Familial early-onset deep venous thrombosis associated with a novel HRG mutation.

Deep venous thrombosis (DVT) remains a serious clinical problem that affects millions of people worldwide. Some DVT cases are caused by inherited thrombophilia derived from genetic aberrations and several disease-causing genes have been identified so far. Among them, HRG is an uncommon one with limited related reports. Here, we reported on a family with early-onset DVT where acquired risky conditions were excluded. Whole exome sequencing revealed a novel heterozygous single base pair substitution in exon 2 of HRG gene resulting in a conserved residue replacement of the protein (c. C271T, p. P73S). Sanger sequencing confirmed the co-segregation of the mutation and plasma quantification determined circulating protein deficiency. The mutation might therefore impair hemostatic balance by causing reduced circulating HRG level. Our study broadens the mutation spectrum of the HRG gene and underscores the importance of its function in regulating coagulation pathway.