Recently, a few mutations in gene for the prolyl hydroxylase domain 2 protein (PHD2) have been reported in cases of congenital erythrocytosisnot associated with tumor formation with the exception of one patient with a recurrent extra-adrenal paraganglioma.
The variants display differential effects on catalytic rate and substrate binding, implying that partial inhibition or selective inhibition with regard to HIFalpha isoforms of PHD2 could result in the phenotype displayed by patients with familial erythrocytosis.
Recently, a missense mutation [c.950C>G (p.Pro317Arg)] in the prolyl hydroxylase domain protein 2 (PHD2) gene, whose encoded protein has HIF-1alpha as a substrate, provided evidence of the PHD2 role in a case of familial erythrocytosis.
A recent report of familial erythrocytosis now implicates a different protein, Prolyl Hydroxylase Domain protein 2 (PHD2), which is an enzyme that hydroxylates HIF.
We show that this mutation in PHD2 results in a marked decrease in enzyme activity and is associated with familial erythrocytosis, identifying a previously unrecognized cause of this condition.