| Modification Notes |
SPNS3 (spinster homolog 3) is a 512 amino acid multi-pass membrane protein that belongs to the spinster subfamily of major facilitator proteins and functions as a sphingolipid transporter. SPNS3 is produced as multiple alternatively spliced isoforms that are encoded by a gene which maps to human chromosome 17; a chromosome that comprises nearly 2.5% of the human genome and encodes over 1,200 genes. Two key tumor suppressor genes are associated with chromosome 17, namely, p53 and BRCA1. Tumor suppressor p53 is necessary for maintenance of cellular genetic integrity by moderating cell fate through DNA repair versus cell death. Malfunction or loss of p53 expression is associated with malignant cell growth and Li-Fraumeni syndrome. Like p53, BRCA1 is directly involved in DNA repair, though specifically it is recognized as a genetic determinant of early onset breast cancer and predisposition to cancers of the ovary, colon, prostate gland and fallopian tubes. |