TBC1D21 and Abnormal sperm morphology: Fig 8A reveals that TBC1D21 was localized at elongated spermatids and mature sperm (arrows). The results from human testicular sections are similar to the murine results from our previous study. [31]. Further, the data from Fig 8B was derived from the cDNA microarray analysis of 20 sperm samples by Platts et al.2007 [38]. Transcript levels of TBC1D21 in sperm were decreased in men with teratozoospermia (n = 13), compared with those in healthy controls (n = 8).