It encodes an RNA-binding protein which is more similar to Drosophila Boule than to human proteins encoded by genes DAZ (deleted in azoospermia) or DAZL (deleted in azoospermia-like).

Loss of this gene function results in the absence of sperm in semen (azoospermia).

Histological studies demonstrated that the primary defect is at the meiotic G2 / M transition in fruitfly but in mice the primary defect is postmeiotic at round spermatid stage.

[8] Multiple alternatively spliced transcript variants encoding distinct isoforms have been found for this gene.

[7][9] The boule-like protein appears to be ubiquitously expressed in males of all animal species, except in the most primitive trichoplax.