united-states
To add specific examples to what Dale M pointed out about the "immutable characteristics […] 'fundamental to human dignity", a report by the Tahirir Justice Center, in what appears to be a recurring issue, published in the same month of this question, entitled "Tahirih Explains: Gender-Based Asylum" discusses multiple BIA decisions, binding on the USCIS and Immigration Courts, and affirmed, that being a woman is a particular social group, and persecution is recognized as such against members thereof; alas, challenged constantly in the center of changing administrative policies.
The following are they:
In 1985, in Matter of Acosta, the U.S. Board of Immigration Appeals (BIA) explained that the “particular social group” ground for asylum protects individuals persecuted on account of a fundamental characteristic, including one’s sex.
"In 1996, in Matter of Kasinga, the BIA granted asylum to a young woman fleeing female genital mutilation/cutting and forced marriage, recognizing that her persecution was partly motivated by her gender. The precedent set by Kasinga seemed to pave the way for those fleeing other types of gender-based violence.
But in 1999, in Matter of R-A-, the BIA denied asylum to Rodi Alvarado, a woman who had escaped severe domestic violence. This new precedent bred uncertainty, and cases involving gender-based persecution were decided inconsistently across the country. Realizing the need for a nationwide clarification that domestic violence victims could be granted asylum protections, then-Attorney General Janet Reno voided the decision in Matter of R-A- and called for federal regulations settling the debate. While the regulations were never issued, a decade of litigation and advocacy finally resulted in the BIA reversing course and granting asylum to Ms. Alvarado in 2009.
Unfortunately, without regulations prescribing a clear path to protection for survivors of domestic violence, immigration judges and other officials continued to issue inconsistent decisions. Many of them remained confused about the state of the law, the dynamics of abuse, and the role of government in condoning, allowing, and even perpetuating domestic violence. As a result, many individuals were wrongly denied protection, incorrectly decided cases went through time and resource intensive appeals, and the legal landscape became increasingly complex and difficult to navigate. Finally, in 2014 the BIA clarified the situation when it ruled in Matter of A-R-C-G- that domestic violence was broadly a form of persecution for which asylum could be granted.
This positive development did not last long, however, as the precedent set by A-R-C-G- was revoked by then-Attorney General Jeff Sessions in 2018’s Matter of A-B-. The decision clearly attempted to undo decades of legal advocacy, but contained profound legal flaws and is being challenged in legal cases around the country."