Factor VIII mutations in 42 Moldovan haemophilia A families, including 12 that are novel

Abstract

Haemophilia A (HA) is a bleeding disorder caused by mutations within the X-linked F8 gene. A series of 42 unrelated Moldovan patients with HA had their disease-causative mutation determined to provide clinically valuable genotyping information for a historically underserved population and to utilize factor VIII (FVIII) structural information to analyse the effects of haemophilic missense substitutions. DNA samples were analysed to detect intron 22 and intron 1 inversions followed by heteroduplex analysis of PCR-amplified fragments containing all exonic sequences. Missense sites identified by DNA sequencing were visualized in the recently described crystal structures of human FVIII. Of the 26 different point mutations, 12 were novel. Gel electrophoresis identified samples with a second major DNA band that migrated abnormally; these amplified products were sequenced. Thirteen intron 22 inversions and one intron 1 inversion were found. Two patients had large, partial gene deletions and there were six frameshift, two non-sense, two splicing and 16 missense genotypes. Two subjects with an intron 22 inversion and one with a large, partial gene deletion developed an alloimmune inhibitor. Their localization suggests intra- and possibly inter-molecular interactions that are important for the structural integrity and/or procoagulant function of FVIII.

Factor VIII gene mutations profile in 148 Chinese hemophilia A subjects

“…Apart from the intron 22 and one inversions, 67 different mutations were detected, including 33 missense mutations and 34 other mutations. Among the 67 detected FVIII mutations, 35 (52%) had not been reported in HAMSTeRS mutation database or recent articles published after the last update of HAMSTeRS database (6–8, 17–22). In addition, three severe subjects were not found with any mutations in this study.…”