Novel mutations in the factor VII gene of Taiwanese factor VII-deficient patients

The genetic defects of four Taiwanese patients with factor VII (FVII) defic iency were studied. FVII activity and antigen levels were <1 u/dl and 125.7 u/dl (patient 1). < 1 u/df and < 1 u/dl (patient II), 3.4 u/dl and 5.9 u/d l (patient III), and 1.2 u/dl and 30.4 u/dl (patient IV) respectively. The 5' flanking region. and all exons and junctions were amplified using polyme rase chain reaction and sequenced. Patient I was homozygous for a 10824C -- > A transversion with Pro(303)-->Thr mutation in exon 8, In patient II, a h eterozygous transversion, 9007+1G-->T at the IVS6, a heterozygous decanucle otide insertion polymorphism at -323 (both mutations present in his father) and a heterozygous deletion, del TC (26-27) in exon 1A (originating from h is mother) were identified. Patient III had a homozygous 10961T-->G transve rsion with His(348)-->Gln mutation in exon 8, Patient IV had a heterozygous 10902T-->G transversion with Cys(329)-->Gly mutation in exon 8 (transmitte d to her second son) and a heterozygous decanucleotide insertion polymorphi sm at -323 (transmitted to her third son). All but one of the FVII gene mut ations detected in the four patients have not been previously reported. In conclusion, four novel mutations of the FVII gene in Taiwanese, including t wo missense mutations in exon 8, one point mutation at the exon 6 splice si te and one deletion in exon 1A, were identified.