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R Dalgleish

Publications and source records attributed to R Dalgleish.

At least 37 records · Page 2Linked to original sources
PubMed1988

Linkage of a polymorphic marker for the type III collagen gene (COL3A1) to atypical autosomal dominant Ehlers-Danlos syndrome type IV in a large Belgian pedigree.

We have examined a large family in which eleven members have a form of autosomal dominant Ehlers-Danlos syndrome type IV. Analysis of fibroblast cultures from affected individuals showed a partial deficiency of type III collagen production. The protein produced was, however, normal in all aspects examined. Using a restriction site polymorphism associated with the structural gene for human type III collagen (COL3A1), we have found tight linkage between the low frequency polymorphic allele and the clinical expression of the disease (lod = 3.86 at 0 = 0), identifying the type III collagen gene as the disease locus.

Adult↗
PubMed1988

Collagen gene structure.

The collagens of vertebrates may be divided into three groups according to chain size and whether or not the helical domains are continuous. Present evidence suggests that, at least within one of these groups, similarity between collagens is reflected in the organization of the genes that encode them. Early evidence suggested that collagen genes evolved on the basis of exons which are multiples of a primordial building block of 54 bp, separated by much larger introns. This model of collagen gene evolution is contradicted by the recent discovery of a collagen gene with a single long open reading frame.

Animals↗
PubMed1988

Apparent monosomy 21 owing to a ring 21 chromosome: parental origin revealed by DNA analysis.

A three and a half year old mildly retarded boy is presented. Karyotyping showed monosomy 21 (45,XY,-21) in all 50 metaphase spreads examined from two lymphocyte cultures, and in 20% of cells examined from cultured fibroblasts; the remaining 80% of cells showed a ring 21 chromosome (46,XY,r(21)(p1q22]. Molecular studies using chromosome 21 specific DNA probes confirmed the monosomy in blood and showed that the ring 21 chromosome was paternal in origin. Parental karyotypes were normal.

Child, Preschool↗
PubMed1987

Segregation of all four major fibrillar collagen genes in the Marfan syndrome.

Linkage markers at or close to the genes encoding the three major fibrillar collagens were used to analyze the segregation of these loci in six pedigrees with dominantly inherited Marfan syndrome. Four pedigrees were discordant at one of the Type I collagen loci (COL1A2), and, of these, two were discordant at the other Type I locus (COL1A1). The Marfan syndrome also segregated independently of the structural loci for Type II and Type III collagen in these two families. This is evidence against the Marfan syndrome being, in general, due to mutations in the major fibrillar collagen genes.

Adolescent↗
PubMed1986

Human type III collagen gene expression is coordinately modulated with the type I collagen genes during fibroblast growth.

Type III collagen is one of the major interstitial collagens and, as such, plays an important role in modulating the structure and function of most tissues. To compare the expression of the type III collagen gene to that of the type I collagen alpha 1(I) and alpha 2(I) genes, cDNAs encoding the 3' one-third of the human alpha 1(III) collagen mRNA were obtained by screening a human fetal lung fibroblast cDNA library with a cloned segment of the chicken alpha 1(III) gene. Northern blot analysis of human fetal lung fibroblast RNA demonstrated two alpha 1(III)-specific mRNAs of sizes 6.6 and 5.8 kilobases, sizes clearly different from those of the type I collagen mRNAs. Analyses of populations of dividing and nondividing human lung fibroblasts revealed that, on a per cell basis, the nondividing population contained twice as much alpha 1(III) mRNA than did the dividing population. The same was true for the type I collagen alpha 1(I) and alpha 2(I) mRNA transcripts. Similar results were obtained when alpha 1(III), alpha 1(I), and alpha 2(I) mRNA transcripts were quantified by using dot blot evaluation of total RNA, Northern analysis of total RNA, and dot blot evaluation of cytoplasmic RNA. Thus, despite the fact that the alpha 1(III) collagen gene is located on a chromosome different from the alpha 1(I) and alpha 2(I) genes, the expression of these three collagen chains appears to be coordinately controlled during periods of rapid and slow fibroblast growth.

Amino Acid Sequence↗
PubMed1986

Length polymorphism in the pro alpha 2(I) collagen gene: an alternative explanation in a case of Marfan syndrome.

A 38 base pair (bp) insertion in the pro alpha 2(I) collagen gene (COL1A2) of a patient with Marfan syndrome has been proposed to be the possible cause of the disease (Henke et al. 1985). However, analysis of this insertion in DNA from the patient in question and from random normal individuals reveals it to be a common polymorphism. We suggest that the 38 bp insertion is not related to the primary defect in this case of Marfan syndrome.

Base Sequence↗
PubMed1985

Chromosomal assignments of the genes coding for human types II, III, and IV collagen: a dispersed gene family.

The human type II collagen gene, COL2A1, has been assigned to chromosome 12, the type III gene, COL3A1, to chromosome 2, and one of the type IV genes, COL4A1, to chromosome 13. These assignments were made by using cloned genes as probes on Southern blots of DNA from a panel of mouse/human somatic cell hybrids. The two genes of type I collagen, COL1A1 and COL2A1, have been mapped previously to chromosomes 17 and 7, respectively. This family of conserved genes seems therefore to be dispersed throughout the genome.

Animals↗
PubMed1985

Polymorphism of DNA sequence in the human pro alpha 2(I) collagen gene.

The human pro alpha 2(I) collagen gene was analysed for the presence of restriction fragment length polymorphisms. DNA from randomly selected unrelated persons of three Southern African populations was cleaved with one of eight different restriction enzymes, electrophoresed, blotted, and hybridised with cDNA and genomic probes specific for the pro alpha 2(I) gene. An MspI polymorphism was detected which results from the loss of a cleavage site within the 3' half of the gene. In two of the populations studied, the polymorphism occurred at significant frequencies, and should therefore prove useful as a genetic marker for the study of inherited disorders of connective tissue involving collagen structure or biosynthesis.

Chromosome Mapping↗
PubMed1982

Copy number of a human type I alpha 2 collagen gene.

HpCl, a Charon 4A bacteriophage containing a 16.3-kilobase insert of human genomic DNA, has been identified as representing the 3' portion of the human alpha 2(I) collagen gene by hybrid selected translation and cross-reactivity with characterized sheep and chick collagen genes. Evaluation of HpCl by restriction endonuclease mapping and alpha 2(I) mRNA hybridization demonstrated that the alpha 2(I) mRNA coding regions are separated by noncoding regions including one of 2.7 kilobase pairs near the 3' end of the mRNA coding region. In addition, a 1.8-kilobase XbaI-BamHI fragment containing the 2' a 1.8-kilobase XbaI-BamHI fragment containing the 3' end of the alpha 2(I) mRNA coding region includes a region of DNA that is repeated many times throughout the human genome. Quantification of alpha 2(I) gene number, using the technique of DNA dot hybridization, with two EcoRI fragments from HpClo as probes, demonstrated that HpCl is represented once in the human genome. In this context, it is unlikely that human alpha 2(I) collagen chain production is modulated by differential transcription of multiple alpha 2(I) genes.

Animals↗
PubMed1977

Immunoglobulin levels in white and metis communities in Saskatchewan.

Serum-immunoglobulin levels (IgG, IgM, IgA, IgD, IgE) have been studied in white and metis (Cree Indian) communities in Saskatchewan. The levels of IgG, IgA, IgD and IgE were higher in the metis than in the whites. Both IgG and IgM were higher in females than in males. IgG and IgA levels rose progressively with age. IgM levels rose rapidly during the first year to almost adult levels, and then fell gradually after the age of 30. IgE levels also rose rapidly during the first 3 years of life, were higher on average in children than in adults, and fell to adult levels at puberty. Low levels of IgA were associated with high levels of IgG; they were not associated with either high levels of IgE or an increase in the prevalence of asthma.

Adolescent↗
PubMed1976

The divergence between human and baboon globin genes.

Complementary DNA (cDNA) was prepared with viral RNA-directed DNA polymerase from purified baboon globin messenger RNA (mRNA). Homologous and heterologous hybrids between human and baboon mRNAs and cDNAs were compared for extent of hybridisation and thermal stability. Higher mRNA inputs to the hybridizations were required to reach saturation in the heterologous cases. The melting temperature of the heterologous hybrid was 5 degrees C lower than the homologous hybrid. Between these two primates, divergence has occurred in the globin gene to a smaller extent than that possible from third position changes in the coding sequences of the divergence of total DNA. Globin cDNA prepared from baboon will not in general be useful as a probe for human globin mRNA or human globin gene sequences.

Animals↗