Summary
The proband, a 76-year-old woman, suffered from dural arteriovenous fistula. Her plasma
histidine-rich glycoprotein (HRG) level was 50% of the normal level. A low level of
plasma HRG was also found in her third daughter. A single nucleotide substitution
of T to C was found at nucleotide position 11,438 in exon 6 of the HRG gene from the
proband, converting Cys223 to Arg in the second cystatin-like domain. The same mutation
was also identified in her third daughter, but not in the other four family members
having normal HRG levels or in 50 unrelated healthy Japanese individuals. Expression
studies in BHK cells showed that substantial intracellular degradation of the mutant
occurred and only about 40% of the recombinant HRG mutant was secreted. These results
indicate that congenital HRG deficiency caused by a substitution of Cys223 to Arg
is hereditary in this family.
Key words
Congenital histidine-rich glycoprotein deficiency - histidine-rich glycoprotein -
thrombosis