The function of SLC44A1 (solute carrier family 44 member 1, ENSG00000070214) is as follows. Choline/H+ antiporter (PubMed:19357133, PubMed:23651124, PubMed:31855247, PubMed:33789160). Also acts as a high-affinity ethanolamine/H+ antiporter, regulating the supply of extracellular ethanolamine (Etn) for the CDP-Etn pathway, redistribute intracellular Etn and balance the CDP-Cho and CDP-Etn arms of the Kennedy pathway (PubMed:33789160). Involved in membrane synthesis and myelin production (PubMed:31855247). {ECO:0000269|PubMed:19357133, ECO:0000269|PubMed:23651124, ECO:0000269|PubMed:31855247, ECO:0000269|PubMed:33789160}.