Our results suggest that the absolute effect of tBCAAs/glycine ratio, defined with instruments with a P-gain >10, on hypertension or CHD is significantly stronger compared with the individual absolute effects of glycine and tBCAAs, and this observation holds after the exclusion of a CPS1 instrument, which is characterized by sex-specific effects,18 and thus may additionally influence MR results. The gene discussed is CPS1; the disease is Hypertension.