PRM2 and Abnormal sperm morphology: Tuttelmann and colleagues proposed that 5 SNPs (rs35262993, rs35576928, rs737008, rs1646022 and rs2070923) of PRM1 and PRM2 are associated with mild oligozoospermia (n = 77) or teratozoospermia (n = 88) in a Caucasian population16.