Autophagy is an intracellular bulk degradation system, which delivers cytoplasmic components to the lysosome/vacuole. In yeast and mammalian cells, the Apg12-Apg5 conjugate, together with Apg16, form a multimeric complex, which plays an essential role in autopihageosome formation. By large-scale sequencing analysis of a human fetal brain cDNA library, we isolated a cDNA encoding a putative protein with 607 amino acid residues, which shows 90% identity and 93% similarity to mouse Apg16L. This protein, designated human Apg16L, contains a coiled-coil domain and a motif with seven WD repeats, which are also shared by mouse Apg16L. Database searching revealed that Apg16L is mapped to chromosome 2q37.1 and there exist at least four splice variants.