Figure 1 Schematic representation of human chromosome 9 (ideogram). The centromere is the structural region of the chromosome that binds with the nuclear spindle at mitosis and meiosis. The telomere refers to each end region of the chromosome, which consists of tandem repeats of simple DNA sequences. The chromosome is comprised of a short arm (p) and a long arm (q). The dark and light areas reflect the unique banding pattern of chromosome 9 when stained using cytogenetic techniques. The nomenclature of each band is indicated on the right side of the chromosome. A segment corresponding to the telomeric end of the long arm of chromosome 9 (9q32–q34), which encompasses the 155 kb COL27A1, 20 kb tenascin C (TNC), 20 kb ABO and 201 kb COL5A1 genes, is also shown. The vertical lines represent the relative position of each gene, while the arrows indicate the direction of their transcription. COL27A1 encodes type XXVII collagen; TNC encodes TNC; ABO encodes the ABO transferases; and COL5A1 encodes the pro‐α1(V) chain of type V collagen. Mb, megabase.