PROBLEM TO BE SOLVED: To provide a mammalian artificial chromosome (MAC), which is not only stable in the normal cell division process, but also retained for a long term through meiotic division in a reproductive cell and in an individual of a mammal, and passed to the next generation completely.SOLUTION: Provided are an undifferentiated cell, such as an embryonic stem cell (ES cell), which possesses a linear mammalian artificial chromosome a method for producing a mammal containing the linear mammalian artificial chromosomes in cells in each types of organizations stably for a long term, by using the undifferentiated cell and the mammal thus obtained.
