Human Cytogenetics

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Human Cytogenetics

	Human Cytogenetics For many years before 1956 the chromosome number in man was recorded as 48. In 1956, two cytologists, J. H.Tjio and A. Levan working in Sweden, investigated 46 chromosome number in the tissue culture preparations of lung tissue representing four different human embryos.
Their discovery was later on supported by the investigations of several human cytologists such as C. E. Ford and J. L. Hammerton (1956) ; S. Makino and M. S. Sasaki (1961), etc. presently, 46 chromosome has become well established as the 2n number of man.

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