Combined protein C and protein S deficiency in a family with repetitive thromboembolism and segregated gene mutations.

A young man with repetitive deep venous thrombosis of the legs and the inferior vena cava, and his family were eventually diagnosed by means of molecular genetic analysis as having both hereditary protein C and protein S deficiency. There have been a few reports of families with combined protein C and protein S deficiency and only one report of such a family characterized at the DNA level. This was the first reported family in Japan with combined deficiency of protein C and protein S accompanied by segregation of gene lesions.