Human histidine-rich glycoprotein gene: evidence for evolutionary relatedness to cystatin supergene family.

The human chromosomal histidine-rich glycoprotein (HRG) gene has been isolated and its molecular structure was partially characterized. The gene is approximately 11 kb in length and contains nine exons and eight introns. Locations of the introns in HRG gene coding for cystatin domains are essentially identical with those of cystatin SN, SA and C, and kininogen genes. These results provide direct evidence that HRG belongs to a supergene family that includes cystatin SN, SA and C, and kininogen, and also demonstrate high conservation of the intron-exon organization among this supergene family.