Identification of eight point mutations in protein S deficiency type I--analysis of 15 pedigrees.
We described molecular genetic studies of 15 patients with protein S deficiency type I (i.e. reduced total protein S antigen). All the exons of the PROS 1 gene were analyzed both by PCR and direct sequencing in all 15 probands. This analysis led to the identification of point mutations affecting eight individuals. One of these mutations (codon-25, insertion of T) has been described previously in a Dutch pedigree. The other mutations are novel and all are located in exons that code for the protein S domain that is homologous to the steroid hormone binding globulins. They include two amino acid replacements (one individual with 340 Gly--> Val, and two individuals with 467 Val --> Gly), and four frameshift mutations due to either one bp deletions (in codon 261 deletion of T and in codon 267 deletion of G) or insertions (in codon 565 insertion T and after codon 578 insertions of C). Studies performed in six families (totalling 43 subjects) showed cosegregation of the genetic abnormality with reduced plasma protein S levels, and provided genetic evidence for a heterozygous protein S deficiency in 25 of them. The yield of mutations in this study (53%) confirms that the percentage of protein S deficient cases in which a point mutation is found remains low.
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003062:Codon / Q000235:genetics; D004252:DNA Mutational Analysis; D005091:Exons; D005260:Female; D005796:Genes; D020022:Genetic Predisposition to Disease; D005820:Genetic Testing; D006801:Humans; D008297:Male; D008322:Mammals / Q000235:genetics; D008969:Molecular Sequence Data; D010375:Pedigree; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D017293:Protein S / Q000737:chemistry / Q000235:genetics*; D018455:Protein S Deficiency / Q000235:genetics*; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity; D013927:Thrombosis / Q000209:etiology
D003062:Codon; D017293:Protein S