TET2 and myeloproliferative neoplasm: Previously, we noted that the frequency of rs3733609 C/T genotype (located in TET2 exon 9)(http://www.ncbi.nlm.nih.gov/snp/?term = rs3733609) was much higher in one familial PMF than sporadic PMF (unpublished data), suggesting rs3733609 may be a MPN predisposition allele.