ABSTRACT
Cytogenetics is an important field of genetics focusing on the study of chromosome structure and related functions in heredity and evolution. In 1902, W. Sutton and T. Boveri independently developed the chromosome theory of inheritance that identifies chromosomes as the carrier of genetic material. Banding cytogenetics has enabled the characterization of constitutional and somatic numerical and structural chromosomal abnormalities through different stages of human development and enriched the medical knowledge of these abnormalities on spontaneous abortion, developmental delay, intellectual disability, multiple congenital anomalies, infertility, tumorigeneses, and metastasis. Banding techniques for human chromosomes were pursued to identify individual chromosomes by recognizable and reproducible patterns. Studies from genome sequencing further defined the organization of heterochromatin and euchromatin in human chromosomes. Under microscopy, human chromosomes have apparent constrictions.
