Putative CLN3 promoters have been pulled down by gene‐wide chromatin immunoprecipitation of MITF. One form of LF is secreted in body fluids (sLF) whereas an alternative form deltal LF, regulated by a different promoter, is present in normal tissues. Delta LF is downregulated in breast cancer. CLN3 is downregulated in delta LF expressing cell's.promoter. This evidence concerns the gene CLN3 and breast carcinoma.