Editing Infertility (section)

===Unexplained infertility===
{{Main|Unexplained infertility}}
In the US, up to 15% of infertile couples have unexplained infertility, in which no identifiable cause is found.<ref name="Carson 2021" /> [[Polymorphism (biology)|polymorphisms]] in [[folate pathway]] genes may be a cause for fertility complications in some women with unexplained infertility.<ref>{{cite journal | vauthors = Altmäe S, Stavreus-Evers A, Ruiz JR, Laanpere M, Syvänen T, Yngve A, Salumets A, Nilsson TK | display-authors = 6 | title = Variations in folate pathway genes are associated with unexplained female infertility | journal = Fertility and Sterility | volume = 94 | issue = 1 | pages = 130–137 | date = June 2010 | pmid = 19324355 | doi = 10.1016/j.fertnstert.2009.02.025 | doi-access = free }}</ref> Epigenetic modifications in sperm may also be responsible for unexplained infertility.<ref>{{cite journal | vauthors = Aston KI, Uren PJ, Jenkins TG, Horsager A, Cairns BR, Smith AD, Carrell DT | title = Aberrant sperm DNA methylation predicts male fertility status and embryo quality | journal = Fertility and Sterility | volume = 104 | issue = 6 | pages = 1388–1397 | date = December 2015 | pmid = 26361204 | doi = 10.1016/j.fertnstert.2015.08.019 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Dada R, Kumar M, Jesudasan R, Fernández JL, Gosálvez J, Agarwal A | title = Epigenetics and its role in male infertility | journal = Journal of Assisted Reproduction and Genetics | volume = 29 | issue = 3 | pages = 213–223 | date = March 2012 | pmid = 22290605 | pmc = 3288140 | doi = 10.1007/s10815-012-9715-0 }}</ref>