Kallikreins are a subgroup of serine proteases having
diverse physiological functions. Growing evidence suggests that
many kallikreins are implicated in carcinogenesis and some have
potential as novel cancer and other disease biomarkers. This gene
is one of the fifteen kallikrein subfamily members located in a
cluster on chromosome 19. Its protein product is a protease present
in seminal plasma. It is thought to function normally in the
liquefaction of seminal coagulum, presumably by hydrolysis of the
high molecular mass seminal vesicle protein. Serum level of this
protein, called PSA in the clinical setting, is useful in the
diagnosis and monitoring of prostatic carcinoma. Alternate splicing
of this gene generates several transcript variants encoding
different isoforms.