Molecular Basis of Somoclonal Variation - Somaclonal variation may arise due to any of the following events at molecular level:
(i) changes in chromosome number and/or structure,
(ii) gene mutation,
(iii) plasmagene mutation,
(iv) alteration in gene expression,
(v) gene amplification,
(vi) mitotic crossing over,
(vii) transposable element activation, and
(viii) rearrangements in cytoplasmic genes.