Cj. Farr et al., GENERATION OF A HUMAN X-DERIVED MINICHROMOSOME USING TELOMERE-ASSOCIATED CHROMOSOME FRAGMENTATION, EMBO journal, 14(21), 1995, pp. 5444-5454
A linear mammalian artificial chromosome vector will require at least
three functional elements: a centromere, two telomeres and replication
origins, One route to generate such a vector is by the fragmentation
of an existing chromosome, We have previously described the use of clo
ned telomeric DNA to generate and stably rescue truncated derivatives
of a human X chromosome in a somatic cell hybrid. Further rounds of te
lomere-associated chromosome fragmentation have now been used to engin
eer a human X-derived minichromosome. This minichromosome is estimated
to be <10 Mb in size, In situ hybridization and molecular analysis re
veal that the minichromosome has a linear structure, with two introduc
ed telomere constructs flanking a 2.5 Mb a-satellite array, The highly
truncated chromosome also retains some chromosome-specific DNA, origi
nating from Xp11.21, There is no significant change in the mitotic sta
bility of the minichromosome as compared with the X chromosome from wh
ich it was derived.