FLCN and kidney neoplasm: BHD mRNA is expressed in a variety of tissues including stromal cells, the distal nephron of the kidney, type I pneumocytes of the lung, and skin and its appendages.23 However, reduced expression of BHD was seen in renal tumours from patients with BHDS,23 consistent with the reported inactivation of the wild-type BHD allele by somatic mutation or LOH in BHD associated renal tumours.24