SLC30A4 and zinc deficiency, transient neonatal: One report has also suggested the involvement of ZNT5-ZNT6 heterodimers in the pathogenesis of TNZD [132], but there are no reports indicating that low-zinc breast milk can be attributed to mutations in the ZNT4 gene in humans, although Znt4 is involved in low-zinc breast milk in mice [97,98].