has material basis in germline mutation in LTC4S hypotonia-failure to thrive-microcephaly syndrome https://github.com/monarch-initiative/mondo/issues/9602 https://www.malacards.org/card/leukotriene_c4_synthase_deficiency UMLS:C3279662 leukotriene C4 synthase deficiency LTC4 synthase deficiency MESH:C565439 OMIM:614037 GARD:0016725 Orphanet:79507 MEDGEN:481292 SCTID:717185008 Leukotriene C4 synthase deficiency is an extremely rare fatal neurometabolic developmental disorder characterized clinically by muscular hypotonia, psychomotor retardation, failure to thrive, and microcephaly. MONDO:0013539 inborn errors of metabolism