Reference normal karyotype Chromosomes arranged by size, centromere position and banding into groups A–G, with sex chromosomes last.
46,XX 46,XY
A · B Chromosome 1, metacentric Chromosome 1, metacentric 1 Chromosome 2, submetacentric Chromosome 2, submetacentric 2 Chromosome 3, metacentric Chromosome 3, metacentric 3 Chromosome 4, submetacentric Chromosome 4, submetacentric 4 Chromosome 5, submetacentric Chromosome 5, submetacentric 5 C Chromosome 6, submetacentric Chromosome 6, submetacentric 6 Chromosome 7, submetacentric Chromosome 7, submetacentric 7 Chromosome 8, submetacentric Chromosome 8, submetacentric 8 Chromosome 9, submetacentric Chromosome 9, submetacentric 9 Chromosome 10, submetacentric Chromosome 10, submetacentric 10 Chromosome 11, submetacentric Chromosome 11, submetacentric 11 Chromosome 12, submetacentric Chromosome 12, submetacentric 12 D · E Chromosome 13, acrocentric Chromosome 13, acrocentric 13 Chromosome 14, acrocentric Chromosome 14, acrocentric 14 Chromosome 15, acrocentric Chromosome 15, acrocentric 15 Chromosome 16, submetacentric Chromosome 16, submetacentric 16 Chromosome 17, submetacentric Chromosome 17, submetacentric 17 Chromosome 18, submetacentric Chromosome 18, submetacentric 18 F · G · Sex Chromosome 19, metacentric Chromosome 19, metacentric 19 Chromosome 20, metacentric Chromosome 20, metacentric 20 Chromosome 21, acrocentric Chromosome 21, acrocentric 21 Chromosome 22, acrocentric Chromosome 22, acrocentric 22 Chromosome X, submetacentric Chromosome Y, acrocentric X/Y Stain legend Anatomy of a chromosome Chromosome 9, submetacentric 9 p — short arm (petit), above centromerecen — primary constriction; kinetochore attachmentq — long arm, below centromerepter / qter — telomeric ends9qh — variable heterochromatin blockSchematic only — not diagnostic. These illustrations simplify banding and cannot detect or confirm real cytogenetic abnormalities. Use validated metaphase karyotype images (and FISH/microarray where indicated) for clinical interpretation.