Mutations of the ANLN gene have been linked to functional or structural renal anomalies; those of the POU6F2 gene are associated with susceptibility to Wilms tumor (MIM# 601583); mutations of the GCK gene cause MODY II diabetes; pathogenic variants of the CCM2 gene cause cavernous cerebral malformation; and those of the IKZF1 gene result in immunodefficiency, providing a reason for close follow-up and screening for comorbidities in our patient. The gene discussed is CCM2; the disease is Wilms tumor.