The function of MFSD14A and MFSD14B is unclear, however, MFSD14A has been linked to infertility in male mice due to a marked reduction of spermatozoa possibly due to faulty glycosylation (Doran et al., 2016), and both have been found to be intracellular proteins most located to the Golgi and endoplasmic reticulum, respectively (Lekholm et al., 2017). The gene discussed is SLC71A1; the disease is Infertility.