The function of this family of proteins has not, as yet, been determined. However, members are thought to be encoded for by spermatogonially-expressed, germ-cell-specific genes [1]. This family of proteins is found in eukaryotes. Proteins in this family are typically between 177 and 384 amino acids in length. There are two conserved sequence motifs: FIN and LAL.

1: Molecular and cytogenetic characterization of two azoospermic patients with X-autosome translocation. Lee S, Lee SH, Chung TG, Kim HJ, Yoon TK, Kwak IP, Park SH, Cha WT, Cho SW, Cha KY; J Assist Reprod Genet. 2003;20:385-389. PMID:14531651