H2AFB1

H2AFB1 is a gene that encodes a member of the H2A histone family, subtype B1. Histones are basic nuclear proteins that are responsible for the nucleosome structure of the chromosomal fiber in eukaryotes. Nucleosomes consist of approximately 146 base pairs of DNA wrapped around a histone octamer composed of pairs of each of the four core histones (H2A, H2B, H3, and H4). The chromatin fiber is further compacted through the interaction of a linker histone, H1, with the DNA between the nucleosomes to form higher order chromatin structures. This gene is part of a region that is repeated three times on chromosome X, once in intron 22 of the F8 gene and twice closer to the Xq telomere. This record represents the middle copy.

Function

The H2AFB1 gene is involved in the packaging of DNA into chromatin. Chromatin is a complex of DNA and protein found in the nucleus of cells that condenses to form chromosomes during cell division. The H2AFB1 gene provides instructions for making a protein called histone H2A type B1. Histones are structural proteins that bind to DNA and give it a more compact shape.

Clinical significance

Mutations in the H2AFB1 gene have been associated with certain types of cancer, including breast cancer and ovarian cancer. The exact role of the H2AFB1 gene in these cancers is not yet fully understood, but it is thought to be involved in the regulation of gene expression.

See also

• Histone
• Chromatin
• DNA
• Cancer