C4B and asthma: CH variants in ATP2C2 are associated with an increased risk of chronic obstructive pulmonary disease (COPD) (p = 0.000238), and CH variants in FLG are associated with an increased risk of asthma (p = 0.002174), while CH variants in USH2A are associated with an increased risk of visual impairment and blindness (p = 0.000307) (Figure 3B).