ABSTRACT Population cytogenetics is the study of the incidence of major and minor chromosomal aberrations in a rather random-sample of a population. The main aim of such type of studies had been to estimate the incidence of various chromosomal anomalies, their causation and the selective forces operating on persons with these anomalies. It is also stressed to study of different populations having contracts with environmental chromosome damaging agents, both mutagenic chemicals and irradiation effects (Court-Brown 1967). Quantitative karyotype term was assigned to the type of study in which observations of chromosomal anomalies and variant among normal healthy individuals were reported (Lubs and Ruddle 1970). Studies on human chromosomes had revealed that there was a great deal of polymorphism with certain pairs of complement. The variation in human chromosome can be divided in two parts: (i) Major and cryptic aberrations which are associated with developmental malformation and reproductive wastages and (ii) Variations which seem not have phenotypic disadvantage. In the present study an attempt has been made to review the incidence of both of them investigated in various human populations.