Also IGF binding protein 5 (IGFBP5) mRNA expression is significantly increased in both HF64 and DM66 patients, indicating supressed anabolic signalling as IGFBP5 can inhibit IGF‐1 signalling and thus mTORC1 activation,74 while lower levels of serum IGFBP3 alongside evidence of growth hormone resistance have been reported in HF patients.75 This evidence concerns the gene IGFBP5 and hydrops fetalis.