FOXL2: a gene central to ovarian function

Abstract

TheFOXL2(forkhead box L2) gene is located on chromosome 3 and encodes for forkhead box (FOX) family of transcription factors which play a critical role in various biological processes. GermlineFOXL2mutations have been identified in blepharophimosis/ptosis/epicanthus inversus syndrome. The somatic missense mutation inFOXL2(FOXL2C134W) is now known to be the defining molecular feature of adult-type granulosa cell tumour of the ovary, present in over 90% of cases of this tumour type. Immunohistochemistry forFOXL2is used as a marker of sex cord-stromal differentiation. However, expression is not restricted to lesions harbouringFOXL2mutations, and it is positive in a variety of sex cord-stromal proliferations other than adult-type granulosa cell tumour.