For instance, the glucocerebrosidase gene (GBA), a major genetic risk factor for Parkinson’s disease, also shows significant associations with blood measurements and inflammatory markers (e.g. haemoglobin concentration and C-reactive protein), the circulatory system (e.g. cardiac arrhythmias); endocrine, nutritional and metabolic diseases (e.g. disorders of sphingolipid metabolism and other lipid storage disorders), and body measurements (e.g. body mass index), indicating substantial pleiotropy. Here, GBA1 is linked to cardiac arrhythmia.