CHRM2 and COVID-19: According to the study by Wallukat et al. [57], patients with the symptoms mostly of neurological origin (including post-COVID-19 fatigue, attention deficit, tremor and others) were positive for antibodies to chronotropic GPCR-fAABs targeting the β2-adrenoceptor, the α1-adrenoceptor, the angiotensin II AT1-receptor, and the nociception-like opioid receptor and negative to chronotropic GPCR-fAABs targeting the muscarinic M2-receptor, the MAS-receptor, and the ETA-receptor, which are also found in POTS and dysautonomia [58].