Among all patients with MPRT in Groups A and B and a specified genetic cause (n = 469), the most common reported causes were VHL disease (69.7%), Birt-Hogg-Dubé (BHD) syndrome (14.2%), HPRC (MET variants) (4.7%), tuberous sclerosis complex (TSC) (6.5%), hereditary leiomyomatosis and renal cell cancer syndrome (HLRCC) (2.4%), succinate dehydrogenase (SDH) deficiency (1.5%) and a constitutional translocation (1.1%). The gene discussed is SDHB; the disease is hereditary leiomyomatosis and renal cell cancer.