Table 1.

SLC48 and SLC49 heme and FLVCR1-related transporter families

Human gene name	Prote in name	Aliases	Predomina nt substrates	Transport type/coupli ng ions	Tissue distribution and cellular/subcellul ar expression	Link to disease	Human gene locus	Sequence accession ID	Splice variants and their specific feautres
SLC49A 1	FLVCR 1	FLVCR, MFSD7B, AXPC1, PCARP	Heme	unknown	Ubiquitous, high expression in intestine, liver, kidney, brain and bone marrow. Located on the plasma membrane.	Posterior column ataxia and retinitis pigmentos a (PCARP) syndrome , Diamond- Blackfan anemia (DBA).	1q32.3	NM_014053	Four splice variants observed in DBA, lacking exon 2 or 3 ± exon 6, an additional splice variant lacking exon 6 seen in both control and DBA erythroid cells.
SLC49A 2	FLVCR 2	MFSD7C, CCT, EPV, PVHH, FLVCRL1 4q	Heme	unknown	Liver, kidney, brain, lung, placenta, fetal liver, bone marrow. Located on the plasma membrane.	Fowler syndrome	14q24.3	NM_017791.2 NM_001195283 .1	A variant transcript differs in the 5′-UTR and uses an alternate start codon, which should encode a shorter hypothetical protein.
SLC49A 3	MFSD7	LP2561, FLJ22269	unknown	unknown	Pancreas, spleen, brain, lung, ovary, breast.	Ovarian cancer	4p16.3	NM_032219.2	Isoforms differ from the canonical sequence as follows: Isoform #2: aa 242 missing. Isoform #3: aa 46-67 and 99-195 missing. Note: No experimenta l confirmation of these isoforms.
SLC49A 4	DIRC2	RCC4, FLJ14784	unknown	unknown	Pancreas, kidney, liver, placenta, heart. Predominantly localizes to the lysosome.	Renal cell and prostate cancers.	3q21.1	NM_032839.2	Isoform #2 differs from the canonical sequence as follows: aa 380-411: alternative sequence and aa 412- 478: missing. Note: No experimenta l confirmation .
SLC48A 1	HRG-1		Heme	C/H+?	Liver, heart, CNS, kidney, skeletal muscle, small intestine. Localizes predominantly to the endosome, also observed on the cell surface when overexpressed.		12q13.1 1	NM_017842	Two isoforms differ in the length of the 3′-UTR. Short form is predominant ly expressed.