Characterization of the human prostaglandin H synthase 1 gene (PTGS1): exclusion by genetic linkage analysis as a second modifier gene in familial thrombosis

Abstract

Genetic evidence from a large Vermont kindred indicates that an unknown gene promotes thrombosis when inherited in conjunction with type I protein C deficiency. Cyclooxygenase-1 [prostaglandin H synthase 1 gene (PTGS1)] was tested as a plausible candidate for the unknown gene because of its role in primary hemostasis. The complete sequence of PTGS1 (25 638 nucleotides) was determined from a 37 kb human genomic cosmid clone to characterize intronic regions and subsequently to allow the search for mutations by direct sequencing of genomic DNA. Northern blot analysis confirms usage of a newly described distal poly-adenylation signal. Short tandem repeat (STR) sequences found in intron 2 and the 3' flanking region were developed as new genetic markers for PTGS1. The position of PTGS1 was refined on the CHLC chromosome 9 linkage map using the new markers scored in four Centre d'Etude du Polymorphisme Humain families and multipoint linkage analysis. Direct sequencing of DNA from members of the Vermont kindred led to the discovery of two new single nucleotide polymorphisms (SNPs) that give rise to non-conservative amino acid changes in the signal peptide (Arg(8) to Trp and Pro(17) to Leu) of cyclooxygenase-1. Linkage analysis of the SNP and STR markers indicated that PTGS1 is not the interacting gene associated with an increased incidence of thrombosis in the Vermont kindred.

COX2 in a euryhaline teleost,Fundulus heteroclitus: primary sequence, distribution, localization, and potential function in gills during salinity acclimation

“…high melting temperature). To minimize the chance of amplifying contaminating genomic DNA, the primer pair was designed to include at least one intron-exon boundary that is conserved between vertebrate COX homologues (Hla and Neilson, 1992;Kosaka et al, 1994;Scott et al, 2002). A QuantumRNA™ 18S internal standard primer kit (Ambion, Woodward Austin, TX, USA) was used to control for variability in RNA quality and quantity between the different tissues tested.…”

Identification and functional characterization of polymorphisms in human cyclooxygenase-1 (PTGS1)

“…In contrast, characterization of genetic variation in PTGS1 has not been as widely investigated, even though the presence of functionally relevant variants may significantly influence PG biosynthesis, disease risk, and NSAID pharmacodynamics in humans. Polymorphisms in both coding and noncoding regions of human PTGS1 have been previously identified [10][11][12][13], and PTGS1 has been resequenced as part of the Seattle SNPs Variation Discovery Resource (http:// pga.mbt.washington.edu/). In particular, nonsynonymous variants encoding amino-acid substitutions in the COX-1 protein have been identified [10][11][12][13].…”

“…Polymorphisms in both coding and noncoding regions of human PTGS1 have been previously identified [10][11][12][13], and PTGS1 has been resequenced as part of the Seattle SNPs Variation Discovery Resource (http:// pga.mbt.washington.edu/). In particular, nonsynonymous variants encoding amino-acid substitutions in the COX-1 protein have been identified [10][11][12][13]. The functional consequences of these variants, in terms of their influence on basal COX-1-mediated arachidonic acid metabolism, however, have not been characterized to date.…”

A review of gene-drug interactions for nonsteroidal anti-inflammatory drug use in preventing colorectal neoplasia

“…However, this polymorphism has been reported to be in complete linkage disequilibrium with a promoter polymorphism, À842A4G, which may affect binding of transcription factors. 56 The Pro17Leu variant has been associated with altered prostaglandin production 57 and coxib selectivity. 54 No statistically significant interactions have been reported for the Arg8Trp, Leu15-16del or Leu237Met polymorphisms.…”