Table 1.
The effects of cryopreservation on sperm DNA methylation.
| Gene | Species | Cryopreservation method | DNA methylation assay | Result(s) | Reference |
|---|---|---|---|---|---|
| MEG3, H19, LIT1, SNRPN, MEST, ALU, LINE1, VASA, and MTHFR | Human | Slow freezing | Bisulfite pyrosequencing of genomic DNA | No alteration in DNA methylation status regardless of cryopreservation duration. | Kläver et al. 2012 [8] |
| H19 and MEST imprinting control region (ICR) | Human | Vitrification | Bisulfite sequencing PCR (BSP) method | No significant alteration in DNA methylation status between cryoprotectant, cryopreservation process, or duration of cryopreservation groups. | Lu et al. 2015 [9] |
| Global DNA | Horse | Slow freezing | Increased the DNA methylation level. | Aurich et al. 2016 [47] | |
| SNRPN and GRB10 | Human | Vitrification | Sequenom DNA sequencing | Significant changes on sperm DNA methylation. | Zhou et al. 2017 [48] |
| Global DNA | Colossoma macropomum | Vitrification | Enzymatic DNA methylation analysis | Significant changes on sperm DNA methylation caused by all cryoprotectants and exhibition of more delays and abnormal embryonic development. | De Mello et al. 2017 [49] |
| Global DNA | Goldfish, zebrafish | Slow freezing | Luminometric methylation assay | No alteration in global DNA methylation of goldfish spermatozoa after cryopreservation with methanol, reduced DNA methylation with dimethylsulfoxide and 1, 2-propanediol. | Depincé et al. 2020 [50] |
| Increased DNA methylation of zebrafish spermatozoa after cryopreservation with methanol. | |||||
| Promoters of UBE3A and SNURF-SNRPN, PWS-ICR and AS-ICR | Human | Vitrification | Quantitative methylation specific PCR (qMSP) | No alteration in DNA methylation. | Khosravizadeh et al. 2020 [51] |
| Global DNA | Rabbit | Freeze-drying | Immunohistochemistry | No alteration in global DNA methylation. | Mercati et al. 2020 [52] |
| Global DNA | Rooster | Slow freezing | Immunohistochemistry | No difference in DNA methylation between the Lake and Beltsville extenders. | Salehi et al. 2020 [53] |
| Significant decrease in H3K4 methylation and H3K9 acetylation after cryopreservation with Lake extender. | |||||
| Global DNA | Ram | Slow freezing | Immunohistochemistry | Increase DNA methylation during prolonged exposure to capacitating conditions (1–4 h). | Peris-Frau et al. 2021 [54] |
| Global DNA | Ram | Slow freezing | ELISA | Significant increase in global DNA methylation. | Güngör et al. 2021 [55] |