ART4 and sarcopenia: On the other hand, Mendelian Randomization Analysis revealed five other plasma proteins—leukocyte immunoglobulin-like receptor subfamily B subfamily member 2 (LILRB2), asporin (ASPN), contactin-2 (CNTN2), ecto-ADP-ribosyltransferase 4 (ART4), and superoxide dismutase 2 (SOD2)—that may be associated with sarcopenia and could represent new targets in the manufacture of drugs for this disorder.