P4HA1 is a symbol for the gene, Prolyl 4-hydroxylase, alpha polypeptide I, in humans. Other names include: Prolyl 4-hydroxylase subunit alpha-1; 4-PH alpha-1; Procollagen-proline,2-oxoglutarate-4-dioxygenase subunit alpha-1; collagen prolyl 4-hydroxylase alpha(I); P4HA. The encoded protein is an enzyme with an amino acid length of 534 and a mass of 61.0 kDa. P4HA1 is a member of the P4HA family. This gene shares homology with other species, including: Mouse, Rat, Zebrafish, Frog, Chicken.