The human genome produces a large repertoire of non-coding RNAs (ncRNAs) with important regulatory roles in development, physiology, and most of diseases. Among these, long non-coding RNAs (lncRNAs) have emerged as key modulators of gene expression, chromatin organization, and cellular homeostasis, despite displaying remarkably low primary-sequence conservation across species. This apparent evolutionary paradox questions the limitations of predicting biological function based on conservation, particularly across different biological domains. Here, we examine current evidence on lncRNA evolution, with a focus on their roles in metabolic regulation compared with neurobiological processes. We hypothesize that lncRNAs involved in ancient and conserved pathways such as metabolism may be under stronger evolutionary constraint than those associated with higher-order, species-specific traits, although available data support a more nuanced interpretation. Functional importance often correlates poorly with linear sequence conservation and instead appears to depend on higher-level features, including RNA secondary or tertiary structure, genomic context, regulatory architecture, and interactions with conserved molecular partners. We propose a systematic comparative framework to empirically assess conservation among metabolism- and neuro-associated lncRNAs using phylogenetic, syntenic, structural, and expression-based metrics. Finally, we discuss the therapeutic implications of lncRNA biology, highlighting how a deeper understanding of their evolutionary and mechanistic properties may inform the development of more precise and effective RNA-targeting strategies. Together, these insights underscore the non-coding transcriptome as a critical frontier for both fundamental biology and precision medicine.
Metzinger et al. (Sat,) studied this question.