Beyond conventional biomarkers, such as NfL and progranulin (PGRN), glycolipid and sphingolipid profiling via MS provide mechanistic insight into membrane biology and neuronal–glial interactions and lipid-mediated signaling.The ability to detect these lipid alterations in peripheral biofluids through MS expands the potential for minimally invasive biomarkers and precision medicine approaches in FTD and related syndromes [22,119,120]. The gene discussed is GRN; the disease is frontotemporal dementia.