Library.

“Leucine zipper EF-hand-containing transmembrane protein 1 (LETM1) was initially identified through studies investigating the genetic basis of Wolf–Hirschhorn syndrome (WHS).”

The historical record supports this claim. LETM1 was first identified in gene-mapping and positional-cloning studies of the 4p16.3 region associated with Wolf–Hirschhorn syndrome, aimed at finding genes deleted in affected patients. A more precise wording would mention mapping of the WHS critical region, but the claim’s core point remains accurate.

“LETM1 is a proton-coupled mitochondrial calcium transport pathway that complements the mitochondrial calcium uniporter (MCU) and the sodium/calcium/lithium exchanger (NCLX) in controlling mitochondrial Ca2+ dynamics.”

The claim is well supported in its narrower form. Current evidence indicates LETM1 can mediate proton-coupled mitochondrial Ca2+ transport and contributes to Ca2+ handling alongside MCU and NCLX. The main caveat is that newer literature often assigns the primary bulk Ca2+/H+ exchanger role in mammals to TMBIM5, making LETM1 better described as complementary or regulatory than dominant.