Hypotonia-Cystinuria Syndrome, also known as cystinuria with mitochondrial disease, is related to 2p21 microdeletion syndrome without cystinuria and hypotonia. An important gene associated with Hypotonia-Cystinuria Syndrome is DEL2P21 (Hypotonia-Cystinuria Syndrome), and among its related pathways/superpathways are Primary ovarian insufficiency and Defective SLC3A1 causes cystinuria (CSNU). The drugs Sulfamethoxazole and Anti-Infective Agents have been mentioned in the context of this disorder. Affiliated tissues include brain, and related phenotypes are failure to thrive and frontal bossing