F9 and hemoglobin measurement: Up to November 2018, the F9 gene mutation database (EAHD Coagulation Factor Variant Databases) has recorded a total of 1094 mutations in 3713 HB patients [7], more than 3940 unique mutations have been reported so far in HGMD, 2020 [6]; point mutations accounts for 73.1% and mutations within the serine protease domain (SPD) account for about 56.1% among different populations [5, 8–17].