Human sperm devoid of germinal angiotensin-converting enzyme is responsible for total fertilization failure and lower fertilization rates by conventional in vitro fertilization.
In conventional in vitro fertilization (IVF), complete failure of fertilization occurs in 5% to 15% of treatments. Although the causes may be unclear, sperm defects appear to be the major contributor. However, a convincing test is not yet available that can predict the risk of fertilization failure. In this study, we found that germinal angiotensin-converting enzyme (gACE) (also called testicular ACE) was undetectable in sperm from patients who had total fertilization failure (TFF) and lower fertilization rates (LFRs) by IVF based on Western blot and indirect immunofluorescence analyses. Additionally, almost all of the patients without gACE on sperm (23 of 25) manifested a TT genotype of the rs4316 single-nucleotide polymorphism of ACE. Overall, our results indicate that the absence of gACE expression is responsible for TFF and LFRs by IVF. The rs4316 polymorphism of ACE might be associated with infertility in those patients. We conclude that sperm lacking gACE may be recognized before commencing IVF and that the patients may be directed instead to consider intracytoplasmic sperm injection.
Department of Reproductive Endocrinology, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
Le-Jun
LJ
Li
Department of Reproductive Endocrinology, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
Feng-Bin
FB
Zhang
Department of Reproductive Endocrinology, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
Shu-Yuan
SY
Liu
Department of Reproductive Endocrinology, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
Yong-Hong
YH
Tian
Department of Reproductive Endocrinology, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
Fang
F
Le
Department of Reproductive Endocrinology, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
Li-Ya
LY
Wang
Department of Reproductive Endocrinology, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
Hang-Ying
HY
Lou
Department of Reproductive Endocrinology, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
Xiang-Rong
XR
Xu
Department of Reproductive Endocrinology, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
He-Feng
HF
Huang
Department of Reproductive Endocrinology, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China Key Laboratory of Reproductive Genetics, National Ministry of Education (Zhejiang University), Women's Reproductive Health Laboratory of Zhejiang Province, Hangzhou, Zhejiang, China jinfan@zju.edu.cn.
Fan
F
Jin
D000328:Adult; D020134:Catalytic Domain / Q000235:genetics; D005260:Female; D005306:Fertilization / Q000502:physiology; D005307:Fertilization in Vitro; D005820:Genetic Testing; D005838:Genotype; D006801:Humans; D007248:Infertility, Male / Q000201:enzymology / Q000235:genetics / Q000628:therapy; D008297:Male; D054315:Oocyte Retrieval; D007703:Peptidyl-Dipeptidase A / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012150:Polymorphism, Restriction Fragment Length; D011401:Promoter Regions, Genetic / Q000235:genetics; D020554:Sperm Injections, Intracytoplasmic; D013094:Spermatozoa / Q000201:enzymology*; D013737:Testis / Q000166:cytology / Q000201:enzymology; D017211:Treatment Failure
D007703:Peptidyl-Dipeptidase A
conventional in vitro fertilization; germinal angiotensin-converting enzyme; lower fertilization rates; sperm; total fertilization failure