TBX5 and chronic obstructive pulmonary disease: To illustrate this point, we highlight two genes: TBX5, a gene directly linked to cardiac arrhythmia (Figure 6D) (Smemo et al., 2012; Arnolds et al., 2012), and LITAF, a gene that, until recently, had no obvious role in cardiac biology (Moshal et al., 2017) (Figure 6E).