F8A1

Factor VIII intron 22 protein is a protein that in humans is encoded by the F8A1 gene.

This gene is contained entirely within intron 22 of the factor VIII gene; spans less than 2 kb, and is transcribed in the direction opposite of factor VIII. A portion of intron 22 (int22h), containing F8A, is repeated twice extragenically closer to the Xq telomere. Although its function is unknown, the observation that this gene is conserved in the mouse implies it has some function. Unlike factor VIII, this gene is transcribed abundantly in a wide variety of cell types.