Mutations in the fibrinogen Bβ-chain gene identified in the 2 afibrinogenemic patients.

Donor splice site consensus sequence16 (top) and partial fibrinogen Bβ-chain gene sequence showing the position of the identified mutations (IVS6 + 13C > T and IVS7 + 1G > T) (bottom) are shown. The genomic Bβ-chain sequence spans from nucleotide positions 6600 to 7299. Identified mutations are indicated by an arrow. Exonic sequences are in uppercase letters and shaded in gray, whereas intronic sequences are in lowercase letters. Physiologic donor splice sites are boxed; the cryptic donor splice site in intron 6 is double-boxed. The invariant GT dinucleotide of the donor splice site is in boldface.