Genetic basis underlying the low VWF subgroups and type 2A/B/M VWD. (A) Presence of likely pathogenic VWF sequence variants among patients with low VWF with VWF:GPIbM/VWF:Ag ratios of ≥0.7 (n = 48) and <0.7 (n = 10), and among those with type 2A/2B/2M VWD (n = 228). The P values were determined using χ2 tests. (B) Illustration of the likely pathogenic VWF sequence variants identified in patients with low VWF with VWF:GPIbM/VWF:Ag ratios of <0.7 (above the VWF monomer) in comparison with those among patients with type 2A/2B/2M VWD (below the VWF monomer). Some variants were present in >1 patient. (C) Illustration of the likely pathogenic VWF sequence variants identified among patients with low VWF with VWF:GPIbM/VWF:Ag ratios of ≥0.7 (above the VWF monomer) in comparison with those among patients with VWF:GPIbM/VWF:Ag ratios of <0.7 (below the VWF monomer). The red variants were present in both groups. Some variants were present in >1 patient. An asterisk indicates a variant with a stop codon.
