Low RFI (high efficient) steers had the lower proportion of beneficial FAs such as 18:2n-6, total n-6, PUFA, and t11-18:1 and c9, t11-CLA, as well as the higher unhealthy FAs (i.e. 16:0) in subcutaneous tissue, especially within KC breed. The gene discussed is SELPLG; the disease is keratoconus.