BANF2 (barrier-to-autointegration factor family member 2) is a testis-predominant protein that may play regulatory roles in chr20 organization and nuclear envelope function. While BANF2 is structurally related to BAF, a DNA-binding protein essential for chr20 organization and nuclear envelope assembly 1, BANF2 appears to have more specialized functions. BANF2 is identified as a spermatid-specific BAF paralog (BAF-L) that localizes at the caudal nuclear envelope during spermatogenesis 2. In this context, BAF-L functions redundantly with nucleoporin NUP210L to maintain nuclear integrity and organize manchette microtubules, with mutations in both genes causing male infertility through impaired sperm head condensation 32. However, BANF2 single knockout in mice does not impair spermatogenesis or fertility, indicating it is not independently essential 4. BANF2 protein levels are reduced in spermatozoa from obese men, a condition associated with impaired male fertility 5. Additionally, genome-wide association studies identify BANF2 locus variants associated with cognitive function in elderly Japanese populations, suggesting potential neurological roles 6. These findings indicate BANF2 has tissue-specific functions, particularly in male germ cells and potentially cognition, operating through redundant pathways.