(IV), r alpha 3(IV), r alpha 4(IV), and r alpha 5(IV) were purified by affinity chromatography to the fusion protein using a nickel resin column, and then characterized by electrophoresis and immunoblot analysis using chain-specific peptide antibodies. The specificity of GP antibodies from four patients to these recombinant proteins was then further evaluated by immunoblot analysis and enzyme-linked immunosorbent assay measurements. The GP antibodies reacted strongly with the r alpha 3(IV) NC1 domain but were not reactive when tested against the other four recombinant monomers. In contrast, neither antisera from patients with two other forms of autoimmune disease (anti-tubular basement membrane disease and Wegener's syndrome) nor normal control sera bound to any of the recombinant NC1 moieties. These results unambiguously establish that GP antibodies are specifically targeted to the NC1 domain of the alpha 3(IV) chain of human type IV collagen. The findings also establish a methodology for large scale preparation of r alpha 3(IV) NC1 domain for use in diagnostic tests and development of therapeutic procedures and offer a strategy for the elucidation of a more complete GP epitope by site-directed mutagenesis.

Amino Acid Sequence↗
PubMed1993

A transducin-like gene maps to the autosomal dominant polycystic kidney disease gene region.

A novel human gene (sazD) that maps to the autosomal dominant polycystic kidney disease region shares sequence similarity with members of the beta-transducin superfamily. The cDNA sazD-c predicts an approximately 58-kDa protein (sazD) with seven internal repeats, similar to the WD-40 motif of the transducin family. The size of this protein family has been expanding rapidly; however, neither the structure nor the function of this repeated motif is known. Preliminary data do not suggest that sazD is mutated in patients with polycystic kidney disease.

Adult↗
PubMed1993

Molecular characteristics of the Goodpasture autoantigen.

Goodpasture syndrome is an autoimmune disease causing rapidly progressive glomerulonephritis and pulmonary hemorrhage. The clinical manifestations are caused by autoantibodies that bind to a constituent, termed the Goodpasture autoantigen, of alveolar and glomerular basement membranes. Searches for the identity of this constituent have recently culminated in the discovery of two new chains (alpha 3 and alpha 4) of type IV collagen and the identification of the alpha 3 chain as the Goodpasture autoantigen. The gene, COL4A3, encoding this autoantigen was recently cloned and localized to the q35-37 region of chromosome 2. The major protomeric form of the alpha 3 chain is a homotrimer. The alpha 3-protomers associate through NC1-to-NC1 interactions mainly with each other to form a suprastructure, although some associate with protomers containing the alpha 1(IV) and alpha 2(IV) chains. The alpha 3-protomers also form suprastructures involving triple helical interactions of three or more protomers. The Goodpasture epitope is localized to the carboxylterminal region of the alpha 3(IV) chain, encompassing the last 36 residues of the chain, as the primary interaction site, and its structure is discontinuous.

Amino Acid Sequence↗
PubMed1993

A kindred exhibiting cosegregation of an overlap connective tissue disorder and the chromosome 16 linked form of autosomal dominant polycystic kidney disease.

Autosomal dominant polycystic kidney disease (ADPKD) is a disorder of adult onset manifested by bilaterally enlarged cystic kidneys frequently associated with progressive renal failure. The mutated gene (PKD1) responsible for 85 to 95% of cases has been localized to a small segment on the distal tip of the short arm of chromosome 16. A clinical spectrum of heritable connective tissue disorders that remain unclassifiable under the present nosology but that contain elements of the Marfan's syndrome have previously been described. The genetic localization and molecular basis of such overlap connective tissue disorders (OCTD) have not been elucidated. In this report, a kindred in which ADPKD and OCTD appear to cosegregate is described. The connective tissue phenotype in this family includes aortic root dilation, aortic and vertebral artery aneurysms with dissection, and aortic valve incompetence, as well as pectus abnormalities, pes planus, joint laxity, arachnodactyly, scoliosis, dolichostenomelia, and high arched palate. ADPKD was manifest primarily as bilateral renal cysts with or without renal failure. The DNA of all living family members was studied with markers recognizing polymorphic loci flanking the PKD1 region (3'HVR and O90a), as well as markers from the loci of chromosomes 15 and 5, associated with fibrillin genes FBN1 and FBN2, respectively. In this kindred of 20 family members traced through five generations, cosegregation of ADPKD and the OCTD phenotype was observed in 12 of 12 meioses and 3 of 3 phase known. Both markers for PKD1 were tightly linked to both ADPKD and OCTD, whereas there was no evidence for linkage with either fibrillin locus. In this family, the ADPKD and OCTD mutations are genetically linked. The presence of OCTD with ADPKD identifies a group of patients at significantly greater risk for sudden death from aortic root and other vascular aneurysmal dissection and rupture.

Adolescent↗
PubMed1993

CECIL: a database for storing and retrieving clinical and molecular information on patients with Alport syndrome.

CECIL is a database that stores clinical and molecular information on patients with Alport syndrome. The clinical component of CECIL is specific to Alport syndrome; the component that stores and manipulates molecular data can be used for any disease caused by a gene mutation, such as cystic fibrosis. While offering the ability to retrieve patient data through compound Boolean queries, CECIL also offers the ability to manipulate sequence information in various ways. In particular, CECIL can perform an augmented sequence alignment of an abnormal (patient) DNA sequence with a reference sequence. CECIL is currently being used by members of the International Alport Syndrome consortium. We describe CECIL's features and discuss the design decisions made in generalizing CECIL's architecture.

Base Sequence↗
PubMed1993

Positional cloning approach to the dominant polycystic kidney disease gene, PKD1.

Positional cloning is a powerful strategy for identifying the site of disease-producing mutations when the underlying biochemical defect is unknown. The approach also offers new methods for the presymptomatic diagnosis of genetic disease. Using these methods we have localized the PKD1 gene, mutated in the majority of PKD1 families, to a small (500 kb) segment of chromosome 16, band p13.3. Virtually all of this interval has been cloned in cosmids and lambda bacteriophage. Over 20 sets of non-overlapping cDNA clones have been isolated from the region. Sequence and mutational analyses are currently underway. In addition, a set of polymorphic clones has been identified for presymptomatic diagnosis. Included in this set are several highly variable [CA]n microsatellite repeats. These highly informative markers can be rapidly assayed from a small amount of genomic DNA using the polymerase chain reaction. Despite these advances, presymptomatic diagnosis cannot be established with certainty in many families. However, identification of the PKD1 gene itself will eventually allow diagnosis by direct detection of mutations.

Base Sequence↗
PubMed1992

The alpha 4(IV) chain of basement membrane collagen. Isolation of cDNAs encoding bovine alpha 4(IV) and comparison with other type IV collagens.

Renal basement membranes are believed to contain five distinct type IV collagens. An understanding of the specific roles of these collagens and the specificities of their interactions will be aided by knowledge of their comparative structures. Genes for alpha 1(IV), alpha 2(IV), alpha 3(IV), and alpha 5(IV) have been cloned and the deduced peptide sequences compared. A fifth chain, alpha 4(IV), has been identified in glomerular and other basement membranes. Using a polymerase chain reaction-based strategy and short known peptide sequences from the noncollagenous domain (NC1), we have cloned and characterized partial bovine cDNAs of alpha 4(IV). Sequence analysis shows that this molecule has characteristic features of type IV collagens including an NH2-terminal Gly-X-Y domain which is interrupted at several points and a COOH-terminal NC1 domain with 12 cysteine residues in positions identical to those of other type IV collagens. Within the NC1 domain bovine alpha 4(IV) has 70, 59, 58, and 53% amino acid identity with human alpha 2(IV), alpha 1(IV), alpha 5(IV), and alpha 3(IV), respectively. Alignment of the peptides also shows that alpha 4(IV) is most closely related to alpha 2(IV). Nevertheless, in the extreme COOH-terminal region of the NC1 domain there are structural features that are unique to alpha 4(IV). Cloning of the region of alpha 4(IV) that encodes the NC1 domain allows comparison of all five type IV collagens and highlights certain regions that are likely to be important in the specificities of NC1-NC1 interactions and in other discriminant functions of these molecules.

Amino Acid Sequence↗
PubMed1992

Construction of a map of chromosome 16 by using radiation hybrids.

A human-hamster cell hybrid carrying a single copy of chromosome 16 as the only human genetic material was irradiated with a single dose of gamma-rays (7000 rads; 1 rad = 0.01 Gy) and then fused with a thymidine kinase-deficient hamster cell line (RJKM) to generate radiation hybrids retaining unselected fragments of this human chromosome. In two experiments, 223 hybrids were isolated in hypoxanthine/aminopterine/thymidine (HAT) medium and screened with 38 DNA probes, corresponding to anonymous DNA or gene sequences localized on chromosome 16. The most likely order and location of the 38 DNA sequences were established by multiple pairwise analysis and scaled to estimate physical distance in megabases. The order and the distances thus obtained are mostly consistent with available data on genetic and physical mapping of these markers, illustrating the usefulness of radiation hybrids for mapping.

Chromosome Mapping↗
PubMed1992

Colocalization of the genes for the alpha 3(IV) and alpha 4(IV) chains of type IV collagen to chromosome 2 bands q35-q37.

Each type of basement membrane in man contains between two and five genetically distinct type IV collagens: alpha 1(IV)-alpha 5(IV). Genes for alpha 1(IV), alpha 2(IV), alpha 3(IV), and alpha 5(IV) have been isolated. We have recently isolated partial cDNAs for the fifth member of the family, designated alpha 4(IV). On the basis of comparison of the deduced peptide sequences of all five chains, the type IV collagens can be divided into two families: alpha 1-like, comprising alpha 1(IV), alpha 3(IV), and alpha 5(IV); and alpha 2-like, comprising alpha 2(IV) and alpha 4(IV). Genes encoding the alpha 1(IV) and alpha 2(IV) chains (COL4A1 and COL4A2) both map to human chromosome 13q34 and have been shown to be transcribed from opposite DNA strands using a common bidirectional promoter that allows coordinate regulation of the two chains. Indeed, these two chains are commonly found together in basement membrane and form [alpha 1]2.[alpha 2] heterotrimers. Whereas alpha 1(IV) and alpha 2(IV) have been found in all basement membranes studied hitherto, it has been shown that alpha 3(IV) and alpha 4(IV) are found in only a subset of basement membranes. In basement membranes where either of these molecules is present, however, they are found together. In view of this relationship and the structural similarities between alpha 1(IV) and alpha 3(IV) and between alpha 2(IV) and alpha 4(IV), we hypothesized that COL4A3 and COL4A4, the genes encoding alpha 3(IV) and alpha 4(IV), respectively, have a genomic organization similar to that of COL4A1 and COL4A2.(ABSTRACT TRUNCATED AT 250 WORDS)

Basement Membrane↗
PubMed1992

Human-mouse homologies in the region of the polycystic kidney disease gene (PKD1).

Autosomal dominant polycystic kidney disease (PKD1) is linked to the alpha-globin locus near the telomere of chromosome 16p. We established the existence of a conserved linkage group in mouse by mapping conserved sequences and cDNAs from the region surrounding the PKD1 gene in the mouse genome. Results obtained with the BXD recombinant strain system and somatic cell hybrids show the homologous region to be located on mouse chromosome 17 near the globin pseudogene Hba-ps4, an unprocessed alpha-like globin gene. The markers we mapped are widely distributed over the region known to contain the PKD1 gene, and it is therefore likely that the mouse homologue of PKD1 is also located on mouse chromosome 17.

Animals↗
PubMed1992

The gene for autosomal dominant polycystic kidney disease lies in a 750-kb CpG-rich region.

PKD1, the locus most commonly affected by mutations that produce autosomal dominant polycystic kidney disease (ADPKD), has previously been localized to chromosome 16p13.3. Since no cytogenetic abnormalities have been found in association with ADPKD, flanking genetic markers have been required to define an interval--the PKD1 region--that contains the PKD1 gene. In this report we demonstrate, through the construction of a long-range restriction map that links the flanking genetic markers GGG1 (D16S84) and 26.6PROX (D16S125), that the PKD1 gene lies within an extremely CpG-rich 750-kb segment of chromosome 16p13.3. Approximately 90% of this region has been cloned in three extensive cosmid/bacteriophage contigs. The cloned DNA is a valuable resource for identifying new closer flanking genetic markers and for isolating candidate genes from the region.

Chromosomes, Human, Pair 16↗
PubMed1992

FRA2B is distinct from inverted telomere repeat arrays at 2q13.

Human chromosome 2 was formed by a telomere-to-telomere fusion of two ancestral ape chromosomes. The fusion point is localized in chromosomal band 2q13, which also contains the rare, folate-sensitive fragile site FRA2B. It has been hypothesized that this fragile site may be related to the presence of interstitial telomeric and subtelomeric sequences, which have come to lie in an inverted repeat arrangement as a result of the fusion event. Fluorescence in situ hybridization of a genomic cosmid c8.1, which spans the fusion point, was carried out on metaphase spreads of an individual who expressed the fragile site at 2q13. We show that the fusion point maps distal to this fragile site. Therefore, we conclude that the inverted arrays of telomeric and subtelomeric sequences found at this fusion point are unlikely to correspond to the rare fragile site at 2q13.

Base Sequence↗