9q21

9q21 is a cytogenetic band on the long arm of human chromosome 9. In human cytogenetics, the long arm is designated q and divisions into bands such as 9q21 are used to describe the physical location of genes and chromosomal features. The 9q21 region lies on the distal part of the chromosome’s long arm and is subdivided into subbands such as 9q21.1 to 9q21.3.

Genomic context: Like other cytogenetic bands, 9q21 contains multiple genes and regulatory elements. The exact assortment of genes present in this interval depends on the genome assembly being used, but the region is generally described as housing several protein-coding and non-coding elements. The band serves as a reference point for locating loci of interest in genetics research and for reporting chromosomal rearrangements in clinical cytogenetics.

Clinical relevance: Abnormalities involving the 9q21 interval, including copy number variations or chromosomal rearrangements, have been reported in a range of conditions. The clinical significance of any alteration in this region depends on the specific genes and regulatory elements affected as well as the size and nature of the genomic change. In clinical reports, 9q21 is often referenced as part of a broader description of chromosomal abnormalities rather than as a single syndrome or disease locus.

See also:

- Chromosome 9

- Cytogenetic banding

- Genome reference assemblies