Abstract
Male infertility impacts millions of couples yet, the etiology of primary infertility remains largely unknown. A critical element of successful spermatogenesis is maintenance of genome integrity. Here, we present a genomic study of spermatogenic failure (SPGF). Our initial analysis (n = 176) did not reveal known gene-candidates but identified a potentially significant single-nucleotide variant (SNV) in X-linked germ-cell nuclear antigen (GCNA). Together with a larger follow-up study (n = 2049), 7 likely clinically relevant GCNA variants were identified. GCNA is critical for genome integrity in male meiosis and knockout models exhibit impaired spermatogenesis and infertility. Single-cell RNA-seq and immunohistochemistry confirm human GCNA expression from spermatogonia to elongated spermatids. Five identified SNVs were located in key functional regions, including N-terminal SUMO-interacting motif and C-terminal Spartan-like protease domain. Notably, variant p.Ala115ProfsTer7 results in an early frameshift, while Spartan-like domain missense variants p.Ser659Trp and p.Arg664Cys change conserved residues, likely affecting 3D structure. For variants within GCNA’s intrinsically disordered region, we performed computational modeling for consensus motifs. Two SNVs were predicted to impact the structure of these consensus motifs. All identified variants have an extremely low minor allele frequency in the general population and 6 of 7 were not detected in > 5000 biological fathers. Considering evidence from animal models, germ-cell-specific expression, 3D modeling, and computational predictions for SNVs, we propose that identified GCNA variants disrupt structure and function of the respective protein domains, ultimately arresting germ-cell division. To our knowledge, this is the first study implicating GCNA, a key genome integrity factor, in human male infertility.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1169-1182 |
| Number of pages | 14 |
| Journal | Human Genetics |
| Volume | 140 |
| Issue number | 8 |
| DOIs | |
| State | Published - Aug 2021 |
Funding
This study was supported by The Eunice Kennedy Shriver NICHD Grant HD080755 (ANY), the Magee-Womens Research Institute University of Pittsburgh Start Up Fund (ANY), PA DoH Grant SAP4100085736 (ANY), NIH P50 Specialized Center Grant HD096723 (KO, ANY, DC, PNS, KH, and MBE), German Research Foundation Clinical Research Unit \u2018Male Germ Cells\u2019 grant DFG CRU326 (FT), National Science Centre in Poland, grants no.: 2017/26/D/NZ5/00789 (AM) and 2015/17/B/NZ2/01157; NCN 2020/37/B/NZ5/00549 (MK), Magee-Womens Research Institute University of Pittsburgh, Faculty Fellowship Award and NICHD T32 HD087194 (JH), GM125812 (MB), GM127569 (MB, JLY, and ANY), NIH R00H090289 (MABE), National Health and Medical Research Council Project grant APP1120356 (MKOB, JAV, and DC), UUKi Rutherford Fund Fellowship (BJH), Estonian Research Council, grants IUT34-12 and PRG1021 (ML), and The Netherlands Organization for Scientific Research grant no.: 918-15-667 as well as an Investigator Award in Science from the Wellcome Trust grant no.: 209451 (JAV). Computational analysis was supported in part by the University of Pittsburgh Center for Research Computing through the resources provided. We wish to thank the participants and clinical staff for making this research study possible. We would also like to recognize Dr. Andrea Berman at the University of Pittsburgh, who provided expert assistance with GCNA 3D modeling. Additionally, we would like to acknowledge Magee-Womens Research Institute scientific editor Bruce Campbell for carefully proofreading the article.
ASJC Scopus subject areas
- Genetics
- Genetics(clinical)
