widespread epigenetic abnormalities suggest a broad dna methylation erasure defect in abnormal human sperm广泛的表观遗传异常建议广泛dna甲基化在人类精子异常消除缺陷.pdf

Widespread Epigenetic Abnormalities Suggest a Broad DNA Methylation Erasure Defect in Abnormal Human Sperm 1. 2. 2 5 1,3 4,5 Sahar Houshdaran , Victoria K. Cortessis *, Kimberly Siegmund , Allen Yang , Peter W. Laird , Rebecca Z. Sokol 1 Department of Biochemistry and Molecular Biology, Keck School of Medicine, University of Southern California, Los Angeles, California, United States of America, 2 Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, United States of America, 3 Department of Surgery, Keck School of Medicine, University of Southern California, Los Angeles, California, United States of America, 4 Department of Obstetrics and Gynecology, Keck School of Medicine, University of Southern California, Los Angeles, California, United States of America, 5 Department of Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, United States of America Background. Male-factor infertility is a common condition, and etiology is unknown for a high proportion of cases. Abnormal epigenetic programming of the germline is proposed as a possible mechanism compromising spermatogenesis of some men currently diagnosed with idiopathic infertility. During germ cell maturation and gametogenesis, cells of the germ line undergo extensive epigenetic reprogramming. This process involves widespread erasure of somatic-like patterns of DNA methylation followed by establishment of sex-specific patterns by de novo DNA methylation. Incomplete reprogramming of the male germ line could, in theory, result in both altered sperm DNA methylation and compromised spermatogenesis. Methodology/ Principal Finding. We determined concentration, motility and morphology of sperm