Aim: The purpose of this study was to examine the expression pattern of <i>GAS5</i> lncRNA in plasma samples of MM patients and to evaluate its clinical and prognostic significance.<h4>Methods and material</h4>73 newly diagnosed patients with MM and 16 healthy volunteers were recruited from Clinical Hospital Centre (CHC) "Bežanijska Kosa" and CHC "Zemun" in the period from July 2020 to December 2024. The gene discussed is GAS5; the disease is Miyoshi myopathy.