Histone variants are specialized histone proteins differing from the canonical histones in their sequence and function and which play specialized roles in chromatin structure and gene regulation. H2A variants include H2A.Z, one of the best-studied histone variants. It replaces canonical H2A in nucleosomes and is involved in transcriptional regulation and chromatin remodelling. H2A.Z-containing nucleosomes have unique structural properties, making them more accessible for gene expression. H2A.Z is therefore found in most inducible promoters and facilitates faster transcriptional induction. MacroH2A variants meanwhile contain an additional macro domain. Unlike H2A.Z they are associated with gene silencing, particularly in heterochromatic regions. MacroH2A can additionally recruit chromatin remodellers and other factors to promote a repressive chromatin state. A final H2A variant, H2A.X, is involved in DNA repair. Upon DNA double-strand breaks, H2A.X can be rapidly phosphorylated, marking the damaged sites and facilitating the recruitment of repair factors. It therefore plays a critical role in maintaining genome stability. Of H2B variants, H2B.W is associated with testis-specific gene regulation, whilst H2B.Z is, like H2A.Z, involved in transcriptional regulation and chromatin dynamics, influencing nucleosome stability and accessibility. For H3 variants, H3.3 is involved in nucleosome turnover and histone replacement during transcription and DNA repair. It is incorporated into chromatin outside of S-phase and is enriched at active genes. CENP-A is a centromere-specific histone H3 variant that replaces H3 at centromeres and is essential for accurate chromosome segregation during cell division. H3t is a testis specific H3 variant found in elongating spermatids and is involved in sperm chromatin compaction. Finally, for H4 variants, H4K20me1 is methylated at lysine 20 and is associated with heterochromatin and gene silencing. Histone variants influence gene expression by modulating chromatin accessibility and nucleosome stability. For example, H2A.Z and H3.3 are often associated with active genes, whilst macroH2A and certain H2A variants are linked to gene repression. These variants can therefore either promote or inhibit the binding of transcription factors and other regulatory proteins, thereby shaping gene expression patterns. Histone variants contribute to chromatin dynamics and remodelling processes. They can affect nucleosome stability, positioning, and turnover, influencing the accessibility of DNA for various cellular processes including transcription, DNA repair, and replication. Histone variants can also contribute to epigenetic inheritance, whereby specific chromatin states are propagated through repeated cell divisions. For example, the presence of CENP-A at centromeres ensures that the centromeric chromatin is faithfully inherited during mitosis, maintaining chromosome integrity. Variants like H2A.X and H3.3 also play roles in DNA repair mechanisms. H2A.X is rapidly phosphorylated at sites of DNA damage, marking these sites as requiring DNA repair. H3.3 is involved in nucleosome replacement during DNA repair processes, promoting genome stability. CENP-A, the centromere-specific histone variant, is essential for correct chromosome segregation during cell division, ensuring that sister chromatids are accurately distributed to daughter cells. Some histone variants, such as H2B.W, H3t, and macroH2A, are specific to germ cells and play roles in chromatin compaction in sperm cells. This compaction is essential for the tight packaging of the paternal genome. We provide a comprehensive product range of research reagents for investigating histone variants, including Histone H2A.X antibodies, Histone H2A.Z antibodies, CENPA antibodies, Histone H3.3 antibodies, and HMGN2 antibodies. Explore our full histone variants product range below and discover more, for less.