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AFP

Developmental stage

Occurs in the plasma of fetuses more than 4 weeks old, reaches the highest levels during the 12th-16th week of gestation, and drops to trace amounts after birth. The serum level in adults is usually less than 40 ng/ml. AFP occurs also at high levels in the plasma and ascitic fluid of adults with hepatoma.

Function

Binds copper, nickel, and fatty acids as well as, and bilirubin less well than, serum albumin. Only a small percentage (less than 2%) of the human AFP shows estrogen-binding properties.

Involvement in disease

Alpha-fetoprotein deficiency

AFPD

A benign condition characterized by undetectable AFP levels in the amniotic fluid. Affected individuals are asymptomatic and present normal development.

None

The disease is caused by variants affecting the gene represented in this entry.

Alpha-fetoprotein, hereditary persistence

HPAFP

A benign autosomal dominant condition characterized by continued expression of alpha-fetoprotein in adult life.

None

The disease is caused by variants affecting the gene represented in this entry.

Post-translational modifications

Independent studies suggest heterogeneity of the N-terminal sequence of the mature protein and of the cleavage site of the signal sequence.

Sulfated.

Sequence similarities

Belongs to the ALB/AFP/VDB family.

Tissue specificity

Plasma. Synthesized by the fetal liver and yolk sac.

Cellular localization

  • Secreted

Alternative names

  • Alpha-fetoprotein
  • Alpha-1-fetoprotein
  • Alpha-fetoglobulin
  • HPAFP
  • AFP

Target type

Proteins

Primary research area

Immuno-oncology

Molecular weight

68678Da