SYT4 and diabetes mellitus: In addition, given the information regarding the candidate genes for the ihs locus based on PubMed and MGI database, synaptotagmin 4 (Syt4), polycystic kidney disease 2 like 2 (Pkd2l2), receptor accessory protein 2 (Reep2), and endoplasmic reticulum chaperone SIL1 homolog (Sil1), which have been found involved in diabetes mellitus and/or insulin secretion, were the candidate genes for the ihs locus.