AFRICAN-AMERICAN FACTOR VII-DEFICIENT VARIANTS IN GEORGIA (FVII VARIANTS)

We studied African-American Factor (FVII)-deficient variants and carri ers in Georgia by measuring their levels of FVII antigen (FVIIAG) and FVII procoagulant (FVIIC). Factor VIIAG was determined using enzyme-li nked immunoassay (ELISA), whereas FVIIC was measured in two ways: 1) b y fibrin clotting methods that employed human recombinant (HRFVIIC), h uman placental(HPFVIIC), rabbit brain (RBFVIIC), and bovine brain (BBF VIIC) thromboplastins; and 2) by an amidolytic method (AMFVIIC). Proth rombin time tests (PT) were also performed by standard methods. These 4 FVII-deficient patients and 3 carriers demonstrated the following re sults: PT: 18.2 +/- 6.5 sec; FVIIAG: 73.0 +/- 14.9%; HRFVIIC: 30.6 +/- 20.3%; HPFVIIC: 30.5 +/- 21.4%; RBFVIIC: 25.3 +/- 21.4%; BBFVIIC: 30. 6 +/- 17.5%; AMFVIIC: 44.1 +/- 18.3%. We conclude that a group of clin ically mild African-American FVII-deficient variants exists in Georgia . This group is characterized by the presence of FVIIAG and decreased FVIIC, using a variety of thromboplastins; an excellent correlation wa s noted for both human thromboplastins. (C) 1994 Wiley-Liss, Inc.